Puerto Rico
While working for the Rockefeller Institute, Rhoads was assigned to a William B. Castle's anemia research commission at Presbyterian Hospital in San Juan, Puerto Rico, in 1931 as part of the Rockefeller Foundation's sanitary commission there (later the International Health Board). Castle's research interest was pernicious iron deficiency anemia, specifically that caused by the parasitic hookworm, which was endemic, as well as the related condition of tropical sprue. As recently as 2010, Nieto Editores reported that these conditions were a cause of high mortality in Puerto Ricans.
Rhoads was sent to assist Castle and also perform another similar study in Cidra in conjunction with the School of Tropical Medicine, which had had an earlier Anemia Commission that did similar work. He also collected polio samples for Flexner. Author Susan E. Lederer, chair of the Medical History and Bio-ethics department of the University of Wisconsin, notes that letters from this time include some where Rhoads refers to his patients as animals: "The exciting experiment now is the attempt to cause experimental sprue in humans. If they don’t develop something they certainly have the constitutions of oxen," he said in one of his letters. Rhoads, she adds, sought to experimentally induce the conditions he was studying in his patients rather than simply treat them.
Read more about this topic: Cornelius P. Rhoads