Prevalence of HIV and hepatitis B virus among pregnant women in Luanda (Angola): geospatial distribution and its association with socio-demographic and clinical-obstetric determinants.

Background: HIV and HBV infections remain responsible for high rate of morbidity and mortality in many African Countries, affecting women and newborns. This study aims to analyze the spatial pattern of HIV and HBV infections in pregnant women in Luanda, Angola, and the statistical association between HIV and HBV and socio-economic characteristics, hygiene, and health status.

Methods: Detection of anti-HIV antibodies (total anti-HIV-1, anti-HIV-2 and HIV-1 p24 antigen) and Hepatitis B antigens (HBsAg, HBeAg) and antibodies (anti-HBc Total II, HBc IgM, Anti-HBsT II) was performed by Enzyme Linked Fluorescent Assay (ELFA) in serum samples of 878 pregnant women attended at the Lucrecia Paim Maternity Hospital (LPMH). Data were collected by questionnaire after written consent, and spatial distribution was assessed through a Kernel Density Function. The potential risk factors associated with HIV HBV infection were evaluated using bivariate and multivariate binomial logistic regression analysis.

Results: Anti-HIV antibodies were positive in 118 samples (13.4%) and HBV infection were positive in 226 (25.7%). The seroprevalence of HIV/HBV coinfection was of 6.3%. The results showed that the seroprevalence of HBV was similar in most municipalities: 25.8% in Belas; 26.6% in Viana; 27.6% in Luanda; 19.2% in Cacuaco; and 15.6% Cazenga. For HIV, the seroprevalence was also close ranges among the municipalities: 10.0% in Belas; 14.5% in Viana 14.9% in Luanda and 12.5% in Cazenga. However, the seroprevalence in municipality of in Cacuaco was lower (5.8%) and bivariate and multivariate analysis showed a lower risk for HIV in this area (OR 0.348, CI 0.083-0.986; OR 0.359, CI 0.085-1.021). The multivariate analysis had also showed a significant increased risk for HIV in women with 2 or 3 births (OR 1.860, CI 1.054-3.372).

Conclusions: Our results underlined the need to improve the screening and clinical follow-up of HIV and HBV in Angola, as well the educational campaigns to prevent not only the morbidity and mortality associated with these diseases, but also their transmission, mainly in women in reproductive age and pregnant, encouraging the pre-natal consultations in order to avoid mother-to-child transmission.