Researchers trace first HIV case to 1959 in the Belgian Congo
February 3, 1998
Web posted at: 7:41 p.m. EST (0041 GMT)
CHICAGO (CNN) -- HIV probably originated in the late 1940s or early 1950s, and showed up in people 10 to 20 years earlier than has previously been estimated, researchers said Tuesday.
Dr. David Ho and colleagues from the Aaron Diamond AIDS Research Center in New York told a conference they traced the very first case of HIV infection to a man living in what was then the Belgian Congo in 1959.
The scientists found HIV in a blood sample taken from the man, who was a member of the Bantu tribe. The HIV in the sample looks like an ancestor of several subtypes of HIV now found around the world, suggesting that HIV "evolved from a single introduction into the African population in a time frame not long before 1959," the researchers said.
Leading AIDS researchers said Ho's new study, which is detailed in the latest edition of the journal "Nature," is a significant advance in the understanding of the disease and could prove important in developing an AIDS vaccine.
Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, said the new proof of HIV's earliest origins is important to scientists because it offers a much clearer picture of the evolution of the virus and a better way to predict its future evolution.
"The ancestral HIV-1... must have existed before 1959, probably only a few years before 1959," Toufu Zhu, who worked on the study, told the Fifth Conference on Retroviruses and Opportunistic Infections.
"The Big Bang seems to have occurred around, or just after, the Second World War," wrote Simon Wain-Hobson of the Pasteur Institute in Paris in a commentary in "Nature."
The 1959 victim, who lived in Leopoldville, now Kinshasa in the Democratic Republic of Congo, had first turned up at a clinic with symptoms resembling sickle cell anemia -- a hereditary blood disease that primarily affects Africans in which oddly-shaped red blood cells clump together, causing anemia, blood clotting and joint pain.
Doctors kept samples of the man's blood, and Ho's team analyzed it. Using well-established genetic dating methods, they determined that the virus could not have existed for many years before 1959.
Fauci said the research refutes various "conspiracy theories" that HIV is the by-product of Cold War germ warfare tests or poorly-conducted polio vaccine tests.
"This finding also refutes the suggestion that HIV-1 subtype B infection was responsible for AIDS-like syndromes beginning in the 1930s in various European populations," the researchers wrote in the report.
Scientists have yet to learn how HIV first infected humans. Many viruses come from animals, and HIV is believed to have come from monkeys -- but it is not clear how.
Another presentation at the conference on Tuesday gave a hint: Francois Simon and colleagues at the Bichat hospital in Paris and the Pasteur center in Cameroon found a strain of HIV that seemed to be halfway between the human and the ape versions of the virus.
Monkeys and chimpanzees get a disease known as Simian Immunodeficiency Syndrome, caused by a version of the HIV virus known as SIV. But chimps and monkeys infected with human HIV do not get AIDS in the same way as people, meaning the virus mutated at some point.
Simon's group analyzed the blood of a Cameroonian woman who died of AIDS in 1995. Her strain of the virus was unique and fell halfway between HIV and SIV genetically. It was identical to an odd strain taken from a chimpanzee.
The finding "strongly supports the hypothesis that HIV came from a simian virus," Simon told the conference.
However, little is known about the women, her family or history. It is not possible to say how she might have caught the virus from a chimpanzee.
"It's very difficult, but ... in Africa people eat monkeys," Simon said. Many scientists believe the virus spread to humans through infected ape or monkey meat.
Reuters contributed to this report.