A seroepidemiological study of human immunodeficiency virus infection in northeast Zaire.

To evaluate the incidence of human immunodeficiency virus type 2 infections in an endemic African area, we have studied 134 patients from Northeast Zaire. Sera were tested for HIV-1 and HIV-2 antibodies to asses cross-reactivity or a possible double infection. Sixty five (48.5%) serum samples were reactive for HIV-1 and six (4.5%) for HIV-2 using specific Western blots. The enzyme immunoassays used to detect HIV-2 showed cross-reactivity with HIV-1 in 17 samples (16.5%). Tests based upon synthetic peptides corresponding to specific from human immunodeficiency viruses confirm their ability to discriminate antibodies directed against both viruses in 42/47 samples (89.4%); in 5/47 (10.6%) this test could not distinguish double infection from cross-reactivity. We suggest that the high number of sexual partners may be responsible for HIV transmission in our study group.