AIDS was recognized in humans in 1981 and a simian form was described in the years 1983 to 1985. However, beginning in the late 1960s, outbreaks of opportunistic infections of AIDS were seen in monkeys in the United States. This apparent syndrome went unrecognized at the time.

The article examines those early cases in monkeys and offers reasons why they did not result in earlier recognition of simian or human AIDS, including weaknesses in understanding disease mechanisms, absence of evidence of human retroviruses, and a climate of opinion that devalued investigation of infectious disease and immunologic origins of disease. The “epistemological obstacle” explains important elements of this history in that misconceptions blocked understanding of the dependent relationship among viral infection, immunodeficiency, and opportunistic diseases.

The researchers argue that “to make proper use of the available tools and data, continued vigilance, creative thinking, and interdisciplinary collaboration remain essential.” These will be critical to meeting the challenges of emerging infectious diseases, as evidenced by the recent Ebola and Zika outbreaks.” To meet these challenges, “cooperation and information exchange between veterinary and human disease researchers in a ‘One Health’ approach are also very important.”