A brief report made by Sawyer regarding Yellow Fever activities in Brazil.

A brief report made by Sawyer regarding Yellow Fever activities in Brazil.

Dr. Downs' diary entries take the form of monthly reports regarding the entomological, epidemiological, laboratory, and zoological activities of the Trinidad Regional Virus Laboratory for this entire period. The reports include extensive data and observations on experiments, animals, and patients related to the isolation of viral agents, and discuss the progress of supplementary projects such as the establishment of an insectary and the collection of animal skins. Strains of mayaro, dengue, ilheus, yellow fever, St. Louis, and malaria are the primary viruses being isolated and studied at the TRVL. Surveys and preliminary data on Grenada and British Guiana are included as supplements to two of the monthly reports.

Dr. Downs and his personnel at the Trinidad Regional Virus Laboratory continue to survey the distribution of viral agents and vectors—both insect and mammal—on the island of Trinidad. Human, animal, and mosquito blood specimens are collected in order to identify viral agents and mice are inoculated with the viral agents so that strains may be isolated. In order to acquire human blood specimens from patients with unidentified fevers, Dr. Downs begins to work part-time at the Sangre Grande clinic, exchanging his services as a practitioner for blood specimens. In this manner, a variety of viral strains are isolated including strains of the Ilheus, Dengue and Yellow Fever virus. Further analysis of Yellow Fever consists of a Yellow Fever Immunization Study and medical analysis of patients before and after receiving the Yellow Fever vaccination. All entomological, epidemiological, and laboratory activities from July to December are described in detail in a fortnightly report.

With the Trinidad Regional Virus Laboratory in full operation, Dr. Downs and his team of laboratory technicians and scientists begin a country-wide campaign to collect blood specimens of animals and humans afflicted with undiagnosed fevers and encephalitis. Concentrating on medical—and not clinical—science, Dr. Downs and his team inoculate animals with viral strains (obtained from infected persons) in hopes of identifying the viral agents causing the undiagnosed maladies. Given the ubiquity of encephalitis in this particular time period, Dr. Downs begins to suspect that the country may be on the verge of a Yellow Fever epidemic. By investigating the abnormal dying-off of indigenous monkeys and the loss of five human victims, Dr. Downs and his team successfully isolate strains of Yellow Fever and alert the Trinidadian authorities that it has reemerged. A government vaccination campaign is launched and other South and Central American authorities are warned as well. A conference in Washington is organized in order to address the threat of Yellow Fever in the Americas and in the United States. Dr. Downs is an attendee and speaker at the conference.