In the summer of 1981, when the first cases of AIDS were reported from New York City, Los Angeles, and San Francisco, many assumed that this was a disease confined to gay men in the United States. However, soon thereafter, cases were reported from other developed countries, particularly European countries, and especially Belgium and France. But what gradually became apparent was that AIDS was really predominantly a disease of the developing world. The evidence of this was hidden in plain sight; we just did not appreciate it at the time.
Among the Europeans who were seeing AIDS patients was Peter Piot, a Belgian national who had studied infectious diseases at the University of Washington in Seattle and was now back at his home base at the University of Antwerp. Peter was also seeing Zairian nationals who had come to Belgium for medical care or were European nationals who had traveled to or lived in sub-Saharan countries including Zaire, now the Democratic Republic of the Congo. What was fascinating to Peter and those of us closely following the evolution of the AIDS epidemic was that many of these patients with an African connection were heterosexual. They had a disease identical to what we were seeing among gay men. Few people believed that this was AIDS since AIDS was not supposed to happen via heterosexual sex.
At about the same time Piot was noticing these cases in Belgium, the CDC reported in 1982 that a disproportionate number of Haitians in the United States, many of whom were heterosexual, were being diagnosed with AIDS. As a result of this information, Dr. Richard Krause, my predecessor as director of NIAID, visited Port-au-Prince, Haiti, with a team of NIAID physician-scientists including two members of my lab, Cliff Lane and Dr. Tom Quinn, who had come from an infectious diseases fellowship at the University of Washington in Seattle. They wanted to determine if the disease was present in Haiti and how it was being transmitted. It soon became clear to them that many Haitians were afflicted with AIDS and that it affected both men and women, suggesting that heterosexual transmission might be common. They also became aware that from a historical perspective many Haitians had lived in Zaire over the prior ten years as a result of a bilateral arrangement between the governments of Haiti and Zaire. Many of these Haitians returned home in the early 1970s; some became ill with AIDS-like illnesses several years later.
We needed to know what was going on in southern Africa. Piot wanted to investigate the possibility that AIDS was present in a major way in Zaire. In 1984 with support from NIAID, a multi-institutional collaboration among the University of Antwerp, NIAID, and the CDC was established. The project was called Projet SIDA (syndrome d’immunodéficience acquise), and it launched a substantial epidemiological, clinical, and laboratory investigation. Within weeks it became clear to the group that heterosexual transmission of AIDS was occurring widely in Zaire and the epidemic likely had started in the early 1970s. Unlike the patterns in the United States, the male-to-female ratio of AIDS was one to one.
The investigations continued until 1992, when unrest in Zaire jeopardized the safety of our investigators. This forced me to evacuate my team by air out of Kinshasa. However, an extraordinary amount of important epidemiological data were collected from the project that, together with studies from other sub-Saharan countries, established definitively that HIV/AIDS was predominantly a disease of heterosexual transmission concentrated in the developing world, particularly in sub-Saharan Africa. Today more than 90 percent of cases are in low- and middle-income countries, and more than 65 percent are in sub-Saharan Africa.
In Zaire, percentages of infection among pregnant women and female sex workers were so high as to be almost unbelievable. For example, in some prenatal clinics, at least 20 to 40 percent of the pregnant women were infected. In certain locations, more than 80 percent of female sex workers were infected. In one study, from 1 to 18 percent of otherwise healthy blood donors were infected. In certain countries, the percentage of individuals fifteen to forty-nine years old who were infected was in double figures.
Beyond Zaire, by the time accurate surveillance was available in many sub-Saharan countries, the numbers of individuals who were infected were staggering. In Zimbabwe, Botswana, Swaziland (now Eswatini), and Lesotho, the percentage of people in the general population who were infected was about 20 percent. In South Africa that number was 11 percent in 1998, and it rose to 15.8 percent by 2005. Tom Quinn, who was the chief of the International HIV/Sexually Transmitted Diseases Section of my lab and who spent considerable time in Africa, reported back to me regularly with these astounding numbers months before he and his colleagues published them in the medical literature. This was horrible beyond our imagination. To make matters worse, even the modestly effective single-drug and two-drug anti-HIV treatments that were available in the developed world in the late 1980s and early 1990s were completely out of reach to most people with AIDS in southern Africa. Even simple treatments such as antibiotics and antivirals for the secondary opportunistic infections were mostly unavailable for many of these patients.
Relief was nowhere in sight.