Despite high seroprevalence rates in some parts of Africa, there is notable variation in prevalence between population subgroups. To document changes and trends in HIV seroprevalence in northeastern Zaire, 1989 to 1992 blood donor data were reviewed. Overall, 2453 donors were tested with seropositivity varying from 2.8% in 1989 to 6.9% in 1992. The increase in seropositivity was significant for men (2.5 to 5.8%, P = 0.017) and for people residing in rural areas (2.0 to 6.1%, P = 0.0008) but not for women (5.4 to 8.6%, P = 0.15) nor for urban individuals (10.5 to 8.6%, P = 0.55). These findings suggest that: 1) HIV infection is spreading in previously less-affected population subgroups rather than increasing widely in the entire population, 2) the HIV epidemic could be reaching a plateau or endemic phase in northeastern Zaire, and, 3) continued blood donor screening and wise transfusion practices are needed.
PIP: During March 1989-December 1992, laboratory personnel at the Evangelical Medical Center in Nyankunde, Zaire, used HIVCHECK (DuPont) to screen 2453 blood donations for HIV. The overall HIV prevalence rate was 5.6% (138 HIV-positive blood donors). The overall trend toward increasing seroprevalence was significant (p = 0.0052). When the researchers divided the data into the initial 13 months of the study and the final 12 months, the overall HIV seropositivity increased significantly (3.7-6.9%; p = 0.009). The subgroups in which it increased significantly were men (2.5-5.8%; p = 0.017) and persons living in rural areas (2-6.1%; p = 0.0008). Yet, HIV seropositivity remained more prevalent among women and urban dwellers (8.6% for both groups). It actually decreased during the study period among urban dwellers (10.5-8.6%). In February 1993, health workers began to inform blood donors that their blood would be screened for HIV. Prior to that, blood donors were not informed of their HIV status. In 1993, the HIV seroprevalence rate was 5% for potential blood donors, 5.5% for urban dwellers, 4.7% for rural dwellers, 6.4% for women, and 4% for men. These findings suggest that HIV infection is expanding to previously less-affected population groups instead of rising in the whole population. They also indicate that the HIV epidemic has stabilized and thus has entered an endemic phase in this area of Zaire. Nevertheless, health professionals must continue to screen blood donations and to use careful, selective transfusion practices.