Seroprevalence of HIV-1, HIV-2, and HIV-1 group O in Nigeria : Evidence for a growing increase of HIV infection

To obtain current data on HIV infection in Nigeria by population group a seroanalysis of 2300 samples from 5 states (Lagos Cross River Borno Kano and Jugawa) was conducted during March-May 1996. The sample included commercial sex workers pregnant women tuberculosis patients blood donors patients with sexually transmitted diseases (STDs) patients with skin diseases male clients of commercial sex workers outpatients suspected to have AIDS truck drivers and community residents. Overall HIV prevalence was 40.7%. With the exception of pregnant women (1.7%) HIV prevalence was high in all subgroups: 60.6% in commercial sex workers 21.2% in STD patients 16.2% in tuberculosis patients and 16.0% in rural areas of Kano state. The majority of HIV-positive women were 21-30 years of age while HIV-infected men were primarily over 40 years of age. Compared with data from national seroprevalence studies conducted during 1991-92 and 1993-94 this study confirms a substantial recent increase in HIV infection in Nigeria. Of the 330 antibody-positive specimens HIV-1 was the predominant infection in 315; there were 3 cases of HIV-2 and 12 cases involving dual HIV-1/2 infection. Only 1 serum sample was positive for HIV-1 group O antibodies. The high HIV prevalence detected among commercial sex workers indicates the potential for rapid diffusion of HIV to the general population.