Background: HIV-2 is a new retrovirus which may produce AIDS and has been mainly described in individuals from West Africa. More than 400 cases have been reported in France and Portugal while in Spain very few cases of HIV-2 infection have been reported with few studies having been made concerning the prevalence of the disease. This multicentric study analyzes the prevalence of HIV-2 infection in subjects of different risk groups in Spain and evaluates the diagnostic efficacy of different methodologies.
Methods: The presence of HIV-2 antibodies was analyzed in 902 serum samples of high risk individuals collected in 1990 from: 386 drug addicts, 246 not drug addict prostitutes, 184 West Africans and 86 homo/bisexual individuals. These samples were from Barcelona, Sevilla, and Malaga. The detection of antibodies was carried out by enzymatic immunoanalysis (EIA), Western blot (WB) and an enzymoimmuno-dot (EID) designed with synthetic peptides.
Results: Positive serology only for HIV-2 was detected in 7 samples from African immigrants. Two drug addicts presented double reactivity HIV-1/HIV-2 in all the tests suggesting double infection. No prostitutes or homo/bisexual males were identified with positive serology for HIV-2. Cross-reactivity between HIV-1 and HIV-2 was more frequently detected in WB than in EID. Greater discordance was found in the results obtained by EIA, WB, and EID in the West Africans than in the analysis of the samples of native subjects.
Conclusions: This study demonstrates that, for the time being, HIV-2 infection in Spain is rare although from among immigrants from endemic areas subjects with behavior to risk of transmission to the autochthonous population have been identified. The use of techniques designed with synthetic peptides may be of use to discriminate HIV-1 and HIV-2 infection in positive samples by enzymatic immunoanalysis (EIA) and Western blot which use a viral lysate as antigenic material.