Epidemiology and seroprevalence of human immunodeficiency virus type 2.

HIV-2 infection is detected sporadically mostly from the southern states of India. We did a retrospective analysis to find the seroprevalence of HIV-2 in and around Delhi. The study included all attendees of an integrated counseling and testing center (ICTC) from January 2004 to January 2009. As per NACO guidelines, samples showing positive results in three rapid tests were declared HIV-positive. Samples that were reactive for HIV-2 were further confirmed by Western blot assay. 8.8% (n = 1,938) of the clients were reactive for HIV-1, 0.03% (n = 6) were reactive for HIV-2 and 0.005% (n = 1) had HIV-1 and HIV-2 coinfection. Spouses of only 2 cases were tested, both resulting as nonreactive. History of travel or past stay to endemic states was present in 57% cases. The commonest risk factor revealed in them was sexual contact with commercial sex workers (86%). As such, seroprevalence of HIV-2 is very low but continued surveillance is needed for HIV-2 to understand the epidemiology and natural history of this complex human pathogen.