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Part 7

Table of Contents


The Spanish-American War-
Tropical Preventive Medicine


Only 118 days of hostilities were needed in the war between the United States of America and the Kingdom of Spain to create incredibly momentous changes in the affairs of the world. During this period, from the declaration of war on 21 April to the surrender of Manila on 16 August 1898 (4 weeks after the fall of Santiago, Cuba), Spain lost its vast possessions in Cuba, Puerto Rico, the Caribbean region, Guam, and the Philippine Islands (150). The hitherto continentally centered isolationist United States, through mastery of those dominions, sailed out into the oceans as a world power. From this war, enormous and multiform consequences developed, many of which affected medicine and public health. Of these consequences, a few which importantly influenced the further evolution of civilian and military preventive medicine will be considered here.

Some medical aspects of the war with Spain.-In terms of men engaged and battles fought, the size of this war with Spain was small. However, the rapid assembling of a force nearly 10 times as large as the peacetime Army confused and taxed all bureaus of the War Department to the utmost. At the outset of the war in April 1898, the strength of the Army was 28,183 officers and enlisted men. In May 1898, the United States Army had been increased to



163,592, and reached 265,629 in July. The peak strength in August was 272,618.

Sickness and mortality.-Statistics of losses vary partly because the periods taken as bases for computation vary. According to figures supplied by the Medical Statistics Division of the Office of The Surgeon General on 22 June 1954, during the period of hostilities, the total deaths were 2,430. Of these, 369 were battle casualties (266 killed in battle; 103 died of wounds). The number of men who died of disease in this period was 1,939, mostly in the camps of volunteers in the United States as a result of typhoid fever. Sternberg, computing on the basis of the calendar year, May 1898 through April 1899, recorded 968 battle casualties and 5,438 deaths from disease. The mortality rate from disease was 27.13 per 1,000 mean strength per annum, and the ratio of deaths from disease to battle deaths was 5.6 to 1. (Some compute this ratio as 7 to 1.)

In Cuba, in addition to a small amount of typhoid fever, the diarrheas and dysenteries, malaria, and yellow fever attacked the troops almost as soon as they landed. The whole experience, including the gastrointestinal disorders from the eating of "embalmed beef," was one of such appalling sickness that the dissolution of the Army by disease was feared, and this forced a rapid withdrawal of soldiers from Cuba soon after the end of hostilities.

The work of the Medical Department during the Spanish War, together with an abundance of medical and sanitary data were copiously presented by Surgeon General Sternberg in his annual reports for 1898-1901, and in other publications (151).

The principal lessons to be derived from the experiences recorded in these reports were stated by Surgeon General Sternberg essentially as follows (152):

1. A trained medical corps of a small army can not control the sanitary situation when the army is quickly and largely expanded.

2. Physicians and surgeons from civil life, however well qualified professionally, as a rule are not prepared to assume the responsibilities of medical officers charged with



administrative duties and the sanitary supervision of camps.

3. Training and discipline are essential factors in the preservation of the health of soldiers in garrison or in the field.

4. Preparation by training and by systematic instruction in military medicine and hygiene, especially in camp hygiene, for both line officers and medical officers is essential. Preparation is a primary principle of preventive medicine, "In time of peace prepare for war."

Typhoid fever in military camps in the United States.-Typhoid fever broke down the strength of the commands generally through extensive prevalence among troops encamped within the limits of the United States during the months of May through September 1898. To investigate and report on the origin and spread of this disease, and on many related medical and sanitary matters, The Surgeon General in August 1898 secured the appointment of a board of medical officers.

The Reed-Vaughan-Shakespeare Typhoid Board.-The board was composed of Walter Reed, Major and Surgeon, U.S. Army, Victor C. Vaughan, Major and Division Surgeon, U.S. Volunteers, and Edward O. Shakespeare, Major and Brigade Surgeon, U.S. Volunteers. This board, known from the names of its members as the Reed-Vaughan-Shakespeare Board, carried out clinical, epidemiological, and etiological investigations, and rendered a famous report. Actually, the board published three versions of its report which are listed in chronological order (153). (Excerpts from the second version of the report are reprinted in appendix B, p. 193.)

