Learning the Ropes: Hookworm Disease in South America, 1920-1927

Fred Soper's long career in international health began in Brazil, not with malaria or yellow fever, but with hookworm disease. Why Brazil? And why hookworm?

When he signed on with the Rockefeller Foundation, Soper became part of a more general early twentieth-century public health movement. For much of history, infectious and parasitic diseases (tuberculosis, malaria, influenza, typhus fever, and hookworm, to name a few) were among the leading causes of disability, poverty, and death. Global epidemics of cholera in 1832, 1849, and 1866 had led to the establishment of permanent public health boards in many European and American cities, and--often by trial and error--to measures to control it: better sanitation systems and clean water supplies, disinfection methods, and public education about the disease. During this same period, workers in military hospitals (notably Florence Nightingale) had successfully managed epidemic typhoid and typhus fever by improving cleanliness and ventilation and providing better sewage disposal. Meanwhile, researchers such as Louis Pasteur and Robert Koch had proved that many diseases were caused by microscopic organisms, and this idea--often called the "germ theory of disease"--slowly gained acceptance after 1870. By the late 1800s the causative microbes of many diseases had been identified, and public health departments could use this knowledge to track the spread of disease and take steps to contain it. As vaccines for some diseases became available, public health departments became more active in disease prevention, instead of just responding to epidemics.

Meanwhile, political and economic development in tropical regions was still hampered by insect-borne diseases and parasites. Americans, already aware of these problems in the southern U.S., encountered them anew when the 1898 Spanish-American War took U.S. troops to the Caribbean and the Philippines. Disease continued to be a major problem in these new areas of American influence; the Panama Canal construction under American direction (1904-1914) was seriously delayed at first by the incidence of malaria and yellow fever among the workers. As work progressed, North Americans worried that, while it facilitated trade, the canal would also help such diseases spread from Central and South America. At the same time, it was becoming clear that helping other countries improve public health could increase their prosperity and make them better trading partners.

The Rockefeller Foundation, Fred Soper's employer from 1920 to 1947, was established in 1913 to help promote a wide range of activities in science, arts, agriculture, civic education, and public health in the United States and abroad. Its public health work was intended in part to apply the medical knowledge generated at the Rockefeller Institute for Medical Research, founded in 1901. The Foundation's International Health Division (IHD) grew originally from the Rockefeller Sanitary Commission, which worked to reduce the prevalence and economic impact of hookworm disease in the southern U.S. from 1909 to 1914. This effort, combining treatment, sanitary improvements, public health education, and establishment of state and local public health administrative frameworks, was largely successful. Hookworm disease--which afflicted 90% of the population in some areas of the American south--was a good pilot project. Its nature, causes, effects, and cure were easily understood by average citizens, including politicians: these debilitating intestinal parasites were easy to see in the sufferers' feces, the treatment worked quickly and dramatically, and produced rapid improvements in health. Preventing hookworm disease was simple: treat all the town's residents, and have them build and use privies, so that the microscopic hookworm larvae could not contaminate the soil and enter the bare feet of new hosts. Once a community had learned these effective tactics by experience, its residents were prepared to accept and support projects to control diseases in which the causative agent was less obvious, and the route of infection indirect, such as malaria.

The IHD subsequently launched hookworm control programs around the world, selecting only countries whose governments were able and willing to work in partnership with it. (The ultimate goal was not just to control or eradicate disease, but to build or improve a permanent, functional public health apparatus that would carry on after IHD pulled out.) Brazil was a good candidate for such a cooperative project: it had a stable government and good diplomatic relations with the U.S., and some Brazilian cities already had sound public health organizations in place. The IHD staff was also impressed with the public health work done by Dr. Oswaldo Cruz in Rio de Janeiro on yellow fever and plague from 1903 to 1909.

Arriving in Brazil in early 1920, Soper assisted with a hookworm survey--learning Portuguese as he went--and then was assigned to establish four new county hookworm survey and treatment posts in the state of Pernambuco, Brazil. This assignment provided a hands-on education in public health administration. Each hookworm post was to be staffed by a physician, a chief inspector, microscopist, clerk, and 11 or 12 inspectors. Their first task was to educate the public (beginning with the chief community authorities) on the damage caused by hookworm disease, and how to prevent it with improved hygiene and sanitation. They then had to examine and treat as many of the hookworm sufferers as possible. Each county was divided into zones, and an inspector assigned to each zone, to number and register each house and then make a house-to-house census of all inhabitants. After a certain number were registered, the inspectors told them when exams and treatment would be available. (Treatment had to be scheduled in the early morning, as the treatment--chenopodium oil followed by a laxative--worked best on an empty stomach.) The hookworms expelled after the treatment then had to be collected, counted, and recorded, to assess the severity of the problem, and to identify which of two species of hookworms had been at work.

The projects were collaborative: the Rockefeller Foundation funded salaries, housing, food, and transportation (i.e., horses, mules, riding gear, and care for the animals). The county was to supply quarters for the post, including office, lab, storeroom, living quarters, dining area, and stable. Soper was responsible for negotiating with local authorities about these matters, and then for hiring, training, supervising, housing, provisioning, and paying staff. While the funding arrangement seemed straightforward, getting the promised share from the participating government was sometimes the primary challenge Soper faced as an administrator.

Personnel shortages presented another challenge. Not all local physicians were willing or able to work full-time with the IHD staff, and some communities had no physician at all. Soper improvised, and broke down survey and treatment tasks so that non-professionals could be trained to do them. In some cases, these trainees became better at the task than Soper himself, e.g. one microscopist could do accurate counts on more samples per day than any of the staff physicians.

Early on, Soper learned that consistent supervision and record-keeping were crucial to successful disease control. He had to be able to devise standard procedures for all parts of the control effort, and then find ways to identify and deal with the physicians and inspectors who failed to follow procedures, or attempted to fabricate field reports or expense reports to save themselves effort or money. Soper eventually devised a method for spotting defects in field staff performance by cross-comparison of field reports. In some cases, Soper encountered the opposite problem, as with the physician who was so zealous about giving hookworm treatments that he threatened some patients with his pistol! (Soper dismissed him after investigating, and the doctor protested by taking his story to the press.)

Finally, the years of hookworm work in Brazil and Paraguay developed Soper's diplomatic skills among local citizens, whose trust was needed if the surveys and treatments were to be effective. In some areas, the IHD found that men were hesitant to register for treatment, fearing that the surveys were a prelude to military conscription. In others, prospective patients were concerned that Rockefeller Foundation projects had evangelism as their hidden agenda (John D. Rockefeller was well-known for his generous endowments to Baptist organizations and institutions), or that hookworm campaigns aimed to create a market for the treatment oil, rumored (erroneously) to be a Standard Oil product.