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Chapter 7



China-Burma-India Theater

John W. H. Rehn. Ph. D.


    The China-Burma-India theater was established on 4 March 1942 to transport supplies to the forces of the Chinese Central Government (map 19).1 To accomplish this mission, it was necessary to augment existing air transport facilities and to build a road from India to the Burma Road leading to China on ground which it hoped to wrest from the Japanese. These major activities had to be carried on more or less simultaneously. In addition, Army Air Forces supported Chinese, British, and American operations. Other elements of the U.S. Army provided advisory, training, liaison, and other facilities to assist the Chinese Central Government.

    The first major event in the theater was the inglorious retreat from Burma in the spring of 1942. For all practical purposes, this divided the theater into two distinct areas separated by the Himalayan uplift. At that time, limited flights over these mountains were being made principally by the Chinese National Aviation Corporation. The India-China Wing of Air Transport Command was directed to construct airfields and to establish regular flights in this area for the movement of military personnel and to China. This dangerous and arduous trip was the only available means of communication with China except for the century-old caravan routes crossing various parts of central Asia which were impractical for movement of essential personnel and materiel. Air service over "the hump" was steadily built up until tonnage moved by this means increased from the initial trickle to sizable quantities.

    Other means were still necessary, however, to move the enormous quantities of gasoline, expendable supplies, vehicles, and other heavy equipment. A supply route was commenced in December 1942 to extend from the Ledo area of Assam, India, across the Patkai Range through the Hukawng and Irrawaddy Valleys to the old Burma Road, subsequently renamed the Stilwell Road. This project involved construction through virgin jungles crossed only by poor foot trails or pack trails and peopled by indigenous tribes. During 1943 and 1944, when construction of the road, pipelines, and telephone lines was continuing as closely behind combat operations as supply and climatic conditions would allow, great quantities of material were moved inland from

1 Except as otherwise indicated, data in this chapter are derived from Van Auken, H. A.: A History of Preventive Medicine in the U.S. Army Forces of the India-Burma Theater, 1942-45. [Official record.]


MAP 19.- Southeast Asia, showing India-Burma theater with major administrative divisions and China theater in 1945


the ports for construction purposes and to build up a backlog of supplies for shipment over the road on its completion. The road was finished and opened for the first China convoy on 1 February 1945 and was officially closed on 31 October 1945.

    Operations for the capture of northern Burma, across which the road was to be built, were carried on by the Chinese Army in India and by Merrill's Marauders. This polyglot organization was assembled in India and started from the Ledo area late in February 1944, conducting a jungle campaign which led to the capture of Myitkyina, Burma, in August 1944.

    The Burma Road in the Salween River area was captured by the Y Force (Chinese). The second American contingent, the Mars Task Force, left Myitkyina in August 1944, to make contact with the Y Force, after which they headed south and made contact with British troops, which had been operating in central and south Burma. This completed the neutralization of the entire route over which the highway extended to K'un-ming, China.

    The pipeline project was really twofold. One branch went to the Manipur Road area of Assam to supply petroleum products to the British and to the Tenth Air Force poised for their south Burma offensive. The other line went through the Brahmaputra Valley supplying airfields, after which it continued with the road and made contact, early in 1945, with the section being constructed from K'un-ming to near the China-Burma border.

    The Tenth Air Force supported all operations, both the Chinese-American in northern Burma and those of the British. The Fourteenth Air Force supported Chinese operations and performed missions in conjunction with the various Pacific commands to the limit of their resources. Finally, the Twentieth Air Force was established in the theater for long-range bombing of enemy strongholds.

    Many Americans were involved in advisory capacities or in training and supplying the Chinese, both in China and in India. Additional personnel served to maintain liaison with the various Chinese forces. The India-Burma theater, except the area from Ledo eastward in Assam through northern Burma and, for a time, a limited portion of eastern Assam (Manipur Road and Kohîma area), was considered a rear area. In the China theater, established on 24 October 1944, supply and training functions were intimately connected with various Chinese operations.

    Bases were established at ports and at intervals along water, rail, and road transportation systems, either utilized in part or operated by Americans. The actual location and disposition of forces depended upon operating conditions, transshipment points, maintenance needs, and other problems. Army Air Force installations, particularly Air Transport Command bases, formed a network linking the various parts of the theater. Installations were especially numerous through the upper Assam portion of the Brahmaputra Valley. With the exception of bases in eastern Bengal and Assam, Tenth Air Force installations were located near those of other commands. In China, Army Air


Force installations were principally combat bases. The Fourteenth Air Force worked in conjunction with the Chinese ground troops. In the Bengal area, relatively isolated bases were installed for the Twentieth Air Force and for some sections of the Tenth Air Force.

    With the cessation of hostilities, all bases contracted in size and gradually closed as evacuation progressed. In China, bases were established at some of the major ports to facilitate the movement of personnel and supplies in the freed areas. At the end of 1945, only a few of the main depot areas, particularly those near ports or centrally located for a large area, were left in operation.



    The occupied portion of the theaters included areas of India, Burma, and China with a few personnel stationed in Ceylon:3 The India-Burma area was enormous, being more than 2,400 miles from east to west and 1,800 miles from north to south, including more than 2 million square miles (map 19). In southern China, troops were scattered in portions of six provinces which had an area of about three-quarters of a million square miles.

    As a whole, the India-Burma area is one of great diversity in physiographical, climatological, and biological conditions. Within its borders are areas of great elevation and large river plains practically at sea level. It also encompasses regions with very great rainfall as well as those with true deserts. In all the area, with but limited exceptions, malaria was either an actual or a potential problem. Roughly, India may be divided by landform and geology into three sections (map 20) : The northern mountains or Himalayan uplift; the dissected plateau in the peninsular portion of India, at times spoken of as the Deccan; and the great Indian Plains, often called the Plains of Hindustan. This latter includes the valleys of the Indus. Ganges, and Brahmaputra Rivers. On the east, the Assam Hills are actually contiguous with the Burma mountains. These together form an effective barrier between India and Burma. Burma has, in addition, the following distinct geographic areas: Irrawaddy Valley, Shan Plateau, and Tenasserim Coast.

    The hill rest camps, such as Darjeeling, India, were located on the south slope of the Himalayas. Usually, they were in the deciduous forest belt at 6,000 to 9,000 feet elevation. These areas were mostly natural forest with some tea gardens. In most of the area, malaria is not a major problem.

    Bombay, a port utilized at times by U.S. Forces, is on the west coast. It is situated on a hilly island, sheltered at all seasons.

    Bangalore, in the Mysore State, was an important Army Air Force installation. Its elevation gave it a healthy, pleasant aspect.

2 (1) Cressy. George B.: Asia's Lands and Peoples; A Geography of One-Third the Earth and Two-Thirds Its People. New York: McGraw-Hill Book Co., Inc., 1944. (2) China Handbook, 1937-43, New York: The Macmillan Co., 1943.
3 It will be recalled that the partition of Pakistan from India did not take place until 1947. Prepartition names are retained in this chapter.


MAP 20.- Southeast Asia showing geographic divisions in portions of India and Burma occupied by U.S. troops.

    Ceylon served as a base for a limited number of U.S. troops. They were mainly stationed in the interior hills which have the remnants of forests but are largely devoted to tea gardens. It may be described as a "typical" tropical island. At times, the area has explosive malaria epidemics.

    The great Hindustan Plain is the section in which most of the rear area installations and Air Force bases were established. The forward areas passed through the mountain barrier separating these plains from the essentially similar river plains of Burma.

    The great Indian Plain itself is divisible into several major geographic regions (map 20) The Bengal-Orissa lowlands, Ganges Valley, Brahmaputra Valley, Indus Valley, and Thar Desert. In all these areas, malaria was prevalent. The Assam Hills and Burma mountains on the east separate these areas from the Irrawaddy Valley. In all these divisions, except the Thar


Desert and the Indus Valley, troop concentrations were of sufficient size to warrant consideration in some detail. Moving from west to east, one progressed from an area with limited concentrations of forces to the areas in which they were numerous.

    Only at Karachi were troop concentrations permanently established in extreme western India. Karachi, while technically in the Indus Valley, possesses the features of the Thar Desert. It is in a low, level area with little rainfall, mostly a desolate region of shifting sands and scattered xerophytic brush.

    In the Ganges Valley, fairly numerous well-isolated rear installations and airbases were established. This broad valley, with its vast deltaic area and practically featureless relief, is intensely agricultural. It has greater precipitation in the eastern portion.

    The Bengal-Orissa lowlands likewise contained rear area installations and airbases as well as the main port for supplies (Calcutta) for the theater. It is essentially a flood plain area of two river systems, with a deltaic maritime district bordering the Bay of Bengal. It is an agricultural province with relatively heavy rainfall and with trying climatic conditions, ill-suited for Europeans.

    The Brahmaputra Valley is best defined as the region from the rivers entrance into the Assam lowlands to the Bengal-Assam boundary. The valley, which is moist to wet, has considerable agriculture but still retains large tropical forests. Through this area passed the supply lines for and the start of the Stilwell Road and in it were situated many airbases.

    The Assam Hills-Burma mountains barrier was an area in which some combat occurred and through which the road was constructed. This area, with its rugged terrain covered almost entirely with dense tropical rain forests, was a little known section of the world.

    The Irrawaddy Valley, the northern portion of which concerned us, is another set of river systems with flood plains but with definite elevational relief. In some portions, agriculture is important, but much of the area is either tropical forest or scrub, or has reverted to grassland. Rainfall is heavy in most of the area where Americans were stationed.

    China exhibits great diversity in physiographical, climatological, and biological conditions. However, the south China area in which U.S. troops were stationed exhibited rather limited diversification. This area is composed of the following general regions: Szechwan lowlands, mainly in that province; southern uplands, including parts of Hu-nan, Kuei-chou, Yünnan, and Kuang-hsi Provinces; and southwestern uplands, including portions of Kuei-chou and Yünnan. U.S. troops were scattered through all these areas in order to perform their mission of supply and liaison with Chinese forces.