Investigations and report.-Material for the investigation was abundant. The total number of probable cases of typhoid fever among the 92 regiments studied was 20,738. Of these, 1,580 soldiers died, giving a death rate of 7.6 percent. The Reed-Vaughan-Shakespeare Board found among other things that:

1. The waterborne factor was not as important for the spread of typhoid fever as previously believed.



2. The spread of the disease was mainly by contact between persons, and by flies.

3. Human carriers (sick, immune, or well) of typhoid bacilli were important sources of typhoid infection.

"Report" (1899) and "Abstract of Report" (1900).-This point deserves emphasis. Walter Reed and his associates may not have known much about carriers when they started this investigation, but by the end they were able to make clear and strong statements on this subject. The following examples are cited from the "Report" and the "Abstract":

1. A man infected with typhoid fever may scatter the infection in every latrine in a regiment before the disease is recognied in himself. * * * The elimination of typhoid bacilli from the bowels probably begins soon after infection. If this be true, during the incubation period an individual may be a source of danger to others. Moreover, in most instances of typhoid fever the disease is not recognized in the prodromal stage, and during this time the excretions may be laden with typhoid bacilli. [Rep. (14), p. 663.]

2. Persons recovering from typhoid fever may continue for many weeks to eliminate in the urine millions of the Eberth bacillus. [Ab., p. 201.]

3. The typhoid bacillus may grow in the intestines of an individual and pass from the same without causing typhoid fever. * * * It is certain that an individual may become the bearer and distributor of the infecting agent of typhoid fever without developing the disease himself. [Ab., p. 202.]

4. The specific germ of the disease may be transported from one place to another in the intestines of an immune man, and when cast out in the stools may become a source of danger to others. It is probable in some such way as this that epidemics of typhoid fever sometimes appear to originate de novo. [Ab., p. 202.]

Typhoid carriers.-Historians, such as Ashburn, have either failed to read completely the text of the Reed-Vaughan-Shakespeare documents, or have misrepresented some of the statements. Some have written that while the important parts played by man-to-man transmission and



by the fly as an agent in the spread of typhoid fever were established by these investigators, the role of the human carrier was not appreciated at that time. For example, Ashburn's (154) comments were:

Nobody knew anything about typhoid carriers. Nobody appeared to realize that men in the early stages, even in the incubation period of the disease, might be eliminating vast numbers of typhoid bacilli. * * * these facts * * * strongly suggest to the writer that the Reed-Vaughan-Shakespeare Board, the Medical Department, and the medical profession missed the best bet of the day.

This may have been true, to some extent, of the Medical Department and the profession. It is certainly not a fair statement of the insight and views of the Board. Indeed, if the Board had been heeded, the importance of carriers in the spread of typhoid fever would have been widely recognized as early as 1900, and the discovery credited to research in preventive medicine by medical officers of the United States Army.

The Dodge Commission Report (1899).-In the Spanish-American War, the Medical Department of the Army was inadequately equipped, both in personnel and material, to meet its obligations. Although much good work was done with inadequate means available, the Department was severely criticized, as was the whole War Department. On 8 September 1898, shortly after the close of the war, to get at the facts, President William McKinley, at the request of R. A. Alger, Secretary of War, appointed a commission to investigate the conduct of the War Department in the war with Spain. This commission, called the "Dodge Commission," after the name of its able president, Maj. Gen. Grenville M. Dodge, USA (Ret.), held 109 meetings, considered a vast amount of testimony, and rendered its report on 9 February 1899 (155).

Army Medical Department reorganization.-In this influential report, which led eventually to a reorganization of the Army, there was published a large mass of testimony from all available sources concerning the Medical Department, with conclusions and recommendations. Brig. Gen. Robert Maitland O'Reilly, Surgeon General of the



Army from 1902 to 1909, and his assistants "accepted the conclusions of the Commission * * * as established facts, and its recommendations as an official and authorized statement of the future policy of the medical department." Indeed, this portion of the Dodge Commission Report was regarded as a charter for a reorganized and improved Medical Department. Surgeon General O'Reilly devoted his entire administration to the fulfillment of this charter. At the end he could report (156): "the deficiencies have been almost wholly corrected."

The Congress passed laws to implement some of the recommendations of the Dodge Report. The War Department and its bureaus took appropriate action. The Medical Department moved in its field. Much of this activity had direct and indirect effects upon the organization and operation of preventive medicine in the Army. Emphatically, the commission had pointed out that because of the absence of a special corps of inspectors and the infrequency of inspections by chief surgeons "there was not such investigation of the sanitary conditions of the army as is the first duty imposed upon the [medical] department by the regulations." The remedy of sanitary deficiencies and the prevention of their reoccurrence thus received a strong impetus.

