HIV-2 INFECTION IN BISSAU, WEST-AFRICA, 1987-1989 - INCIDENCE, PREVALENCES, AND ROUTES OF TRANSMISSION

In a community study, the HIV-1 and HIV-2 antibody status of the inhab itants of 100 randomly chosen houses in Bissau, West Africa, were foll owed from 1987 to 1989. There was no HIV-1 infection alone, while the HIV-2 seroprevalence in adults was 8.9% (58 of 652) in 1987 and 10.1% (61 of 603) in 1989. HIV-2 seroprevalence in 15- to 39-year-olds was 6 .1% in 1987 and 11.3% in newcomers in 1989 [the Mantel-Haentzel weight ed relative risk (RR(MH)) = 1.86; 95% confidence interval (Cl): 1.07-3 .24]. Three hundred thirty adults who were HIV-2 seronegative in 1987 were reexamined in 1989; seven had seroconverted. Follow-up time was 7 00 person years, giving an incidence of HIV-2 infection of 1 per 100 p erson years. With a history of sexually transmitted disease (STD), the RR of seroconverting was 9.95 (2.31-42.80). Blood transfusions receiv ed since 1987 did not result in seroconversions. No case of vertical t ransmission of HIV-2 was seen. There was an excess mortality in those who were HIV-2 seropositive; however, it was statistically significant only for children (RR = 22.27; 95% CI: 6.92-71.70; p < 0.0001), not f or adults (RR = 2.16; 95% CI: 0.81-5.76; p = 0.23), when considering d eath from disease only.