SARS-CoV-2 seroprevalence in pregnant women during the first three COVID-19 waves in The Gambia

OBJECTIVES: SARS-CoV-2 transmission in Sub-Saharan Africa has probably been underestimated. Population-based seroprevalence studies are needed to determine the extent of transmission in the continent. METHODS: Blood samples from a cohort of Gambian pregnant women were tested for SARS-CoV-2 total receptor binding domain (RBD) IgM/IgG before (Pre-pandemic: October-December 2019), and during the pandemic (Pre-wave1: February-June 2020; Post-wave1: October-December 2020, Post-wave2: May-June 2021; and Post-wave3: October-December 2021). Samples reactive for SARS-CoV-2 total RBD IgM/IgG were tested in specific S1- and nucleocapsid (NCP) IgG assays. RESULTS: SARS-CoV-2 total RBD IgM/IgG seroprevalence was 0.9% 95%CI (0.2, 4.9) in Pre-pandemic; 4.1% (1.4, 11.4) in Pre-wave1; 31.1% (25.2, 37.7) in Post-wave1; 62.5% (55.8, 68.8) in Post-wave2 and 90.0% (85.1, 93.5) in Post-wave3. S-protein IgG and NCP-protein IgG seroprevalence also increased at each Post-wave period. Although S-protein IgG and NCP-protein IgG seroprevalence was similar at Post-wave1, S-protein IgG seroprevalence was higher at Post-wave2 and Post-wave3, [prevalence difference (PD) 13.5 (0.1, 26.8) and prevalence ratio (PR) 1.5 (1.0, 2.3) in Post-wave2; and 22.9 (9.2, 36.6) and 1.4 (1.1, 1.8) in Post-wave3 respectively, p<0.001]. CONCLUSION: SARS-CoV-2 transmission in The Gambia during the first three COVID-19 waves was high, differing significantly from official numbers of COVID-19 cases reported. Our findings are important for policy makers in managing the near-endemic COVID-19

SARS-CoV-2 Seroprevalence in The Gambia dataset

A quantitative dataset containing information on COVID seroprevalence in pregnant women, based upon an analysis of samples collected from 803 women between October 2019 – March 2022 in Farafenni, North Bank Region of The Gambia. This is a sub-set of women in the PRECISE Study where pregnant women were recruited to the cohort and followed up during their pregnancy