Among the legislative acts beneficial to the Medical Department and through that to preventive medicine were:

1. The establishment of a General Staff Corps and a Chief of Staff, with whom The Surgeon General could communicate directly.

2. Reorganization and redefinition of the Medical Department of the United States Army-which "from and after the approval of this Act [Act of April 23, 1908 (35 Stat. 66)] shall consist of a Medical Corps and a Medical Reserve Corps, the Hospital Corps, the Nurse Corps, and Dental Surgeons (later in 1911, a Dental Corps), and provisions for paid veterinarians in 1901, and later in 1911, a commissioned Veterinary Corps."

3. Establishment of a Medical Reserve Corps by the Act of April 23, 1908, providing for a large group of highly



qualified physicians, surgeons, scientists, and specialists of many types from which essential skilled personnel could be drawn in times of need. Hundreds of officers who have contributed valuable services to preventive medicine in the Army have come from the Medical Reserve Corps.

Boards for the study of tropical diseases.-As a result of the Spanish-American War, the United States Army became one of the responsible agencies of the government in the administration of civil affairs-military government in such tropical dependencies as Cuba, Puerto Rico, and the Philippine Islands. The related and inevitable public health activities were urgent, novel, and replete with unsolved problems. Diseases peculiar to the tropics, and most of the diseases of temperate zones, were widespread among the inhabitants of these countries. They were a menace to the armies of occupation and a hindrance to the development of these regions. At that time, in 1898, little was known about the causes or the control and prevention of tropical diseases, although there was important basic new knowledge about the transmission of some diseases through biological processes of life cycles of protozoan parasites in arthropods. The transmission of malarial fevers by anopheline mosquitoes was proved by the results of the investigations of Sir Patrick Manson (fig. 25) and Sir Ronald Ross (fig. 26) during the years from 1894 to 1898. By 1893, in the veterinary field, Theobald Smith (fig. 27) and F. L. Kilborne had demonstrated the transmission of Texas fever of cattle by a tick. Keenly aware of the need to acquire essential knowledge, Surgeon General Sternberg, skillful in the selection and utilization of research teams, with characteristic foresight and initiative, obtained in 1900 the appointment by the War Department of two boards of medical officers to study tropical diseases in the places they occurred. The first was a board to study a variety of diseases, especially tropical diseases, in the Philippine Islands. The second was appointed for the purpose of investigating infectious diseases in Cuba, giving special attention to the etiology and prevention of yellow fever. Some account of these boards will be given to exhibit types of their scien-



FIGURE 25.- Sir Patrick Manson (1844-1922), the "Father of Modern Tropical Medicine." In 1877, he demonstrated that the filaria of elephantiasis develops in, and is transmitted by, the Culex mosquito. This was the first proof of the spread of infection by an insect vector. In 1894, he announced his mosquito-malaria hypothesis. He became the inspirer and mentor of Ronald Ross. (Photograph portrait, courtesy of the National Library of Medicine, photograph negative No. 105547.)

tific contributions, and to signalize them as powerful mechanisms for the advancement of preventive medicine in the Army and in its civilian environment. It was a mechanism of which General Simmons, follower of Sternberg and a member of some of these boards in their early days, made effective use during World War II (157).

Army Medical Research Boards in the Philippines (1900-1933).-During the 33 years, from 16 January 1900 to the end of 1933, except for a gap from 1902 to 1906, there was a succession of three United States Army Medi-



FIGURE 26.- Sir Ronald Ross (1857-1932). While in the Indian Medical Service, he demonstrated that an Anopheles mosquito was a vector of malarial fever, and later devised malaria control procedures based on antimosquito measures. (Portrait photograph, courtesy of the National Library of Medicine, photograph negative No. 32.497.)

cal Research Boards in operation in the Philippine Islands, with headquarters in Manila. These boards investigated many types of diseases prevalent in those Islands. In accordance with directives issued from time to time by the incumbent surgeon general, these boards were not restricted to investigations of diseases of human beings; they studied also diseases of cattle and other animals. The range of subjects of interest was broad, and the investigations were concerned with the biology and pathogenic