    The Ssu-ch'uan lowland is an isolated area near the heart of China. Elevations from 3,000 to 4,000 feet are found with valleys of one-half this height. Ch'ung-ch'ing dominates this area. There is also an alluvial fan, the Ch'eng-tu Plain, near its western margin. The natural flora has largely been


replaced by cultivated crops. Pine, bamboo, and cypress are characteristic of the area, with deciduous trees mixed with pine on the higher hills.

    The southern uplands include a large area of south China. Hills and mountains are always in sight. It is estimated that flatland occupies not over 15 percent of the area. Most of the area is under cultivation or is grassland, but remnants of the original tropical semideciduous (broadleaf) and subtropical forests persist.

    The southwestern uplands are a subdued continuation of the Tibetan highlands. The only level area is the K'un-ming Plain. As a whole, it is a region of plateau remnants cut by deep valleys. Undisturbed areas are rare, but in places the original flora, consisting of subtropical forest and dense coniferous and deciduous upland forests, may be found.


    Within India and Burma, all climatic conditions present an appreciable variation. In general, from west to east there is a progression from a very arid region through increasingly moist areas to the rainsoaked tropical forests of the Assam Hills. In the Irrawaddy Valley, conditions are similar to those of the Bengal-Orissa lowlands and the Brahmaputra Valley. Throughout much of the area, the conventional seasons--spring, summer, autumn, and winter--do not occur. The area as a whole has three seasons: The wet (monsoon), the cool, and the hot. Most of the precipitation occurs during the monsoon season. The time of arrival of the wet southwest monsoon depends largely on the latitude of the location. In late May or early June, it begins in Ceylon, south India, and the southern tip of Burma, reaching Bombay early in June and Calcutta by the middle of that month, then progressing up the Ganges and Brahmaputra Valleys. These conditions continue until mid-September in Punjab, mid-October in Bombay and in the Irrawaddy Valley, late October in Calcutta, and early November in the south. In the winter, rain is brought to Ceylon by the northeast monsoon.

    It is during the summer that the greatest precipitation occurs in China. The southern area of China, with 40 to 75 inches of rain, is more moist than the northern area, which usually has less than 25 inches. The southern region shows much less diversification than is found in India and Burma.

    Table 47 presents the average precipitation and seasonal variation in selected localities in the various areas.

    In India and Burma, the wet (monsoon) season is one in which the temperature is fairly high and the humidity high. As the season progresses, the humidity becomes higher and the actual temperature lower, although the perceptible temperature increases. After the rains, the temperature decreases and the cool season has arrived. This continues until late in February. Early in March, the hot season begins with its high daytime temperatures but relatively cool nights. This condition prevails until the monsoon breaks.

    Temperature conditions at selected localities in various areas are shown in table 48.


TABLE 47.- Average precipitation (in inches) at selected localities in China, Burma, and India, for various time periods 1


TABLE 48.- Average temperatures in degrees Fahrenheit, in selected localities, in China, Burma, and India 1



    As is well known, the racial types, religion, languages, and cultures found in India and Burma are diverse.4 Many races other than the true Chinese are found in China. In the southwest, especially, where most U.S. troops were stationed, there were many residents of other racial stocks. Much of the area is overpopulated, and troops were almost constantly in close association with the local inhabitants in all but a few areas. This was partly because the residents were living in proximity to the various supply lines and also because large numbers of labor troops and civilians were employed in various phases of the work. In China, the mission of liaison or supply involved continual contact with the residents and with the Chinese Armed Forces. The only areas in which these conditions did not prevail were along portions of the Stilwell Road, sections of the pipeline, and in areas in north Burma. Here for various reasons, such as general inaccessibility, limited tribal population, or evacuation due to combat activities, contact with the local population was more limited.

    On the whole, throughout the area, local housing was poor, sanitation practically nonexistent, and public health work limited. Tn some portions of India, control measures had been established to reduce the malaria incidence, but such activities were limited by lack of sufficient funds.

    Malaria is the most important disease in both India (map 21) and Burma (map 22).5 In India, with a population of about 388 million in 1941, it has been estimated that there were between 100 and 200 million cases of malaria and between 1 and 1½ million deaths each year from this disease. 6 In Burma with a population of 16,823,798 in 1941, there were over one-half of a million (604,049) hospitalizations during the year 1939, with a death rate of 214 per 100,000 population in the towns alone.7 Although malaria is known to be a major problem in south China, statistics concerning its frequency are not available. In some instances, U.S. troops were stationed in areas of hyperendemicity, while large numbers were in areas of moderate to high endemicity.


    The anopheline fauna of the India-Burma areas are very diverse, there being more than 50 known forms.8 Over one-half of the species have at some

4 (1) Gilbert William H., Jr.: Peoples of India. Smithsonian Institution War Background Studies, No. 18, April 1944, pp. 17-19. (2) Deigman, H. G.: Burma-Gateway to China: Smithsonian Institution War Background Studies, No. 17, October 1943, pp. 7-9.
5 Of the localities indicated by number on map 22, a selected number are presented and identified in table 50.
6 War Department Technical Bulletin (TB MED) 174, July 1945.
7 War Department Technical Bulletin (TB MED) 77, 2 Aug. 1944.
8 The information in this section dealing with anopheline habits and their roles as vectors of malaria has been compiled from the literature listed below. The evaluation of evidence presented there has taken into consideration knowledge gained by the author while a member of the 35th Malaria Survey Detachment or as Base Section Malariologist. as well as information gained from personal contacts with or correspondence from many of these authors, U.S. Army malaria control personnel in these theaters, and from civil and allied military control personnel within the areas. (1) Christophers, Sir Richard: Diptera, Family Culicidae, Tribe Anophelini (Fauna of British India Including Ceylon and Burma). London: Taylor and Francis, October 1933. (2) Covell, G. : Notes on the Distribution, Breeding Places, Adult Habits and Relations to Malaria of the Anopheline


MAP 21.- Malaria in India

time or place been found infected with malaria oocysts or sporozoites, but only some 11 or 12 species are believed to be important vectors (tables 49, 50, and 51).

Mosquitoes of India and the Far East. J. Malaria Institute of India 5: 399-434, December 1944. (3) Russell, Paul P., Rozeboom, Lloyd E., and Stone, Alan: Keys to the Anopheline Mosquitoes of the world, With Notes on Their Identification, Biology, and Relation to Malaria. Philadelphia:  American Entomological society, Academy of Natural Sciences, 1943. (4) Roy, D. N.: The Potential Danger of  Anopheles leucosphyrus in Assam. Indian M. Gaz. 77: 318, May 1942. (5) Notes on the More Important Malaria Vectors of South China, Naval Medical School, National Naval Medical Center, Bethesda, Md., 1945. (6) Clark, R. H. P., and Chowdhury, M. A.: Observations on Anopheles leucosphyrus in the Digboi Area, Upper Assam. J. Malaria Institute of India 4: 103-107, June 1941. (7) Ramsey, G. C., Chandra, S. N., and Lamprell, B. A.: A Record of an Investigation to Determine the Androphilic Indices of Certain Anopheline Mosquitoes Collected on the Tea Estates in Assam and Northern Bengal. Records of the Malaria Survey of India 6: 49-52, March 1936. (8) Knowles, Robert, and Senior-White, Ronald A.: Malaria: Its Investigation and Control, with Special Reference to Indian Conditions. Calcutta: Thacker, Spink and Co., 1927. (9) Quarterly Report, Consultant Malariologist, Allied Land Force, South East Asia Command, January-March 1945. (10) Puri, I. M.: Synoptic Table for the Identification of the Anopheline Mosquitoes of India. 3d edition. Health Bulletin, No. 10, Malaria Bureau No. 2. India: Delhi, Manager of Publications, 1945. (11) Memorandum, Surgeon, Headquarters, U.S. Forces, India-Burma Theater, to The Surgeon General, U.S. Army, 5 May 1945, subject: Publication of an Article on Malaria, enclosure No. 2, Observations on Anopheles leucosphyrus Don, by Capt. Louis C. Kuitert, SnC, and Staff Sgt. John D. Hitchcock.


MAP 22.- Malaria in Burma


TABLE 49.- Distribution of some of the important anopheline vectors of malaria in selected portions of India

TABLE 50.- Distribution of important anopheline vectors of malaria in selected portions of Burma


TABLE 51.- Distribution of important anopheline vectors of malaria in selected provinces of south China


Species Characteristics

    The characteristics of the species of Anopheles which were most important to the U.S. troops in the China-Burma-India theater are described in the paragraphs to follow.

    Anopheles culicifacies Giles 1901 is a widespread species that has been found breeding in a variety of situations. Usually it is found in fresh, clean water but occasionally in brackish water and often in irrigation channels, pools, overflow water collects, slow-moving streams, and quite frequently in wells.

    The culexlike adults are small to medium sized. They feed on both human and cattle blood indiscriminately. The anthropophilic index has been found to vary from 0.3 to 80 percent (the latter, exceptionally high for this species, is believed due to a relative absence of cattle). This mosquito is often found in houses or cowsheds in the daytime on the walls or secreting itself in holes; that is, among dung cakes and chaff. Effective flight is normally about one-half of a mile but may extend to a mile under favorable climatic conditions.

    This species is the most important vector in the plains of India, is the only vector in Ceylon, and has been found to be of importance in Yünnan. It is particularly notorious in regional malaria epidemics. It usually has a low infection rate. In epidemics, however, it has been found to have sporozoite rates and total infection rates as high as 11.7 and 24.5 percent, respectively.

