The biology and epidemiology of HIV-2.

Abstract

HIV-1 was identified before HIV-2. Much of the virologic characterization of both types of HIV is therefore based upon research on HIV-1. HIV-1 and HIV-2 are closely related human lentiviruses, with much of the virus-cell interactions, genetic structure, and overall morphology of HIV-2 resembling those of HIV-1. The two viruses are, however, distinct viral types rather than different viral strains or variants. Seroepidemiologic studies have found significant rates of HIV-2 infection in Africa, mainly in West Africa. The virus has also been described in Angola, Mozambique, Tanzania, and sporadically in other African regions. There are only extremely low HIV-2 infection rates in the US and Europe. This paper discusses the cell tropism and viral receptors of HIV-2, formation and organization of the provirus, the regulation of proviral transcription, viral gene products, virion assembly and ultrastructure, epidemiology, and clinical outcome. The rate of progression from seroconversion to US Centers for Disease Control stage IV disease appears to be 3-4 times faster in the case of infection with HIV-1 compared to infection with HIV-2. - See more at: http://www.popline.org/node/302832#sthash.oUZLV6Qs.dpuf