FIGURE 27.- Theobald Smith (1859-1934). One of the pioneers in the investigation of infectious diseases, be demonstrated in work with Kilborne that the protozoan parasite of Texas cattle fever was transmitted by a tick, providing another early convincing proof of an insect vector of communicable disease. His original description of anaphylaxis was called the "Theobald Smith phenomenon." (Portrait photograph, courtesy of the National Library of Medicine, photograph negative No. 6290.1.)

effects of practically all the classes of parasites. Medical entomology and metabolic disorders of man received a large share of interest. Among other subjects there were investigations on dysentery, cholera, and plague by 1st Lt. Richard Pearson Strong, MC (fig. 28), investigations on dengue by Lt. Col. J. F. Siler, MC, Maj. Arthur P. Hitchens, MC, 1st Lt. Charles F. Craig, MC, and Capt. James S. Simmons, MC. Craig and Ashburn showed that dengue fever was caused by a filterable virus, and Siler,



FIGURE 28.- Richard Pearson Strong (1872-1948). Long a member of the professorial staff of the Harvard Medical School, he was President of the Board for Investigation of Tropical Diseases in the Philippines (1899-1901). He conducted researches on many communicable diseases in many countries, including plague in Manchuria and typhus in Serbia. He was the author of a vast treatise on tropical medicine, conducted the course in tropical medicine at the Army Medical School during World War II, and served as an adviser to the Preventive Medicine Service, Office of The Surgeon General. (Portrait photograph, courtesy of the National Library of Medicine, photograph negative No. 10.777-A.)

Hitchens, Simmons, and others added much to the knowledge of the transmission of dengue by mosquitoes, chiefly, Aedes aegypti. Capt. E. B. Vedder, MC, made classical studies of beriberi. Capt. Raymond A. Kelser, VC, developed a vaccine against rinderpest in water buffalo. There were many important investigations on malaria. Nearly all of the



medical and veterinary officers who were members of these boards became leaders in various fields of preventive medicine in the United States Army during a period extending even to the end of World War II (158).

Yellow Fever Board in Cuba (1900-1901); Reed, Lazear, Carroll, and Agramonte.-The second Army Medical Research Board, selected and established through the efforts of Surgeon General Sternberg, was appointed by the War Department on 24 May 1900 chiefly for the purpose of investigating, in Cuba, the cause, mode of spread, and prevention of yellow fever. Its president was Maj. Walter Reed (fig. 29), after whom the unit became known as the Walter Reed Yellow Fever Commission. The other members, able, original, courageous, indefatigable like their leader, were Drs. Aristides Agramonte, James Carroll, and Jesse Lazear. Working at Camp Columbia, at Quemados, and in Havana, the Reed Commission performed scientific miracles in a single year's span, 1900-1901.

Carlos Finlay and mosquito transmission of yellow fever.-The Reed Commission proved that yellow fever was caused by a filterable virus and confirmed the hypothesis of Carlos Finlay that the disease was transmitted by a mosquito (Aedes aegypti). By working out the cycle of the virus in man and mosquito, and by many other discoveries, the members of the Commission established principles and procedures that were to become determinative not only for the control and prevention of yellow fever by antimosquito measures (see appendix C, p. 201) and by immunization of human beings, but also for the whole category of insect-borne diseases. They made possible such gigantic accomplishments as the digging and building of the Panama Canal.

The dramatic story of the conquest of yellow fever of the urban type by Walter Reed and his associates is so well known that it is unnecessary to give further details here. Suffice it to cite a number of references to official, scientific, and biographical publications (159).

An opinion expressed by Dr. William Henry Welch is an appropriate evaluation (160). After saying that Walter



FIGURE 29.- Walter Reed (1851-1902), investigator of typhoid fever and typhoid carriers in Army camps in the United States in 1898, during the Spanish-American War. He was the planning and guiding force of the Yellow Fever Commission in Cuba in 1900-1901 which demonstrated that yellow fever was transmitted by the mosquito Stegomyia fasciata, later named Aedes aegypti. On the basis of findings he described measures for the control, prevention, and possible eradication of yellow fever. (Portrait photograph, courtesy of the Armed Forces Institute of Pathology, photograph negative No. WW-2545.)

Reed's contribution was comparable to Edward Jenner's he said: "The commission proved that complete eradication from the face of the globe of the greatest and most dreaded pestilence that affects mankind is possible. * * * It was an inestimable service to mankind."

In his draft "Introduction," previously referred to, General Simmons wrote: "This single contribution by the U.S.