    Anopheles fluviatilis James 1902 is a widely distributed species in India and Burma. It often breeds in foothill stream edges, stream pools, swamps, irrigation channels, and edges of swamps and lakes. Although it prefers sunlit breeding places, it is sometimes found in partial shade. Breeding is often in the immediate vicinity of human habitations.

    Biologically, this species may comprise two races. In south India, A. fluviatilis is strongly anthropophilic, with indices as high as 97 percent. On the other hand, surveys in northern India show indices of 1.4 to 4.6 percent. This strong flier is commonly found resting in houses and at times in cowsheds.

    The southern form is an important vector, with total infective rates of 11 to 26.3 percent. The more northern form has been found naturally infected, but it seems to be of little, if any, importance as a vector.

    Anopheles sinensis Wiedemann 1828 is the commonest Anopheles in China. It has been found to breed in almost any collection of ground water and occasionally even in artificial containers. It has been found in ponds, ricefields, marshes, ditches, slowly flowing streams, borrow pits, and drains. It seems to favor open water, although this is by no means a rule. Usually, the breeding habitats contain aquatic vegetation. It is predominantly a clean water breeder, although in Burma it has been recorded from foul water.

    The observations on biting habits, food preferences, daytime resting places, and other aspects of behavior of this subspecies vary considerably. Whether these variations are due to ecology or to physiological races within the subspecies is not known. In some areas, this species appears to be strongly zoo-


philic, rarely attacking man; in other areas, relatively large percentages of engorged females are found to contain human blood. Of those caught in houses, practically all have human blood, while most of those taken in cowsheds have cattle blood.

    Its role in malaria transmission varies in different parts of its range. It is considered to be the chief vector in the plains of China. Wherever it occurs in appreciable numbers and has anthropophilic feeding habits, it is a potential vector.

    Anopheles jeyporiensis candidiensis Koidzumi 1924 has a widespread distribution and is an important vector in some portions of its range. The typical form, Anopheles jeyporiensis jeyporiensis James 1902 has rarely been found naturally infected and is not considered important in the transmission of malaria. A. jeyporiensis candidiensis is most frequently seen breeding in grassy shallow waters, such as seepages, water from hillsides, abandoned rice-fields, and among the stubble of ricefields. It often occurs in connection with rice cultivation.

    The adult is markedly anthropophilic, although less so than A. minimus. It also attacks domestic animals. Its flight range has been recorded as exceeding one-half of a mile. Usually, it rests in houses or cattle sheds, but in Burma it is reported to leave after feeding. It has been observed biting fiercely toward evening in the open, but usually seeks its host inside habitations or closed shelters.

    A. jeyporiensis candidiensis has been found naturally infected in several areas. It is a vector secondary to A. minimus in the foothills but has had natural infection indices as high as 10 percent during epidemic periods in China. In the Burma highway area, an infection rate of 5.55 percent was found in 1941. It should be regarded as an important vector.

    Anopheles leucosphyrus leucosphyrus Dönitz 1901 is a wild species usually breeding in deep jungle and forest. Larvae have been found in heavily shaded portions of rock pools, in stagnant pools in the beds of mountain streams, in densely shaded swamps, and in borrow pits along heavy forest roads. At times, it has been found some distance from jungle.

    This wild species apparently feeds on humans most commonly during the middle of the night. Its flight range is probably not over 800 meters. It has most often been found resting in such natural situations as tree trunks and overhanging banks. However, in some areas it has been found in houses or trapped in bed nets. In Assam, up to 75 percent were found to have taken human blood.

    Until recently, this species was believed to be a vector only in Indonesia, but it is now known to be of importance also in some areas of Assam, with infection rates of 3.1 to 4.9 percent where A. minimus is less plentiful. It is


probably the chief vector in at least some areas of northern Burma; for instance, a sporozoite rate of 2.7 percent was found at Shingbwiyang, Burma.

    Anopheles maculatus maculatus Theobald 1901 is essentially a stream and riverbed breeder, with a preference for springs and seepages. It is also found in small pools, ricefields, lake margins, and ditches but seems to prefer partially shaded areas with sandy or rocky bottoms.

    The adults enter houses and bite man readily at night, chiefly between 2100 and 0200 hours. The majority leave after feeding and rest outdoors, especially along streambanks. In some areas, the species appears to be more zoophilic than in others, but it is often found to have a high anthropophilic index. An effective flight range of more than one-half of a mile has been found as a result of recent observations.

    Although but few naturally infected individuals have been found in the area of the theaters, it has been considered on epidemiological grounds to be a vector. In the area of the Burma highway, it is probably a secondary vector to A. minimus.

    Anopheles minimus minimus Theobald 1901 is found in eastern and northern India, in Burma, and in southern China. It is a most important vector in Assam and north Burma and is believed to be the most important vector in south China. It breeds in clear, unpolluted slow-running streams and springs with grassy margins and in irrigation ditches and ricefields at low to moderate altitudes. It never breeds in dense virgin jungle, but frequently in secondary jungles.

    The chief resting place is on the walls inside dark houses, the majority being in the lower one-half of the room. About 90 percent of the blood feeding takes place after midnight. It is a highly anthropophilic form often with an index of 85 percent or more. Even those found in the open or in cattle sheds may have an appreciable percent of human blood. It is interesting to note that in Hu-nan, south China, A. minimus apparently leaves habitations after feeding.

    A. minimus is one of the most dangerous malaria carriers because of its domestic habits and its preference for human blood. Large numbers of dissections have shown total infection rates varying from 3 to 18.6 percent. This species is an important vector of malaria wherever found.

    Anopheles pattoni Christophers 1926 is found in China, mainly north of 300 north latitude. As a result, few U.S. troops came in contact with it. Breeding occurs chiefly in slowly running hill streams, in rainwater pools, and in riverbeds with sandy bottoms, usually where considerable algal growth is present. The larvae have been found under the ice, and the species is assumed to be able to pass the winter in this stage.

    The adults are apparently zoophilic as well as anthropophilic. It is considered to be an important vector on epidemiological grounds wherever it occurs.


    Anopheles philippinensis Ludlow 1902 is a widespread species and is an important vector in the Bengal area. It has been found breeding in tanks, pools, drains, ditches, swamps, borrow pits, and ricefields. It breeds only in clear water and has a definitely limited ecological association, some types of aquatic vegetation being preferred while others appear to be inhibitory.

    The adult has a definite preference for resting in human habitations, usually near the floor. Preferred feeding times seem to be from 2000 to 2200 and from 0200 to 0400 hours. Although anthropophilic in Bengal, it seems to be definitely zoophilic in Assam.

    Total infection rates of 1.04 to 7.2 percent have been found in Bengal where it is the most important vector. In Assam and Burma, it is not generally regarded as a vector of importance (fig. 45).

    Anopheles stephensi stephensi Liston 1901 typically breeds in wells, cisterns, flowerpots, discarded tins, roof gutters, and other temporary water receptacles. It also has been found in such places as pools, rivers, streambeds, sluggish creeks, and drains. It can tolerate high salinity and organic pollution. Sunlit breeding places appear preferred. The larvae often sink to the bottom of their breeding location, remaining there for some time so that they may be difficult to discover.

    A. stephensi has a range of dispersal up to 2.5 km., perhaps longer. It readily feeds on man. Adults occur in cowsheds, barracks, and houses but are secretive and difficult to find.

    This species is an important vector under rural conditions in western and northwestern India and under urban conditions in peninsular and northern India.

    Anopheles sundaicus Rodenwaldt 1926 is a broadly ranging species that breeds in saline water. The larvae occur most frequently in sea water lagoons, swamps, and collections of brackish water behind coastal embankments. The water in which it is found usually has a saline content of 1.2 to 1.8 percent but occasionally up to 4 percent and, in the Ganges Delta area, often with as little as 0.4 percent. It usually breeds in the presence of algae.

    Adults are strong fliers and may travel up to 3 miles. They occur in large numbers in cowsheds and in huts and other human dwellings. Females generally prefer human blood and have anthropophilic indices as high as 94 percent. They are voracious, occasionally feeding in daytime but usually during the first half of the night.

    Anopheles sundaicus is highly susceptible to infection, with total infectivity rates up to 23.4 percent. While it is usually an important carrier, it has been found in large numbers where the incidence of malaria was low.

Effect of Military Activity on Mosquito Breeding

    It is possible that in the rear areas mosquito breeding may have been slightly enhanced because additional breeding places were formed as a result


FIGURE 45.- Tank with aquatic vegetation, vicinity of Calcutta, Bengal, showing Anopheles philippinensis breeding area in proximity of campsite.

of construction. It is doubtful, however, whether these breeding sites caused any actual increase in the mosquito population. In practically all areas, the establishment of some type of control around camps reduced the breeding sites. Moreover, these new breeding situations were eliminated as soon as they were noticed.

    In the combat areas, very little is known as to whether or not mosquito production was increased because of military activities. Throughout these areas, malaria control had not previously been attempted, and no information regarding breeding or prevalence of the disease was available.


    Indigenous labor was used throughout the theaters. In many sections, these laborers were brought from other districts. In practically all instances, however, these personnel had previously been exposed to malaria. How much this added to the problem cannot be ascertained. It is known that some of these groups suffered severely from malaria. Routine examinations of thick- and thin-blood films showed about 20 percent positive. Gametocyte rates, however, were always very low.

    Prisoners of war were few, and their care and disposition was in the hands of the British authorities. Information concerning them is given later.


    The annual rates for malaria and for fever of undetermined origin are shown in table 52, by month; the malaria rates are depicted in chart 13. The amount of the fever of undetermined origin which was actually malaria cannot be ascertained. It can readily be seen that malaria was a major problem to troops within the area. Transmission did not, however, continue throughout the year in all portions of the theaters. In examining these figures, it should be noted that suppressive treatment was started in the area forward of

TABLE 52.- Attack rates for malaria and for fever of undetermined origin, China-Burma-India theater, 1942-45


Chart 13.- Attack rates for malaria, China-Burma-India theater, 1942-45

Shingbwiyang, in April 1944, and was extended to include all forces east of the Brahmaputra River by February 1945. In April 1945, Atabrine suppressive therapy was initiated in a large portion of the China theater (chart 14).9 These were regions of high endemicity (maps 21 and 22). In certain organizations, Atabrine suppressive treatment was discontinued late in 1945.

