Seroprevalence of Anti-SARS-CoV-2, IgM and IgG, and COVID-19 Vaccine Uptake in Nairobi, Kenya: A Cross-Sectional Study

Seroprevalence of anti-severe acute respiratory syndrome coronavirus 2 (anti-SARS-CoV-2) antibodies in the postvaccination period in Kenya remains to be elucidated. This study aimed to determine the seroprevalence of anti-SARS-CoV-2 IgM and IgG and evaluate vaccination uptake in Nairobi, Kenya. This was a cross-sectional study conducted in a university setting. Serum anti-SARS-CoV-2 IgM and IgG levels were assayed using enzyme-linked immunosorbent assays. Mann–Whitney U test was used for binary comparisons and Kruskal–Wallis Test for multigroup comparisons. Statistical significance was set at p < 0.05. A total of 189 participants were enrolled (median age, 21 years; female, 50.8%). The seroprevalence of anti-SARS-CoV-2 was 12.7% for IgM and 87.8% for IgG. Anti-SARS-CoV-2 IgG titers were higher among the vaccinated vs. non-vaccinated individuals (p < 0.001, U = 2817.5), females vs. males (p = 0.024, U = 3616), and those vaccinated < 6 months before the study vs. those vaccinated >1 year earlier (p = 0.002, H = 12.359). The vaccination hesitancy rate was 43.4% and the underlying reasons included mistrust (22.4%), health concerns (19.7%), and lack of information (18.4%). Despite the high seroprevalence of anti-SARS-CoV-2 IgG, the high vaccine hesitancy rate necessitates community engagement and education prior to vaccines roll out.