Use of Replacement Blood Donors to Study the Epidemiology of Major Blood-borne Viruses in the General Population of Maputo, Mozambique

The seroprevalence rates of human immunodeficiency virus (HIV), human T-cell leukemia/lymphoma virus (HTLV), hepatitis B virus (HBV), hepatitis D virus (HDV), and hepatitis C virus (HCV) in Mozambique are poorly documented. The epidemiology of these infections was studied in the Maputo region. All donors attending the blood bank during the study period were interviewed and underwent serological and molecular tests for markers of virus exposure. Thus, 1,578 consecutive replacement blood donors were investigated, as they undergo no selection (other than their relation with a patient needing a transfusion), and may thus provide reliable estimates of the prevalence rates in the general population. The age-standardized prevalence rates among 15- to 49-year-old men and women were, respectively, 12.3 and 15.4% for HIV and 0.9 and 1.2% for HTLV. Low educational status (P = 0.014) and tattooing/scarification (P = 0.023) were predictive of HIV infection in multivariate analysis. The age-adjusted prevalence rates of markers of hepatotropic virus among men and women were, respectively, 10.6 and 4.5% for hepatitis B surface antigen (HBsAg), 1.2 and 1.0% for anti-HCV, and 0 and 0% for anti-HDV. Two percent of donors had viral co-infections, involving most frequently the combination of HIV and HBsAg +. A significant association was found between anti-HIV and anti-HBc (P = 0.012). HBsAg was associated with the place of birth (P = 0.011) and a history of transfusion (P = 0.069). Smokers had higher seroprevalence rates than nonsmokers for HIV (P < 0.0001) and HBsAg (P = 0.045). Genotype A was the most frequent HBV genotype (86.3%) followed by E and D. HCV genotypes were 1a, 1b, 3a, and 5a. These results show that HBV vaccination and HIV-preventive measures need to be reinforced in Mozambique.