    The malaria rates in the various sections of the India-Burma theater and in the China theater varied considerably, as can be seen in tables 53, 54, 55, and 56 and in charts 15, 16, and 17.

    Malaria rates for most of 1943 among troops stationed along the Stilwell Road are shown in table 57.10 Given for comparison are the predicted rates supplied by British authorities. From table 57, it can be seen that even with the limitations of the malaria control program at that period its efficiency probably materially reduced transmission.

9 Circular No. 13. Chinese Combat Command Provisional, U.S. Forces, China Theater, 4 Apr. 1945.
10 Letter, Lt. Col. Hardy A. Kemp, MC, Rear Echelon, Headquarters, U.S. Army Forces, China- Burma-India, 11 Dec. 1943, subject: Comparative Malaria Rates on the Ledo Road Project.


CHART 14.- Attack rates for malaria, China theater, 1944-45

TABLE 53.- Attack rates for malaria and for fever of undetermined origin, India-Burma theater and China theater, 1944-45


    Owing to the changing of names and of geographic limits of the various sections, the following terms for the areas are defined (map 19) The Base Section included all of India in which there were troops, except Assam. The Intermediate Section comprised all of Assam except the portion from the

CHART 15 .- Attack rates for malaria, Base Section, India-Burma theater, 1944-45

TABLE 54.- Attack rates for malaria, Base Section, India-Burma theater, 1944-45


Margherita-Ledo area eastward to the Burma border. The Advance Section comprised the Margherita-Ledo area of Assam east to the Burma border and all of Burma that U.S. or Chinese troops occupied. Included in this is the territory of the Northern Combat Area Command. The term "China theater"

CHART 16.- Attack rates for malaria, Intermediate Section, India-Burma theater, 1944-45

TABLE 55.- Attack rates for malaria, Intermediate Section, India-Burma theater, 1944-45


has been used for all the area of that country in which there were U.S. troops.

    Because of the scattered distribution of all Army Air Force troops, information about these forces is not given separately. Their malaria incidence is included in that of the area in which they were stationed.

CHART 17.-   Attack rates for malaria, Advance Section, India-Burma theater, 1943-45

TABLE 56.- Attack rates for malaria, Advance Section, India-Burma theater, 1943-45


TABLE 57.- Attack rates for malaria along the Stilwell Road, 1943

    It must be realized that malaria data have numerous sources of error. The amount of malaria that was undiagnosed, fever of undetermined origin, as well as the movement of Army Air Force personnel actually contracting the disease in one area but being hospitalized in another, seems to have been about equal in the different divisions of the theater. However, the number of cases for which records were not turned in (treated in quarters) and the amount of clinical malaria reported was probably greater in the Advance Section than in other areas. Until the middle of 1945, the Advance Section and China theater hospitalized more malaria patients who had contracted the disease outside the limits of their areas than did the others.11 After that time, the Base Section figures show the same disproportionate share of malaria. This condition was brought about by troop movements. Moreover, the administration of Atabrine suppressive treatment to combat forces in June 1944 and to those forward of Shingbwiyang further confused the figures in the Advance Section. After February 1945, all troops in the Advance Section, the Intermediate Section, and a portion of the Base Section were receiving Atabrine suppressive treatment. Similarly, figures from the China theater are confused by the fact that first some of the combat forces and later troops in various portions of the theater were placed on suppressive treatment.

Epidemic Malaria

    The only special epidemic in the China-Burma-India theater occurred in the Karachi area, Sind Province, India, in the fall of 1944 (table 58).12 In this area, as in most others within the theater, the close proximity of a highly

11 Letter, Surgeon, Headquarters, Tenth Air Force, U.S. Army, to Theater Malariologist, Office of the Surgeon, Rear Echelon, Headquarters, U.S. Army Forces, China-Burma-India, 27 Nov. 1943, subject: Malaria Control.
12 Essential Technical Data, U.S. Army Forces, India-Burma theater, for 15 Oct.-15 Nov. 1944, dated 27 Dec. 1944.


infected human reservoir of parasites and of efficient vectors represents the potentiality for an epidemic.

    The Sind Province is usually comparatively dry from July to September, even though this is the so-called wet season. But during 1944, heavy rains occurred in July and August, creating numerous mosquito breeding areas. Weather conditions were near the optimum for breeding and transmission. The mean minimum temperature was 800 F., or above, in the period June through August; practically 800 F., in September; and then it dropped to 73.70 F., in October. These factors produced an explosive epidemic staffing early in September. The spread of the disease was undoubtedly aided by the fact that the previously low rate for malaria in this area had produced a false sense of security. As a consequence, there was a general lapse of malaria precautions and failure to take seriously the warnings issued concerning the possibilities of a malaria outbreak. Soon after control was started in the area, satisfactory results were achieved (table 58). The effect of rapid institution of malaria control under such circumstances cannot be overemphasized.

TABLE 58.- Epidemic malaria in Karachi, India, July through December 1944

Sources of Difficulty

    In all portions of the theaters where there were troops, malaria was present, often highly endemic, and in certain areas hyperendemic (maps 21 and 22). With this situation and with the impossibility of separating troops from the local population, only the application of all feasible means of malaria control could keep the rates from being excessive. Unfortunately, at the start of operations, both antimalaria supplies and personnel were insufficient to establish control.

    At first such supplies as were available to the British were shared with the U.S. forces, and, in addition, permission was given to procure mosquito netting and other supplies locally, even though all supplies were short. Thousands of laborers were made available for drainage projects and for the construction of mosquitoproof quarters. Many troops did not have sufficient instruction


in malaria prevention, and malaria discipline was lax. Intimate contact with the highly infected reservoir population while working in uncontrolled areas, where most personal protective measures were all but impossible, helped to increase infection. Education was stressed, and malaria discipline improved as soon as the importance of the problem was recognized. When U.S. Public Health Service personnel became available, all the antimalaria work was greatly stimulated. As supplies and personnel became available, areas were brought under control and rates dropped. After the use of DDT was instituted, still further reductions were noted, and finally, with employment of general Atabrine suppressive treatment in the more highly endemic areas, rates showed a further decrease. When all these various means were in operation, the rates dropped to a small fraction of what they had been in the early days of the China-Burma-India theater.

    As shown in maps 21 and 22, malaria is prevalent to a varying degree in practically all areas of the theater but was most prevalent in the areas with the largest numbers of troops--Upper Assam and north Burma. Surveys by malaria personnel and local civilian assistants substantially verified these findings.

Malaria in Prisoners of War

    Only a few prisoners of war were ever questioned by U.S. forces regarding malaria, but some captives from northern Burma revealed that malaria was very prevalent among the Japanese forces. Working through an interpreter, the following information was obtained: "Eight out of every 10 men had it." "They all had malaria at once." "Ninety percent had it." "Three out of every 10 men were sick with malaria at all times." "Some men had it 8 to 15 times, many had it 3 to 4 times."

    The British found that 6 of 19 prisoners from the 18th Division (which had been operating in Burma and China for some time) had malaria parasites in their blood (31 percent), and 3 out of 11 miscellaneous troops (27 percent).13 No evidence of malaria was found in 22 prisoners from the 45th Division. The British also received such statements from prisoners of war as "every soldier in Burma has malaria at least once."

    The number of items for prevention gathered from the battlefield, such as head nets, mosquito gloves, and repellents, indicated Japanese recognition of the problem and attempts at control.


    In early 1942, there was no specialized organization for malaria control in the theater. Control was a responsibility of individual commanders. Pre-

13 See footnote 8 (9), p. 357.
14 Unless otherwise indicated, data in this section are derived from: (1) Mantz, Frank A.: A History of Malaria Control Activities in the China-Burma-India Theater from July 1942 to July 1944. [Official record.] (2) Report, Maj. Mont A. Cazier, SnC, Headquarters, Services of Supply, U.S. Forces in China Theater, 10 Oct. 1945, subject: History of Malaria Control in the China Theater.


ventive measures consisted of unit malaria discipline and, in rare instances, of attempts by individual commands to carry out environmental control operations.

    In May 1942, the U.S. Public Health Service Medical Commission to the Yünnan-Burma Railway was sent to K'un-ming, detailed by the War Department for duty with the military mission to China. The Commission was assigned to Headquarters, Services of Supply, theoretically, to the Office of the Surgeon. However, urgent need for engineers for the construction of airfields necessitated the assignment of most of the sanitary officers to construction duties, with sanitation as a secondary duty. Soon, the Chief of the Commission, Lt. Col. Victor H. Haas, MC, became in effect the first chief of preventive medicine and malariologist for the theater. At larger U.S. Army installations, the chief sanitary engineer undertook general sanitary surveys, while the entomologists began malaria surveys. In time, these surveys gradually developed into control programs, insofar as limited trained personnel and extremely limited supplies permitted. During this period, supplies were procured by Services of Supply, wherever they were available, on recommendation of the U.S. Public Health Service. However, control depended chiefly on the starting of such permanent measures as draining and filling.

    As manpower wastage from malaria was considerable, the theater surgeon recommended the creation of a special organization for malaria control. The commanding general approved, and the position of theater malariologist was created and filled by February 1943.

    In the absence of theater directives, the officers of the U.S. Public Health Service outlined standard operating procedures to be established wherever they were assigned. In place of trained personnel, they persuaded commanding officers to detail small squads to carry out environmental control measures under their supervision. This system worked, but a precedent was established which later became troublesome. This disadvantage was that the preventive medicine malaria control program appeared to be entirely a Services of Supply operation. It was not intended that major commands in the theater should relinquish their responsibilities even though only Services of Supply had the personnel and supplies available to exercise control measures.

