SARS-CoV-2 antibody seroprevalence and associated risk factors in an urban district in Cameroon
Kenechukwu Obumneme Samuel Nwosu, Joseph Fokam, Franck Wanda, Lucien Mama, Erol Orel, Nicolas Ray, Jeanine Meke, Armel Tassegning, Désiré Takou, Eric Mimbe, Béat Stoll, Josselin Guillebert, Éric Comte, Olivia Keiser, Laura Ciaffi
Abstract
The extent of SARS-CoV-2 circulation in many African countries remains unclear, underlining the need for antibody sero-surveys to assess the cumulative attack rate. Here, we present the results of a cross-sectional sero-survey of a random sample of residents of a health district in Yaounde, Cameroon, conducted from October 14 to November 26, 2020. Among the 971 participants, the test-adjusted seroprevalence of anti-SARS-CoV-2 IgG antibodies was 29·2% (95% CI 24·3-34·1). This is about 322 times greater than the 0.09% nationwide attack rate implied by COVID-19 case counts at the time. Men, obese individuals and those living in large households were significantly more likely to be seropositive, and the majority (64·2% [58·7-69·4]) of seropositive individuals reported no symptoms. Despite the high seroprevalence, most of the population had not been infected with SARS-CoV-2, highlighting the importance of continued measures to control viral spread and quick vaccine deployment to protect the vulnerable.