The observed epidemiology of SARS-CoV-2 in sub-Saharan Africa has varied greatly from that in Europe and the United States, with much lower reported incidence. Population-based studies are needed to estimate true cumulative incidence of SARS-CoV-2 to inform public health interventions. This study estimated SARS-CoV-2 seroprevalence in four selected states in Nigeria in October 2020. We implemented a two-stage cluster sample household survey in four Nigerian states (Enugu, Gombe, Lagos, and Nasarawa) to estimate age-stratified prevalence of SARS-CoV-2 antibodies. All individuals in sampled households were eligible for interview, blood draw, and nasal/oropharyngeal swab collection. We additionally tested participants for current/recent malaria infection. Seroprevalence estimates were calculated accounting for the complex survey design. Across all four states, 10,629 (96·5%) of 11,015 interviewed individuals provided blood samples. The seroprevalence of SARS-CoV-2 antibodies was 25·2% (95% CI 21·8–28·6) in Enugu State, 9·3% (95% CI 7·0–11·5) in Gombe State, 23·3% (95% CI 20·5–26·4) in Lagos State, and 18·0% (95% CI 14·4–21·6) in Nasarawa State. Prevalence of current/recent malaria infection ranged from 2·8% in Lagos to 45·8% in Gombe and was not significantly related to SARS-CoV-2 seroprevalence. The prevalence of active SARS-CoV-2 infection in the four states during the survey period was 0·2% (95% CI 0·1–0·4). Approximately eight months after the first reported COVID-19 case in Nigeria, seroprevalence indicated infection levels 194 times higher than the 24,198 officially reported COVID-19 cases across the four states; however, most of the population remained susceptible to COVID-19 in October 2020.

Objective: Viral load suppression (VLS) is critical in reducing morbidity and mortality associated with HIV as well as minimizing the likelihood of HIV transmission to uninfected persons. The objective of this study was to identify factors associated with VLS among people living with HIV (PLWH) on antiretroviral (ARV) therapy to inform HIV programme strategies in Nigeria.Methods: Adult participants, aged 15-64 years, from the 2018 Nigeria HIV/AIDS Indicator and Impact Survey (NAIIS), who self-reported to be a PLWH or had detectable ARVs, were analysed to examine factors associated with VLS defined as HIV RNA <1000 copies/mL. NAIIS measured HIV prevalence, viral load, ARV and hepatitis B in PLWH. Logistic regression models were used and reported weighted prevalence. Results: Of 1322 participants, 949 (68.25%) were women and 1287 (96.82%) had detectable ARVs. The median age was 39.31 [interquartile range (IQR): 31.47-47.63] years. Prevalence of VLS was 80.88%. Compared with participants with detectable ARVs, those with undetectable ARVs in their blood specimens had lower odds of VLS [adjusted odds ratio (aOR) = 0.24, 95% confidence interval (CI): 0.08-0.64). Coinfection with hepatitis B and nonnucleoside reverse transcriptase inhibitor metabolites were also associated with lower odds of VLS. Older people (45-54 vs 15-24 years) had increased odds of VLS (aOR = 2.81, 95% CI: 1.14-6.90). Conclusion: Young people and those with undetectable ARVs had lower odds of virological suppression. Targeted interventions focusing on young people and adherence to medication are needed to achieve the UNAIDS 95-95-95 goals for HIV epidemic control.