    When the War Department announced the organization of malaria control detachments, four such organizations were activated in the China-Burma-India theater, Initially, U.S. Public Health Service officers and casual Medical Department enlisted men available within the theater were to be used. This did not prove satisfactory, since these officers were attached to the U.S. Army from another service and could not assume command duties. As soon as possible, they were replaced by Sanitary Corps officers flown out from the United States.

    In March 1943, when the earliest phases of the malaria control program for the year were commenced, there had been a shift in the theater organization. This removed Services of Supply from the controlling position and


placed all personnel under the command of the theater surgeon. Malaria control and survey units, which began to arrive at the end of May 1943, were considered "theater" troops even though attached to and in effect operating under Services of Supply commands. 15

    The next organizational outline established for malaria control assigned final supervision to the theater rather than to Services of Supply malariologists.

    Services of Supply section commanders remained responsible for environmental antimalaria activities. They were required to use theater malaria control personnel, including the assistant theater malariologist, who were only attached to Services of Supply for administrative purposes and duty. This program was confusing to the personnel actually in the field. Those who were carrying out malaria control activities were not directly responsible to the commanders in the areas where they operated. These commanders could not deal with their operating personnel except through a separate and higher echelon.

    This objection was partially overcome on 7 August 1943, when the Commanding General, Services of Supply, was authorized to move personnel from one Services of Supply section to another, providing concurrence was obtained from the theater malariologists or his assistant.16 This still left a double line of administration. It did, however, give local commanders greater freedom in carrying out their responsibility for environmental control.

    Because of critical shortage of supplies, all items used in the control of malaria were brought under Medical Department jurisdiction.17 Requisitions were edited and distribution was made on the recommendation of the theater malariologist. The scale of issue was based on troop strength and relative malaria hazard in various areas. Further distribution of supplies was made by the assistant malariologist of these areas. The control of supplies was exercised far more diligently by the theater malaria control supervisors than was control over the units. This was due to the fact that the units were assigned to extremely large areas and that they could scarcely ever be in zones where the need for their services was not great. On the other hand, supplies were so scarce that strict care had to be maintained to see that they were distributed to critical points at critical times.

    This system was not without unwieldy characteristics. The intervention of two command headquarters between supervisory and operational antimalaria personnel sent all action a long way around before it went into effect. With the thought of eliminating some of the disadvantages and the dual command of administration, the theater malariologist drew up an outline for a "Malaria Control Regiment." Although interest in this idea continued until late in

15 Memorandum. Maj. Frank A. Mantz, MC, to Surgeon, Services of Supply, China-Burma-India Theater, 26 Jane 1944, subject: Critical Analysis of the Organization of Malaria Control in the China-Burma-India Theater.
16 Circular No. 42, Rear Echelon Headquarters, U.S. Army Forces, China-Burma-India Theater, 7 Aug. 1943, subject: Theater Directive on Malaria Control.
17 Memorandum No. 112, Headquarters, Services of Supply, U.S. Army Forces, China-Burma-India, 12 July 1943.


CHART 18.- Malaria control organization, Headquarters, China-Burma-India theater, 1943

1944, the more conventional forms of organization continued to be used. At the end of June 1943, the theater surgeons staff was further increased by the designation of four assistant theater malariologists.

    In December 1943, the title of malariologists was abolished by the theater commander and was replaced by that of medical inspector special (malariologist). The duties of this officer were as follows:

    Initiates and directs control measures to combat malaria; is consultant in matters pertaining to mosquito control; makes or initiates inspection of areas in which troops will be operating or quartered. Coordinates the work done by malaria survey teams and malaria control detachments; maintains liaison with and advises Quartermaster Corps and Corps of Engineers on supply requirements and aids In the procurement and distribution of antimalarial equipment and supplies. Maintains records and statistics on Incidence and control measures relative to malaria.

    By 1 January 1944, all U.S. Public Health Service officers engaged in the malaria control and preventive medicine programs had been returned to the United States, having rendered services of inestimable value to the U.S. Army.

    Until March 1944, malaria control organizations were administered directly from theater headquarters by the theater malariologist (chart 18). After this time, the theater malariologist was completely divorced from the control organization (Chart 19). He retained only the function of inspection, general


CHART 19.- Malaria control organization, India-Burma theater, after October 1944

planning, and recommendation. The remainder of the organizations took over independent operation in each of the several commands to which they were assigned. At this time an all-inclusive theater directive governing malaria control practices and policies was prepared by theater malariologists. According to the new directive, personal protective measures were to be enforced by command discipline. Services of Supply was made responsible for control of malaria and was ordered to direct its section commanders to take all necessary action. Procurement and issue of supplies remained with Services of Supply. Monthly reports of the malariologists in each Services of Supply section were to be sent to theater headquarters rather than to Services of Supply headquarters.

    The new arrangement was not satisfactory. The Air Forces protested that the new directive was contrary to established regulations in that it relieved unit and area commanders of their responsibility for the initiation and enforcement of malaria control measures. The practical disadvantage to the arrange-


ment. insofar as the Air Force was concerned, was that the deployed Army Air Force troops were likely to come under the jurisdiction of several different malaria control programs and agencies. With these objections Services of Supply agreed. While elements of malaria control and the activities of antimalaria units might conceivably be delegated to Services of Supply, it was not apparent how the Air Forces could be relieved of, or Services of Supply assume the responsibility for malaria education, discipline, and the enforcement of control measures. It was also obvious that since environmental measures were an integral part of the discipline, these activities could not be entirely divorced from other command responsibilities. Responsibility for coordination and advice was too completely removed from operations to bring the malaria control program to a high degree of effectiveness. A second defect was the lack of centralized or uniform policy.

    The solution to the problem was the consolidation of the staffs of the theater and the Services of Supply surgeons (General Orders No. 104, on 22 Aug. 1944). This merger solved the majority of difficulties which had arisen out of the confusion of command in technical channels of authority. In the realm of malaria control, the fact that Services of Supply had malaria control personnel assigned to it, while the theater had the malariologists and most of the other preventive medicine personnel, made little or no difference, since all members of the staff were unified under the direction of the deputy theater and Services of Supply surgeon. Even the formality of preserving the identity of the two staff sections became unnecessary in May 1945, when the Services of Supply was absorbed into a single theater command.

    The China area until October 1944, when it became a separate theater, was administered as one of the major sections of the China-Burma-India theater. After separation, a theater headquarters was established. In January 1944, a malariologist for the area was appointed. In March 1944, malaria control was made a function of Services of Supply. After October 1945, the duties of malariologist were assumed by the theater medical inspector. With limited personnel and equipment, control measures had to be confined to the larger installations.

    Although for a great portion of the time the various section commanders were responsible for malaria control measures and distribution of supplies, these functions were supervised either from Services of Supply or theater headquarters. These various section headquarters issued their own malaria control directives. In most major features, the directives were essentially similar, varying in minor respects, relating mainly to physiographic and biologic differences in malaria epidemiology.

    For all practical purposes, no great distinctions were made between forward areas and rear areas in regard to this program. As already stated, the Army Air Force installations had command responsibility for malaria discipline and such preventive measures, but the physical control measures were carried on by the troops assigned to Services of Supply. At this late date,


it is practically impossible to follow the eccentricities of the developing plans of the sections. Throughout the theater, the program was varied to meet the immediate needs of the problem at hand. The assistant malariologists in the various sections had free reign to make such modifications in existing programs as they deemed necessary for the adequate and prompt control of the disease.

    For the most part, the activities of malaria control in this theater were carried out by a self-contained organization. However, liaison with the Southeast Asia Command was permanently maintained. At times, the consultant malariologist for this command undertook special research in connection with the development of programs within the theater.

Extracantonmental Control

    From the beginning of the program, it was obvious that some extracantonment sanitary control was necessary if adequate protection was to be provided. It was recognized that this could not be carried out effectively by U.S. authorities because of the unusual relationship which existed between the Central and Provisional Governments; because of language difficulties, each area having a different dialect; and most important, because of religions customs which, for example, made impossible the spraying of the Moslem homes by a squad of "GI's." By working through General Headquarters,. India, the Central and Provisional Governments were contacted early in 1943, and they instituted a program of extracantonment environmental and sanitary control around many of the larger U.S. Army installations.18

    In the Calcutta area, two other procedures were followed. In some of the outlying areas, an arbitrary division was made so that U.S. forces controlled one side and British or Indian forces took care of the other. These projects were made effective by close liaison. In the large dock and warehouse district, control was placed in the hands of the Garden Reach Anti-Malaria Association. 19 This efficient, cooperative organization was paid to control certain areas and thus could augment its existing program to include the territory occupied by U.S. forces.

Antimalaria Details

    Under the authority of War Department Circular No. 223, dated 21 September 1943, and the India-Burma theater Circular No. 11, dated 31 January 1945, antimalaria details were formed in all companies and similar organizations. They carried out simple antimosquito measures such as maintaining mosquitoproofing, aerosol spraying, ditching, and larviciding. At times, they did the highly beneficial residual spraying (with 5-percent DDT) and mosquitoproofing within their own organizations. Their duties were

18 Letter, Additional Deputy secretary to the Government of India, to all Provincial Governments: The Agent to the Governor-General, Resident and Chief Commissioner, Baluchistan; The Chief Commissioner, Delhi, 11 July 1944, subject: Measures to Reduce the Risk of Infection to U.S. Army Forces Camps caused by Neighboring Villages.
19 Annual Report, Secretary, Garden Reach Anti-Malaria Association, Calcutta, 1944-45.


undertaken after preliminary training with the malaria control detachment or under the supervision of the battalion surgeon. These units were not at all times effective; for example, when the personnel were used for other duties and did not have time to attend to the malaria program. This was especially true where the medical section was made responsible for these activities.

