Lots of people are talking about this latest paper on HIV. It is an “open access” paper in the PNAS, and you can get it here.Human immunodeficiency virus (HIV) is a retrovirus that can cause AIDS (acquired immunodeficiency syndrome). It is a member of a larger group of viruses (the Smian immunodeficiency viruses) which are generally thought to be of African origin. There are two types of HIV (HIV-1, and HIV-2), with HIV-1 being the more virulent and, in human populations, most widespread.There are several theories as to the origin of HIV. When I was in Zaire in the mid 1980s, people in the cities were insisting that several Zairois had been brought to the US and infected with “Sida” (AIDS) and sent back t Zaire unaware of their condition to spread the disease. It has been suggested that HIV was accidentally included in polio vaccine. These and other ideas are highly unlikely, as it turns out. Continue reading HIV: Congo to Haiti to Pandemic →