Science exonerates HIV's 'Patient 0'
Genetic reconstruction shows that the virus had been circulating for years in the US before the patient arrived.
For years, many have pinned HIV's US outbreak on one man: a flight attendant, nicknamed Patient 0, whose travels and sexual activity allegedly helped spread the virus quickly. However, there's now evidence to suggest that he was little more than a scapegoat. A team of American and British researchers has used genetic reconstruction to narrow down the American arrival of HIV to between 1970 and 1971, before Patient 0 was even having sex.
The scientists collected genetic samples from men infected during the late 1970s, and used RNA "jackhammering" to break apart the subjects' HIV genomes and recombine them into usable RNA sequences. From there, the team used known mutation rates to determine the sequences' common ancestor. Simply speaking, there was too much genetic diversity by the late 1970s for Patient 0 to be responsible -- HIV had to have arrived earlier.
The findings may well clear the attendant's name, but they should have a longer-lasting impact on our understanding of disease as a whole. The approach could help humanity understand how viruses spread and track their evolution. It won't directly contribute to possible cures, but following the development of a disease might help illustrate the seriousness of a given threat.