    Most of these details should be described as antimosquito details rather than antimalaria details. Their work as a rule eliminated numerous breeding areas for pest mosquitoes. Most of the anopheline vectors of malaria did not breed in situations which the details controlled. However, their effectiveness in the overall picture should not be forgotten, because some malaria was undoubtedly prevented by their efforts.

Malaria Laborers

    Most of the malaria mosquito control projects required extensive labor, due to the topographical conditions and to the lack of available mechanical equipment. In order to facilitate the work, large numbers of laborers were employed. Most of them were hired by the Army and had had no previous experience with this type of work. Some were supplied by the Indian Tea Garden Association. In addition, India Pioneer Corps, Porter Corps, and Chinese Army troops were used. In many instances, they worked under the supervision of Indian Army units.

    When it was possible to retain the same personnel and to give adequate supervision, results were good. However, in some cases the personnel would not be the same from day to day, or at the most would only be retained for a very short time. Under these conditions, results were by no means as satisfactory. In a few areas, sufficient laborers were not available, and, as troop strength was always low, necessary operations suffered.

    Supervision of these workers was a serious problem. Even though they were for the most part employed as simple laborers, for example, to clear ditches, they had to be instructed. At first malaria control personnel were used as supervisors, but, as projects expanded, their numbers were not sufficient. At that time, personnel from other organizations, such as Quartermaster truck companies, and Quartermaster service companies, were used for this purpose. These men were not trained for the work, but members of the control organizations quickly showed them what was needed. In this way, some specially trained personnel could be released for other necessary work.

    In the Ledo area, another method of supervision was employed. Stationed in this area was an Indian Army antimalaria company, and it was arranged to have them take over a considerable portion of the supervision. This worked well, as the men had not only been instructed in the fundamentals of control but also did not have to contend with the language barriers that made supervision so difficult for U.S. troops.

    In the China theater, both Chinese troops and locally procured laborers were employed.


Organization for Airplane Spraying

    The first DDT air-spray experiment in the China-Burma-India theater was done with an L-4 cub plane equipped with Hausman-Longcoy accessories. It demonstrated that air spraying was effective against both larvae and adults, but the plane was too small for the job in this theater.

    Subsequently, in the India-Burma theater, the P-40, P-47, and B-25 planes were investigated. After experimentation, it was finally decided that the B-25 had the most desirable characteristics. It had the essential large carrying capacity, long range, and maneuverability. Some B-25 planes were therefore equipped with a 585-gallon bomb bay tank, an M-33 CWS discharge tube, with suitable outlet valve, and an operating lever. Experiments with this equipment indicated that under normal conditions the following results could be expected: (1) Each planeload of 585 gallons of 5-percent DDT solution could be spread over a swath about 200 yards wide and 9 miles long, and (2) the rate of dispersion across the swath would be reasonably uniform.

    By the fall of 1944, after 6 months of experimentation, an organization was developed, consisting of three B-25 planes modified for air spraying, six L-5 cub planes modified for air spraying, and two M-4 Chemical Warfare Service decontaminating apparatus, for mixing DDT solutions. The personnel were pilots and ground maintenance crews, two malaria control units, and one malaria survey unit. This organization was completed by February 1945 and continued in operation throughout the season. It was operated by the U.S. Army Air Forces under the name "India-Burma Air Spray Flight." Over 70,000 pounds of DDT were air sprayed in the form of 5-percent kerosene solution during its 9 months of activity (fig. 46).

    Experimental work led to the following conclusions: (1) When spray applications were followed within a few hours by rain, the effectiveness of the spray material was greatly reduced; (2) the continued low mosquito population in areas treated after 1 March 1945 was due to its early reduction during the premonsoon season; (3) in order to bring the mosquito population under control during the monsoon season, it was necessary to make applications more often than every 14 days or to use a higher concentration of DDT; however, no data are available on the effectiveness of a higher percentage of DDT; and (4) under the conditions of the experiments, the effective period following aerial application of 5-percent DDT was no more than 3 days.

    Air spraying was established in the India-Burma theater on the premise that it would supplement groundwork and be especially useful in rapidly controlling newly captured areas.

    There were certain basic organizational difficulties which were never completely overcome. The three major subdivisions of the theater were all interested and involved in this project. The U.S. Army Air Forces had the planes, pilots, and maintenance facilities. Services of Supply was responsible for malaria control; it had the antimalaria units that did the groundwork and


FIGURE 46.- DDT air spraying at Myitkyina, Burma

determined the needs for air spraying. The Northern Combat Area Command had an area of responsibility, antimalaria units on the ground, and occupied a rapidly fluctuating front that needed air spraying. The administrative problems were numerous and complex. The overall results obtained were as good as could be expected in a theater where distinction between air and ground forces authority was so sharply drawn. Ground-air liaison, although stressed by both sides as being one of the most important features of the program, was never effectively carried out. Even the simplest types of liaison attempted did not achieve any definite results. The inability of the air-spray flight to meet its commitments definitely hindered this phase of the program.

    Starting in August 1944, L-5 cub aircraft were used for air spraying in the China theater, around hostels occupied by U.S. troops. A 5-percent DDT solution was dissolved in a mixture of Chinese gasoline, 6 parts and kerosene, 4 parts. It was found that this mixture did not have a burning effect on rice and adjacent crops. Insufficient DDT was available to obtain adequate coverage.

    As the capacity and flight range of these planes was limited, efficient ground-air liaison was easily maintained.

Activities of Other Army Organizations

    Except for supply activities of the Quartermaster Corps and the Corps of Engineers and limited programs by various Army Air Force installations,


no other agencies were engaged in special antimalaria activities. The Air Force bases usually followed policies agreed upon between their surgeon and either the theater malariologist or assistant malariologist of the various sections. In these activities they were often helped by the malaria control personnel assigned to Services of Supply.

    At times, the Quartermaster Corps and the Engineer Corps were responsible for the requisitioning and issuing of the various malaria control supplies and equipment. As already discussed, for a time this responsibility was taken from them and given to the theater malariologist in order that more adequate and equitable distribution could be made.


Malaria Education

    Training. - No special technical and professional schools were maintained for antimalaria training. A few officers were assigned to take the general course at the Malaria Institute of India in Delhi. Some medical officers informally attended other established centers, such as the Calcutta School of Tropical Medicine. The opportunity for such instruction was unfortunately restricted by the capacity of the schools and by the limited personnel available for actual control work in the theater. Instruction of some of the enlisted men in malaria detachments was more easily accomplished at the various hospital and medical laboratories in which they worked. Training of this type, while greatly needed, was of necessity somewhat informal and erratic owing to the constant shortage of personnel.

    Formal education of the troops in malaria prevention was initiated following the publication, in September 1943, of War Department Circular No. 223, which required that all personnel in the Army undergo an intensive 4-hour course in malaria and its prevention. This course was to be given before overseas assignment. For those troops who were in the theater before the issuance of the directive, instruction was given in the field.

    Education of incoming troops started on the transport at the port of debarkation. Personnel were given a lecture on antimalaria procedure and reminded that they were entering one of the most malarious areas in the world. They were told how to protect themselves, and special emphasis was placed on the immediate problem of protecting themselves while traveling across India.

    At various times antimalaria personnel, either singly or in small groups, circulated through the theater contacting organizations. In lectures they explained the antimalaria program, answered questions concerning it, and checked the antimalaria campaign.

    Maj. Gen. (later Sir) Gordon Covell, Malaria Institute of India, lectured on the problem and its control at various locations within the theater. Attendance of at least one officer from each U.S. Army organization in the areas


was required at these lectures. This program was well received and was of definite help to all concerned.

    Organizations that reported a high malaria rate were visited by various antimalaria personnel. Inspections were made and problems discussed. When necessary, instructions were given to the malaria control officer, antimalaria detail, or at times, to as many of the command as could be gathered together. This was particularly important in relation to the DDT residual spray program. The result of these activities was better cooperation in the existing programs.

    Propaganda .- The bulletins of the various headquarters published all necessary information about malaria control. They were used to inform all personnel when changes were made or to emphasize some aspects of the program which were not receiving sufficient attention. These publications were used to prepare for the DDT residual spray program and air-spray operations. Various news sheets stressed the program with frequent short notices, warnings, and notes about changes in the program.

    Attractive posters were supplied for exhibition in dayrooms, on bulletin boards, in messhalls, and in orderly rooms. These stressed personal preventive measures, Atabrine (quinacrine hydrochloride) suppressive treatment, and other aspects of the program. Attempts were made to have the posters changed at frequent intervals in order to maintain their effectiveness.

    Radio reminders were used in the various GI radio stations. These varied from simple warning statements (several times daily) to short skits. At GI movies, antimalaria trailers were used with almost all shows. In addition, the various short films on malaria were shown at intervals throughout the theater. In connection with this, it might be noted that to enter a motion picture theater one was usually required to apply a repellent liberally. Road signs were used extensively from the port of debarkation to the gates of K'un-ming.

    In 1944 and 1945, the troops in this theater had a working knowledge of malaria and they were never allowed to forget it. Some propaganda methods were used so frequently, however, that their effectiveness was impaired.

Survey Activities

    Both entomological and parasitological surveys were conducted to obtain the necessary information concerning species of Anopheles, their distribution and habits, and their importance as vectors, and to determine the prevalence and types of Plasmodium. However, most malaria survey detachments within the area were actually engaged chiefly in control work. On the other hand, certain control detachments supplemented their work by survey activities.