Army to our basic knowledge of yellow fever stimulated the subsequent extensive researches of the Rockefeller Foundation and others, which have provided so much important information about yellow fever and have afforded the effective vaccine now used to protect American troops against this disease."

Hookworm disease in Puerto Rico; Ashford's work.-While stationed at Ponce, Puerto Rico, in 1899, 1st Lt. Bailey K. Ashford, MC, Assistant Surgeon, United States Army, began the study of "the severe anemia so common among the poor of this island." He found great numbers of the ova of the hookworm, Ancylostoma duodenale, in the feces of patients and proved that "Porto Rican anemia" or "tropical anemia" was caused by infestation of this parasitic nematode, to which attention had been directed by Dr. Charles Wardell Stiles, "the professor of helminthology at the Army Medical School," and a teacher of Lieutenant Ashford there in 1898. This work led to the worldwide campaign of the Rockefeller Foundation for the control of hookworm disease (ancylostomiasis). It strengthened the position of helminthology as a discipline of preventive medicine (161).


Energetically animated by the brilliant discoveries and achievements just described, modern scientific preventive medicine advanced rapidly during the first 16 years of the 20th century. The period from the windup of the Spanish-American War in 1901 to the entry of the United States into World War I on 6 April 1917 was one of accelerating progress in preventive medicine in the United States as it was in Europe, both in civilian communities and in military organizations. Accompanying the scientific and administrative gains, and the appreciation of their immediate and potential power, a sanitary conscience was aroused. An impetus was imparted, which continues to



this day, to push forward the movement for improvement in military health.

Tropical medicine.-Epoch-making biological and sanitary work was done by Army medical officers in the tropical territory opened to the United States by the Spanish-American War. In praise of this period, Meleney (162) wrote in 1942:

The Golden Age of Tropical Medicine in United States history was the first two decades of the present century, when yellow fever, malaria, hookworm, typhoid and the dysenteries were largely brought under control. Representatives of our Army and Navy Medical Corps and the U.S. Public Health Service were very important factors in this work, and the Bureau of Science in Manila gave experience to many men who have become our leading authorities on tropical medicine.

Highly important in tropical medicine were the convincing demonstrations of arthropod vectors of some of the chief diseases (malaria, yellow fever, filariasis, dengue), and the recognition of the seminal function of human and animal carriers of the agents of infectious diseases.

Havana freed from yellow fever and malaria reduced.-Early in 1901, the Chief Sanitary Officer of Havana, Cuba, Maj. William Crawford Gorgas (1854-1920) (fig. 30), accepted the evidence provided by the Walter Reed Commission that the mosquito, Stegomyia fasciata (Aedes aegypti), was the sole transmitter of yellow fever (163). He was aware also of the recently proven transmission of malaria in man by anopheline mosquitoes. Therefore, with vigor and full support of General Leonard Wood (1860-1927), Governor General of Cuba, he attacked with two antimosquito brigades-an anopheles brigade and a stegomyia brigade. With the anopheles brigade, he achieved some reduction in the prevalence of malaria. With the stegomyia brigade, lie drove yellow fever out of the city. Whereas in in the previous year, there had been approximately 300 deaths from yellow fever in Havana, after 26 September 1901, not a single case occurred. This was the first triumph over an insectborne disease of man based upon bionomics of the vector and knowledge of the cycle of the parasitic



FIGURE: 30.- William Crawford Gorgas (1854-1920), Surgeon General of the United States Army (1914-1918). Applying methods based on the findings of the Walter Reed Commission he cleared Havana of yellow fever and, with a broad program of sanitation and disease control, made possible the building of the Panama Canal (1904-1914). (Portrait photograph, taken in 1901 when as a major, Medical Corps, he was Chief Health Officer of Havana, Cuba. Courtesy of the National Library of Medicine, photograph negative No. 54-184.)

virus. It is to be recalled, however, that the first control of an arthropodborne disease by attack on the vector was the prevention of tickborne Texas fever in cattle by Theobald Smith and F. L. Kilborne as the result of work begun in 1888 and published in 1893 (164). The measures were simple, but their application and enforcement required hard work. With regard to yellow fever, the three main



preventive-control measures were: (1) prevention in every possible way of the breeding of aegypti mosquitoes in flowerpots, rainwater barrels, cisterns, fishponds, and collections of water in domestic environments; (2) prevention of mosquitoes from biting yellow fever patients (screening), and (3) destruction as far as possible of all mosquitoes that had bitten yellow fever patients (fumigation of rooms and premises).

