Seroprevalence and risk factors of STIs among rejected blood donors at the National Blood Transfusion Service in Angola

Abstract Background Sexually transmitted infections (STIs) are a global health concern. Blood donation centres employ comprehensive screening measures to identify donors with STIs, including HIV, HBV, HCV, and syphilis ensuring the safety of the donated blood and protecting the recipients. Herein, we investigated the seroprevalence of STIs and risk factors related to multiple infections among rejected blood donors at the National Blood Transfusion Service (NBTS) in Angola. Methods This was a cross-sectional study conducted with 1668 rejected blood donors serologically screened for anti-HBsAg, anti-HCV, anti-HIV, and anti-TP at the NBTS, located in Luanda, the capital city of Angola, between March 2022 to July 2023. Results Overall, HIV (11.2%), HBsAg (71.7%), HCV (9.30%), and Syphilis (8.80%) were detected. The multiple infection rate was 2.30%, from these, HIV/HBV (1.10%), HIV/HCV (0.60%), HIV/Syphilis (1.20%), HBV/HCV (8.0%), HBV/Syphilis (5.50%), and HCV/Syphilis (1.80%) coinfections, were detected. HIV and syphilis were related to age groups (p < 0.05). HBV was related to age group, areas of residence, occupation, and Rh factor (p < 0.05). HCV was related to areas of residence and educational level (p < 0.05). No relationship was observed between demographic characteristics with multiple infections (p > 0.05). Individuals aged over 40 years (OR: 2.48, p = 0.393), males (OR: 1.33, p = 0.639), non-urbanized regions (OR: 1.18, p = 0.594), low educational level (OR: 3.46, p = 0.222), and employed (OR: 1.34, p = 0.423), presented a higher likelihood of having multiple infections. Conclusions Our results demonstrate a high rate of circulation of STIs among young blood donation candidates in Luanda. However, the prevalence, particularly that of HBV, is one of the highest in the sub-Saharan African region, suggesting that priority should be given to strengthening donor screening and considering the possibility of including nucleic acid-based screening techniques.