    In areas where limited or no information was available, these surveys obtained sufficient data on which to base specific control measures. Unfortunately, records are not available to give a comprehensive summary of this work. The following record of the 35th Malaria Survey Detachment that was able to devote


its time to survey activities will give some idea of the extent of information compiled. In one year, more than 5,000 thick- and thin-blood film examinations (34.8 percent positive for Plasmodium) representing over 120 groups of individuals, were examined. More than 30,000 Anopheles larvae from over 1,300 positive collections and 5,500 adults from more than 350 groups of collections were identified by species. Over 2.500 mosquito dissections were made.

Mosquito Control Measures

    Larviciding . - Larviciding was one of the most important methods of malaria control and was utilized throughout the China-Burma-India theater. The availability of Malariol or other larviciding material and the ease of application by untrained labor added to the desirability of stressing this method. It was used extensively where other methods were not feasible, for example, in ricefields which could not be drained because of their essential food crops, in low flat areas which could not be drained satisfactorily, in water tanks (that is, reservoirs) essential to the life of villagers, and in breeding places requiring only temporary treatment or control only until more permanent measures could be put into effect.

    Although Malariol was used more extensively than any other larvicide in the India-Burma theater, paris green was used in China in many of the rice-fields, and white gasoline was sprayed in wells and in some tanks. When DDT became available, small amounts of it were dissolved in oil and this acted as a more effective larvicide. Smaller amounts of the DDT solution could be spread effectively over larger areas than could be controlled by simple oil sprays. In the China theater, waste motor oil and tung oil kerosene were mixed and extensively used as a larvicide. DDT dusting powder was found to be superior to paris green and was widely used to control mosquito breeding in ricefields. In addition to the ground larviciding, the air-spray program was established. It was found that this method was useful in large, flat, inaccessible swamp areas and also in quickly controlling the mosquitoes in newly captured areas. Effectiveness was definitely limited by rough mountainous terrain, which kept planes high, by dense jungle canopy, and by monsoon rains which frequently prevented routine operations or washed away the DDT immediately after spraying.

    Filling and clearing . - Filling for malaria control purposes was little used largely because of inability to obtain vehicles to transport fill and also because of lack of machinery to obtain material for filling.

    Clearing was done extensively in connection with drainage. In many cases this was the only method of revealing detailed topography so that drainage could be established. In addition, continued clearance of secondary growth in established drainage canals and other waterways was necessary so that larviciding and inspection crews could have access to mosquito breeding areas. For all these operations, simple handtools were all that were available


in the majority of cases; in some sections, however, powersaws were used effectively in clearing logjams and a right-of-way.

    In tanks (that is, earth-bunded reservoirs) for ground shortage of water, the situation amounted to a constant struggle to keep ahead of the abundant aquatic growth. Various methods were tried, but only two were at all effective, the first being hand cutting and pulling, and the second a method of dragging. In the latter, a drag was attached to the winch cable of a truck and this was pulled across the tank. Both of these methods were slow and, due to the very rapid growth, were only partially effective.

    Drainage. - Adequate drainage wherever possible and larviciding of other areas constituted the main antilarval operations. Literally hundreds of miles of drainage canals were dug and maintained by the malaria control detachments. In all but a very few areas, this work was done by laborers under the supervision of the control detachments or other personnel working for them.

    In some of the northern Burma areas, dynamite was used to establish drainage. This was an effective method and required much less manpower in an area where manpower was limited. Of course, labor was needed to maintain this drainage once it was established. No machines were available for ditching within the theater.

    Naturalistic control . - No attempts were made at regular flushing of waterways within the theaters. During the wet season, flash floods occurred frequently. For this reason, every effort was made to keep all drainage ways free from vegetation so that these torrents would be given full opportunity to flush breeding areas.

    In portions of the Calcutta area that were being controlled by the Garden Reach Anti-Malaria Association, tidal flushing was utilized.

    The U.S. Army did not attempt any naturalistic methods of control. In some villages surrounding various installations, however, the tanks, wells, and other waters had been stocked with larvivorous fish which helped to control mosquito breeding. It might be noted that in many areas tanks were used as commercial fish hatcheries. The fish undoubtedly helped reduce the mosquito population.

    Due to the enormity of the problem and to the lack of special equipment or time for much experimentation, few special methods were utilized in the theater. One special method used was assault boats fitted with power sprays to disperse larvicide in some of the rivers and larger lagoons.

    Adulticidal sprays . - Space spraying was carried out in buildings throughout the theaters whenever the necessary materials were available. Aerosol bombs, hand sprayers, and, at times, knapsack sprayers were used. Particular attention was given to barracks, messhalls, and latrines. The effectiveness of this method against flies led to its use in buildings where mosquitoes were not the primary problem. These activities were carried on by the organizations antimalaria details or by individuals within their own quarters. The frequency and thoroughness of such spraying depended upon efficiency of the


FIGURE 47.- DDT residual spraying in native quarters, using spray gun with power spray, vicinity of Ledo, Assam.

spraying crews. The proper method was outlined by the various malaria control directives.

    Limited space spraying outside of buildings was attempted. For a time, spraying of open-air movie areas was undertaken. However, before this had been fully organized, the DDT residual spraying program was established, and many of these areas were treated by the latter method. Space spraying was also accomplished by the air-spray program as the DDT in oil acted as a space spray as well as a larvicide.

    When quantities of DDT became available, an intensive residual spraying program was started. The details of application varied within the various sections of the theater. Village buildings within the supposed mosquito flight range were sprayed by the malaria control detachments, while in some areas they also sprayed troop quarters and other buildings. When the spraying of the very numerous local villages constituted a major problem, the spraying of military quarters was left to the organizational antimalaria details. These men were trained whenever possible by members of the malaria control detachments (figs. 47, 48, 49, and 50).


FIGURE 48.- DDT residual spraying in native quarters, using backpack spray with extension nozzle, vicinity of Ledo, Assam.

    The frequency of the spraying depended upon climatic conditions (as they influenced breeding and transmission), the scope of the program, and the amount of spray necessary for complete coverage. This program was stressed until it became the most efficient and probably the most effective portion of the antimalaria campaign. The relative ease of application, the duration of the spray deposit, and the readily visible effect on most insects won for it almost wholehearted cooperation.

    Mosquitoproofing . - Throughout the theater, the necessity for screening and mosquitoproofing was stressed. Due to a limited supply of materials, more were distributed, by order of the theater malariologist, to the areas of higher endemicity than elsewhere. Hessian cloth (burlap) and mosquito netting were used. During the early days of the theater, the entire supply was of British manufacture and was very scarce. During 1944 and 1945, large amounts of American-made netting and nylon and wire screening arrived to supplement the British stocks. However, it was not until midsummer of 1945 that sufficient quantities could be moved to the forward areas in Burma to meet the demand. Mosquitoproofing in the China theater was never adequate. The malaria control units distributed the mosquitoproofing supplies, supervised installation, and checked maintenance. Without this skilled assistance in the India-Burma theater, mosquitoproofing would have been much less effective.


FIGURE 49.- DDT residual spraying in native quarters, using hand spray, vicinity of Ledo, Assam.

    The standard materials were burlap (hessian cloth) for walls and ceilings and mosquito netting for doors and windows. The materials deteriorated rather rapidly in the jungle but were usually effective as long as the organization was stationary. Both the American pyramidal and the British EPIP (European Privates, Indian Pattern) tents provided comfortable living quarters when placed over a wooden framework, elevated to give 6-foot sidewalls, and then mosquitoproofed. Nylon and wire screening was used in relatively permanent buildings, such as hospitals and messhalls (fig. 51).

    Basha-type buildings (grass and bamboo construction) were often mosquitoproofed by native contractors under the supervision of malaria control personnel. This method was very effective, and as the men became trained in its use, efficiency was increased and waste decreased. In these more or less per-


FIGURE 50.- DDT residual spraying in latrine, using continuous hand spray and showing mosquitoproofing with mosquito netting and hessian cloth, vicinity of Ledo, Assam.

manent buildings, mosquitoproofing lasted for a considerable length of time (fig. 52).

    Maintenance of mosquitoproofing was the responsibility of the individual organization but was checked by malaria control personnel. In the areas where frequent movement of the organization occurred, there was considerable but unavoidable wastage.

    Bed nets and jungle hammocks were used throughout the theater. Early models of bed nets were of poor quality; they restricted air movement, and became rapidly mildewed. They were hot and smelly. Later models were made


of a tightly woven netting and were less objectionable. Little trouble was experienced in enforcing the bed net regulations. Jungle hammocks were used in forward areas until permanent quarters could be erected.

    Mosquito repellents . - Ample quantities of insect repellent began arriving in the China-Burma-India theater in the summer of 1943, and it became one of the few items of which the supply exceeded the demand. As the relative effectiveness of the various formulations became known, all but dimethyl phthalate were discarded and returned to Quartermaster stock.

    Repellents were universally objectionable to the troops, as they added to the general discomfort. They often smarted when applied to wind- or sunburned skin, they were sticky and oily, they made the user feel hot, they soiled clothes, and dissolved plastic. They were not used by the average soldier except under pressure from his commanding officer or when there were overwhelming numbers of mosquitoes. Various methods of using the repellent were tried with but fair success. In some sections of the theater, it was impossible to go to GI movies unless one submitted to a liberal application of repellent. While all individuals had repellent available and most believed in its effectiveness, its use was not as general as it should have been.

    Protective clothing . - Head nets and mosquito gloves were seldom if ever worn, They were extremely uncomfortable and restricted the efficiency of the


FIGURE 52.- Mosquitoproofing basha-type building, vicinity of Ledo, Assam.

wearer. In a few instances guards wore them but their use was soon discontinued entirely.

Atabrine Suppressive Treatment

    The history of Atabrine in the theater is a recapitulation of the general experience of the Army with this drug. Its use was characterized by the hesitation and vacillation common to all theaters during 1942 and early 1943. The therapeutic value of Atabrine was established and accepted by medical officers long before its suppressive properties were fully appreciated. Atabrine was used successfully in the hospitals in accordance with the suggestions and directives published by the Office of The Surgeon General, but no effort was made to employ the drug on a large scale for its prophylactic effects during the campaigns of 1943.