Disease control and building the Panama Canal (1904-1914).-The construction of the Panama Canal was an Army job, carried through to completion in the 10-year period, 1904-1914, mainly by two branches of the Service-the Corps of Engineers and the Medical Corps. It is generally agreed that sanitation and preventive medicine under the direction of Col. William Crawford Gorgas, MC, formed the foundation upon which the engineers were able to build the Panama Canal (165).

After his success in freeing Havana from yellow fever, in 1901, Colonel Gorgas surveyed conditions in Panama. He made it clear to Surgeon General Sternberg and other authorities that yellow fever, malaria, and certain other diseases so prevalent in the region would enormously hamper the work, and possibly defeat the United States' effort as they had destroyed the French, unless the new control measures that he had devised in Cuba were adapted to the Panamanian situation and rigorously applied. He was appointed Chief Sanitary Officer of the Panama Canal Zone in 1904 and at once set about his transforming work. In spite of the lack of full understanding and opposition of the engineers, he succeeded in freeing the Canal Zone of yellow fever in two years; the final indigenous case occurred there in May 1906. Malaria was greatly reduced by a variety of large-scale antimosquito measures, such as ditching, draining, larviciding, fumigating, and screening. The pesthole of Panama, the "White Man's Grave," was changed to one of the healthiest communities in the world (166).

In evaluating the accomplishment, Colonel Gorgas claimed that during the building of the Panama Canal the Sanitary Department had been the agency for the saving



of 71,370 human lives and the prevention of a vast amount of disability from sickness. More than this, he saw in the results the fulfillment of a cherished ideal in his geopolitical concept of preventive medicine. This was the demonstration that sanitation and preventive medicine would make it possible for the white man to thrive in the bounteous tropics. Finally, he wrote (167):

The discovery of the Americas was a great epoch in the history of the white man, and threw large areas of fertile and healthy country open to his settlement. The demonstration made at Panama that he can live a healthy life in the tropics will be an equally important milestone in the history of the race, and will throw just as large an area of the earth's surface open to man's settlement, and a very much more productive area.

Antityphoid vaccination.-Although typhoid fever among the troops of the United States Army declined to a low "normal" incidence after the severe epidemic of 1898, the dread of a resurgence of the disease continued. In discussions of the problem of control, Maj. (later Brig. Gen.) Frederick Fuller Russell, MC (1870-1960) (fig. 31), was one of the medical officers who were strongly of the opinion that there was a need for some method of preventing typhoid in addition to what the Army had available-some new measure that promised to give protection under all sorts of conditions, especially wartime conditions. Influential in raising the spectre of the disease was the experience of the British Army in the Boer War (the South African War), 1899-1902, in which that Army had 31,000 cases with 5,877 deaths from typhoid fever. It was during this war, however, that a new protective measure was devised and tested by Sir Almroth Wright (1861-1947); namely, antityphoid vaccination by subcutaneous injection of killed typhoid bacilli into soldiers. The method appeared to be successful, and, in 1908, Major Russell was sent abroad to study it. After his return in January 1909, his report was received favorably by a board of distinguished members of the Army Medical Reserve Corps. The procedure was approved and adopted for introduction in the Army (168).



FIGURE 31.- Frederick Fuller Russell (1870-1960). In 1909, after making observations abroad, be introduced antityphoid vaccination in the United States Army. (Portrait photograph, courtesy of the Armed Forces Institute of Pathology, photograph negative No. WW-3041-A.)

Vaccination against typhoid fever, applied in limited stages in 1909, was made compulsory for the whole Army in 1911. At that time; and for several years thereafter, there were maneuvers of large bodies of troops in Texas, Arizona, southern California, and along the Mexican border. The sequel was spectacular. Vaccination with killed suspensions first of the Rawling's strain of the typhoid bacillus alone and later with a triple vaccine containing also paratyphoid A and B bacilli, was followed by a great reduction in admissions for typhoid, and in mortality from the disease. During one remarkable year, as reported by



FIGURE 32.- Joseph Franklin Siler (1875-1960), noted for investigations of mosquito transmission of dengue fever in the Philippines, for commanding the Laboratory Service in the American Expeditionary Forces in France in World War I, and for extensive experimental observations on the manufacture and immunizing efficacy of antityphoid vaccines. (U.S. official portrait photograph of Colonel Siler in his office at the AEF Central Laboratory, Dijon, France, 1918. Courtesy of the National Library of Medicine, photograph negative No. 28194.)

