Timing the Ancestor of the HIV-1 Pandemic Strains [B Korber, et al. Science 2000;288:1789]: The authors analyze HIV-1 sequences to estimate the timing of the ancestral sequence of the main group of HIV-1 using supercomputers and assuming a constant rate of mutation. This is a collaborative project involving investigators at Los Alamos, Manchester, Birmingham, Alabama, and Northwestern. The analysis places the origin of HIV in the early 1930's with a 95% confidence interval of 1915 to 1941.
Comment: This paper is of topical interest because some investigators have recently suggested that the AIDS epidemic may have resulted from contaminated polio vaccine, which was used in the 1950's. The observations here would seriously challenge that hypothesis. The accompanying review of this report by David Hillis from the University of Texas addresses obvious questions regarding the HIV epidemic in humans. It appears that the virus, if present in the 1930's, spread slowly so that by 1950 there were 10 or fewer HIV-1 M-group lineages. The explosion of the epidemic in the 1950's and 1960's occurred at the time of the end of colonial rule in Africa, multiple civil wars, widespread vaccination programs with reuse of needles, growth of African cities, the sexual revolution, and increased international travel. The addition of the average 10-year interval from infection to clinical expression provides the explanation for the initial recognition of AIDS in the 1970's in the U.S. and Europe. posted 6/29/2000