    Circular No. 5, published on 8 April 1943, contained this phrase: "*   *   * use of drugs for suppression of malaria symptoms, an emergency measure, to be employed only where other methods are impractical or inadequate, and dependent on military necessity when ordered by the commander concerned on the


advice of the chief surgeon concerned." Again, on 7 August 1943, theater directive on malaria control (Circular No. 42) stated: "*   *   * prophylactic administration of drugs against malaria is to be carried on only when directed by the theater commander."

    In the spring of 1944, when the Japanese hold in northern Burma was challenged, mass atabrinization of troops exposed to the malaria hazards of this hyperendemic area was started. The administration of one tablet of Atabrine daily was prescribed for "all American and Chinese troops operating in upper Burma forward of Shingbwiyang and west of Paoshan, Yünnan Province, China." 20 Some months later, the Atabrine zone was extended northward to include the extreme northern tip of Burma forward of the Tirâp River (some miles east of Ledo). In September 1944, it was decided to continue this suppressive program indefinitely. At the same time, units and individuals leaving these areas were directed to continue taking Atabrine for at least 4 weeks after departure.

    The early program of suppressive treatment was not successful. In July 1944, malaria reports from the Northern Combat Area Command recorded 5.8 percent of U.S. troops as malaria casualties (696 per 1,000 per annum). The causes were manifold--lack of understanding of the suppressive action of Atabrine, poor discipline and indifference, poor morale, and hostility to suppression caused by the belief that it lessened the soldiers practice of individual protection against mosquitoes.

    The belief that Atabrine suppressive treatment was detrimental to malaria discipline and to personal efforts to evade the mosquito persisted among many thoughtful and experienced malariologists throughout the remainder of the theaters existence. Once the idea was brought home to the soldier that faithful taking of one tablet of Atabrine a day would keep him from getting clinical attacks of fever, he became somewhat indifferent to the occasional mosquito bite that otherwise might have caused him real concern.

    Atabrine propaganda, to be effective, had to be dogmatic and forceful, emphasizing good features of the drug and minimizing its shortcomings and occasional undesirable side effects. This caused a certain amount of dissatisfaction among medical officers, especially those who questioned the intellectual honesty and scientific accuracy of such propaganda. The theater surgeons office was at times hard pressed to maintain its policy as laid down in official publications, when presented by evidence as to the occasional toxic effects of Atabrine.

    In December 1944, the theater surgeon, knowing that Atabrine discipline in the forward areas was not producing the desired suppression of clinical malaria, personally visited a large number of combat units and supporting elements then operating in the Bhamo-Lashio-Myitkyina area. The interest in Atabrine as a suppressive drug at that time is further demonstrated by an-

20 Circular No. 33, Rear Echelon Headquarters, U.S. Army Forces, China-Burma-India, 23 Mar. 1944.


other tour conducted independently by representatives of the Advance Section. It was inevitable, therefore, that the conference called by the theater surgeon in late December 1944 to revise malaria control policies should have been dominated by a desire to emulate the extraordinary success of the 1944 malaria control programs of the Australian and American forces in the Southwest Pacific Area. As a result of this meeting, India-Burma theater Circular No. 11 was published on 31 January 1945. This directive provided for the extension of the compulsory Atabrine suppression treatment to include most of the hyperendemic malaria areas in Assam, East Bengal, and all of Burma (comprising about 60 percent of the India-Burma theater strength during the period January through August 1945). This was a compromise between those who believed that suppressive treatment should be restricted to troops living continuously outside the protected areas and those who believed that there should be a blanket suppressive treatment covering the entire theater.

    On 28 January 1945, India-Burma theater Circular No. 4 was published. It was educational in form and purpose, containing a summary of the new work in the Southwest Pacific Area. It emphasized the absolute necessity of 100 percent daily Atabrine administration.

    By the middle of March 1945, the Atabrine program was fully established in the designated area. Its success, even beyond expectation, was due to a remarkable degree of command acceptance of responsibility for its execution. The low winter malaria rate continued on into the spring and summer and stabilized between 15 and 20 per 1,000 per annum. There was no appreciable summer or fall increase in malaria morbidity. The highest incidence of malaria in 1945 occurred in the Base Section outside the Atabrine zone, where the rates differed little from those of previous years.

    On 4 April 1945, China theater Circular No. 13 directed the use of Atabrine suppressive treatment in the more malarious areas of the command. Results similar to those in the India-Burma theater were achieved.

    The relative importance of the blanket Atabrine suppressive treatment compared with that of the efficient environmental mosquito control program carried out by China, Burma, and India malaria control detachments in bringing malaria under control will never be determined. That mosquito control was brought to an extremely high level of effectiveness during 1945 cannot be denied. Irrespective of relative effects of these factors, there remains one other factor that undoubtedly had a major influence on sick rates during the last 9 months of 1945. Except for traffic operations along the Stilwell Road and air support of British forces in central Burma, most of the U.S. troops, soon after the capture of Lashio in March 1945, quickly returned to a tranquil and orderly garrison life in well-policed and relatively mosquito-free areas.

    After an exchange of correspondence late in 1945 between theater headquarters and the new Intermediate Section, the Atabrine suppressive treatment


program was considerably modified. The main change was to put suppressive treatment on an optional basis in the large well-controlled troop concentration areas. This was because of the excellent state of mosquito control in these areas and because of the growing concern over the rising incidence of atypical lichen planus. The change was agreeable to all and appeared to be working reasonably well up to 4 December except for a mild increase of recurrent malaria in troops en route to ports of embarkation. Attempts to determine the total incidence of suppressed malaria in the troops living in the advanced sections were not particularly successful.

    On the debit side of the ledger must be recorded the occasional toxic reaction to Atabrine. Of the various conditions held to be due to Atabrine intolerance, the syndrome known as atypical lichen planus was the most important. The transient gastrointestinal upsets sometimes seen in the first week or two of suppressive treatment caused no serious concern. Likewise, Atabrine psychosis was of relatively little importance. Precise data on the occurrence of a-typical lichen planus in the India-Burma theater are not available. It is believed that the total number of cases was about 260.

    In August 1944, a malaria commission for instituting research in malaria was established. It was to deal chiefly with the chemical problems connected with Atabrine therapy. Unfortunately through lack of cooperation, the commission was broken up on arrival. Early in January 1945, it was established at the 20th General Hospital in Ledo, Assam. One of the chief aims was to develop a simple urinary chemical test that would indicate the concentration of plasma Atabrine by using a technique developed by the British and described in Interim Report No. 27 of the Malaria Research Unit, November 1944. A paper describing this research was forwarded to The Surgeon General on 16 August 1945. This work was well received and proved to be of value to commanding officers in enforcing the Atabrine program.

Field Research

    Various malaria control detachments carried out field research on the methods of applying DDT residual spray. Considerable time was spent trying to develop more effective and efficient sprayers for this work. In most cases, this involved modifying existing equipment.

    In connection with the DDT air spray, much field study was done, primarily to obtain information regarding distribution of material, droplet size, and results of various meteorologic conditions upon both the spray and the effects of the spray. Other experiments in conjunction with this work were made to try to determine the effectiveness, penetration, exposure, and time before maximum kill.

    The various survey detachments, whenever they were able, did considerable research work concerning the biology of the various anopheline mosquitoes


within their areas. With the finding of infected A. leucosphyrus within the area, a great deal of time was spent in trying to determine the importance of this species as a vector.

Other Activities of Malaria Control Personnel

    Early in the theater history there was a tendency to use malaria control organizations for duties other than their primary mission. This was stopped by a letter to the commanding generals of all major commands in August 1944. From that time on, malaria control organizations officially devoted all of their time to their immediate mission.

    At times, their advice or cooperation was secured in other problems as, for example, fly control. Some of their equipment and supplies were expended for this purpose; personnel, however, were not diverted for this use. For a certain time, personnel were withdrawn for entomological investigations of a reported epidemic of sandfly fever at Gayâ, Bihar Province, India.21 This was because malaria control personnel were the only qualified individuals to conduct such an investigation. In a number of instances, also, malaria control personnel gave advice or checked on water supply installations. They also handled the supplies for the prevention of scrub typhus. As the supplies were the same as those used for malaria control, it seemed advisable that their distribution be centralized. This worked efficiently. In making routine surveys, other features of sanitation were often checked. In these cases information was usually passed orally to the organization involved or to the sanitary inspector for the section in which the violations occurred. In addition, personnel in these organizations with special qualifications were consulted, when it was thought their advise would be helpful, concerning other problems within the theater.


    Most of the areas in China, Burma, and India occupied by the U.S. Army were malarious; the intensities of infection varied from slight endemicity to hyperendemicity on a scale as high as any in the world. Living conditions were often primitive, and local populations were largely uneducated, so that, except in limited areas, little or nothing had been done to prevent the disease. Efficient malaria control, therefore, had to be established by the Army in order to maintain its effectiveness.

    Malaria control activities were undertaken throughout the occupied sections. Practically all known means of control were utilized, the actual type

21 Letter, Capt. John W. H. Rehn, SnC, 9th Malaria Survey Detachment, to Commanding General, Headquarters, U.S. Forces, India-Burma Theater, 4 Sept. 1945, subject: Sandfly Investigation in the Gayâ Area.


and scope depending upon the immediate needs of the area and the supplies available. These included standard and modified antilarval and antiadult mosquito control methods, supported by personal preventive measures and, in certain areas, by suppressive medication.

    Because of the great variety of conditions encountered, a highly centralized malaria control organization was not practicable. Organization eventually developed along distinctly sectionalized lines, with ample authority being delegated to sectional malaria control groups for dealing with local situations by the best available means.