The PRECISE PeriCOVID Africa Consortium contributed important evidence on the seroepidemiology of COVID-19 infection during pregnancy and helped define the impact of COVID-19 disease among pregnant women in The Gambia, Kenya, and Mozambique.

Research teams in each country analysed stored PRECISE blood samples collected from pregnant women living in both urban and rural communities. These samples were tested for antibodies against SARS-CoV-2 to track the evolution of the pandemic and assess the extent of infection within the population.

Across all three countries, COVID-19 seroprevalence increased substantially over the study period and closely mirrored successive waves of infection. The proportion of women with detectable antibodies rose rapidly, reaching its highest levels between late 2021 and early 2022, when the Omicron variant was predominant. Peak seroprevalence estimates were 89.7% in Kenya, 85.1% in The Gambia, and 79.9% in Mozambique.

These findings indicate that SARS-CoV-2 infection was far more widespread than suggested by official surveillance reports. The discrepancy highlights the value of seroprevalence studies in capturing the true burden of infectious diseases such as COVID-19, particularly in settings where routine case detection may underestimate transmission.

Infographics: Maura Malanga

Related Publications:

Janha R, Bah A, Jah H, Touray F, Idris Y, Keita S, Gaye Y, Jallow S, Faye-Joof T, Njie B, Craik R, Mohammed N, von Dadelszen P, D’Alessandro U, Roca A, PRECISE Network. SARS-CoV-2 seroprevalence in pregnant women during the first three COVID-19 waves in The Gambia. International Journal of Infectious Diseases. 2023.

Koech A, Omuse G, Mugo AG, Mwaniki IG, Mutunga JM, Mukhanya MW, Wanje O, Mwashigadi GM, Katana GG, Craik R, von Dadelszen P, Le Doare K, Temmerman M, periCOVID-Africa, PRECISE Network. SARS-CoV-2 seroprevalence in pregnant women in Kilifi, Kenya from March 2020 to March 2022. Frontiers in Public Health. 2023.

Sevene E, Maculuve S, Tchavana C, Valá A, Quimice L, Macuacua S, Carrilho C, Gonzalez R, Nhampossa T, Menendez C, Craik R, Hookham L, Le Doare K, von Dadelszen P, periCOVID-Africa, PRECISE Network. SARS-CoV-2 seroprevalence among pregnant women during the first three waves of the COVID-19 pandemic in southern Mozambique . BMC Pregnancy and Childbirth. 2026.

Koech A, Wanje O, Mwashigadi G, Katana G, Mdindi R, Mwangome P, Craik R, Vidler M, Kinshella M-LW, von Dadelszen P, Le Doare K, Temmerman M, The periCOVID-Africa Consortium and The PRECISE Network  “Now that the baby is out, I can be vaccinated”: a qualitative study on COVID-19 vaccine hesitancy in pregnant women in Kilifi, Kenya. 2026