Research Finds AIDS Virus Origin to 100 Years Ago

A research team has come up with a suggestion that the HIV pandemic may have started 100 years ago, between 1884 and 1924, over 30 years before previous estimate. An international team of scientists has reached this claim after investigating African human tissue samples preserved for nearly 50 years. The finding was published in the October 2 issue of the journal Nature.

The research team was lead by Dr. Michael Worobey, an assistant professor of ecology and evolution biology at the University of Arizona in Tucson, together with colleagues from research centers in Australia, Belgium, France, Democratic Republic of the Congo, Denmark, and the United States.

Worobey’s team suggested that the beginnings of HIV/ AIDS pandemic was caused by the growing urbanization of colonial Africa during the beginning of the 20th century, together with the growth of cities and a rise in high risk behaviors. It has also created the conditions that allowed the most pervasive strain of HIV, the HIV-1 group M, to spread among humans.

Worobey and colleagues spent eight years screening tissue samples until they discovered a genetic sequence of HIV-1 group M coming from a lymph-node tissue biopsy from a woman who lived in present-day Kinshasa in the Democratic Republic of the Congo. Meanwhile, the oldest genetic fragment of HIV-1 group M came from a 1959 blood sample from a male resident of Kinshasa.

The researchers then created a range of possible family trees for the HIV-1 group M using their samples as well as other known HIV-1 genetic sequences. From there, they made time estimates of when the strains diverged from their ancestors. After projecting backwards, the researchers estimated when the pandemic began, which they put at around the beginning of the 20th century.