Siler (fig. 32), there were only 8 cases in a force of 100,000 in the field and no deaths (169).

Most medical officers saw in these results an example of direct cause and effect. More critical officers, however, have pointed out that coincident with antityphoid vaccination there have been many improvements in many elements



FIGURE 33.- Carl R. Darnall (1867-1941), deviser of a method of purification (sterilization) of drinking water by treatment with anhydrous chlorine. (Portrait photograph, courtesy of the Armed Forces Institute of Pathology, photograph negative No. 519-1210-122.)

and facilities for sanitation of camps, marshes, and field positions. At the time of World War II, there were still unanswered questions as to the true efficacy of typhoid vaccination, but the evidence was regarded as sufficiently favorable to warrant its continued use, and the procedure had become "traditional."

Chlorination of drinking water by Darnall.-In addition to the activities of the Army Medical Research Boards in Cuba, Puerto Rico, the Philippines, and the work done in Panama, research by individuals elsewhere produced valuable results. The years 1910 to 1913 were especially fruit-



FIGURE 34.- William John L. Lyster (1869-1947), inventor of the "Lyster bag" in which drinking water may be sterilized in the field by addition of calcium hypochlorite. (Portrait photograph, courtesy of the Armed Forces Institute of Pathology, photograph negative No. 62-1590.)

ful. In 1910, at the Army Medical School, Maj. (later Brig. Gen.) Carl R. Darnall, MC (1867-1941) (fig. 33), devised the enormously useful system for the chlorination of drinking water supplies by treatment with anhydrous chlorine gas (170).

The Lyster bag.-In 1913, Maj. (later Col.) William J. L. Lyster, MC (1869-1947) (fig. 34), invented the "Lyster bag" for the chlorination of drinking water in the field and in camps (and also in civilian locations) by the addition of calcium hypochlorite to the water (171).

After it was noted that mental disorders were occurring



FIGURE 35.- Edward Lyman Munson (1868-1947). As President of the Army Shoe Board at Fort Leavenworth, Kansas, he guided the development of an improved shoe, called "the Munson last." This was an accomplishment of preventive medicine which contributed to the comfort of the soldier and increased the mobility of infantry. (Portrait photograph, courtesy of the National Library of Medicine, photograph negative No. 640.)

among soldiers during maneuvers along the Mexican border in 1911 at a rate higher than the civilian rate, increased attention was given to the possibilities of preventive neuropsychiatry. This phase of military preventive medicine took a definite upturn in this period.

The Army Shoe Board and the Munson last.-During the same period, the other end of the soldier's body-his feet-received careful and scientific study, with special reference



to footwear. Before 1912, a soldier was issued one pair of shoes which usually did not fit, cramping the toes, deforming the foot, and causing incapacity particularly on marches. To investigate this and reform the conditions, the able and thoughtful Army Shoe Board, formed at Fort Leavenworth, Kansas, in 1908, and directed by Col. (later Brig. Gen.) Edward Lyman Munson, MC (1868-1947) (fig. 35), issued its revolutionizing report in 1912. A new pattern of shoe, made on the Munson last was described, and methods for measuring and fitting were outlined. This shoe and related procedures were officially adopted (172). This humble measure of comfort was a definite contribution by preventive medicine to the mobility of infantry, and as will be seen, socks and shoes had a determining influence on some phases of World War II.

Books on preventive medicine produced.-This period was also notable for the production of treatises on military hygiene and manuals of preventive medicine. After 1900, military sanitary officers published more books on these subjects than had appeared in many years previous to the bacteriological era. Particularly worthwhile for their times, and now as historical depictions of "the state of the art" on the eve of World War I, were the volumes by Munson, Ashburn, Havard, and Vedder (173).

At this stage in the evolution of preventive medicine in the United States Army, there is discernible a preoccupation with massive procedures. With the individual in mind as a beneficiary, but with the Army in mind as the composite functioning organization to be preserved, measures were taken to make the mass invulnerable to disease germs by strengthening the internal biological mechanisms of the individual and by erecting external fortifications to noxious agents. Among the examples of both types of measures are vaccination of the thousands, detection and control of carriers, specific and nonspecific attacks on insect vectors, proper shoes for multitudes of feet, purification or chlorination of drinking water for all, and voluminous sewage disposal systems and plants.