Nature Communications (May 2024)
High SARS-CoV-2 incidence and asymptomatic fraction during Delta and Omicron BA.1 waves in The Gambia
- Sheikh Jarju,
- Rhys D. Wenlock,
- Madikoi Danso,
- Dawda Jobe,
- Ya Jankey Jagne,
- Alansana Darboe,
- Michelle Kumado,
- Yusupha Jallow,
- Mamlie Touray,
- Ebrima A. Ceesay,
- Hoja Gaye,
- Biran Gaye,
- Abdoulie Tunkara,
- Sheriff Kandeh,
- Marie Gomes,
- Ellen Lena Sylva,
- Fatoumata Toure,
- Hailey Hornsby,
- Benjamin B. Lindsey,
- Martin J. Nicklin,
- Jon R. Sayers,
- Abdul K. Sesay,
- Adam Kucharski,
- David Hodgson,
- Beate Kampmann,
- Thushan I. de Silva
Affiliations
- Sheikh Jarju
- Vaccines and Immunity Theme, Medical Research Council The Gambia at the London School of Hygiene and Tropical Medicine
- Rhys D. Wenlock
- Vaccines and Immunity Theme, Medical Research Council The Gambia at the London School of Hygiene and Tropical Medicine
- Madikoi Danso
- Vaccines and Immunity Theme, Medical Research Council The Gambia at the London School of Hygiene and Tropical Medicine
- Dawda Jobe
- Vaccines and Immunity Theme, Medical Research Council The Gambia at the London School of Hygiene and Tropical Medicine
- Ya Jankey Jagne
- Vaccines and Immunity Theme, Medical Research Council The Gambia at the London School of Hygiene and Tropical Medicine
- Alansana Darboe
- Vaccines and Immunity Theme, Medical Research Council The Gambia at the London School of Hygiene and Tropical Medicine
- Michelle Kumado
- Vaccines and Immunity Theme, Medical Research Council The Gambia at the London School of Hygiene and Tropical Medicine
- Yusupha Jallow
- Vaccines and Immunity Theme, Medical Research Council The Gambia at the London School of Hygiene and Tropical Medicine
- Mamlie Touray
- Vaccines and Immunity Theme, Medical Research Council The Gambia at the London School of Hygiene and Tropical Medicine
- Ebrima A. Ceesay
- Vaccines and Immunity Theme, Medical Research Council The Gambia at the London School of Hygiene and Tropical Medicine
- Hoja Gaye
- Vaccines and Immunity Theme, Medical Research Council The Gambia at the London School of Hygiene and Tropical Medicine
- Biran Gaye
- Vaccines and Immunity Theme, Medical Research Council The Gambia at the London School of Hygiene and Tropical Medicine
- Abdoulie Tunkara
- Vaccines and Immunity Theme, Medical Research Council The Gambia at the London School of Hygiene and Tropical Medicine
- Sheriff Kandeh
- Vaccines and Immunity Theme, Medical Research Council The Gambia at the London School of Hygiene and Tropical Medicine
- Marie Gomes
- Vaccines and Immunity Theme, Medical Research Council The Gambia at the London School of Hygiene and Tropical Medicine
- Ellen Lena Sylva
- Vaccines and Immunity Theme, Medical Research Council The Gambia at the London School of Hygiene and Tropical Medicine
- Fatoumata Toure
- Vaccines and Immunity Theme, Medical Research Council The Gambia at the London School of Hygiene and Tropical Medicine
- Hailey Hornsby
- Division of Clinical Medicine, School of Medicine and Population Health, The University of Sheffield
- Benjamin B. Lindsey
- Division of Clinical Medicine, School of Medicine and Population Health, The University of Sheffield
- Martin J. Nicklin
- Division of Clinical Medicine, School of Medicine and Population Health, The University of Sheffield
- Jon R. Sayers
- Division of Clinical Medicine, School of Medicine and Population Health, The University of Sheffield
- Abdul K. Sesay
- Vaccines and Immunity Theme, Medical Research Council The Gambia at the London School of Hygiene and Tropical Medicine
- Adam Kucharski
- Centre for Mathematical Modelling of Infectious Diseases, London School of Hygiene and Tropical Medicine
- David Hodgson
- Centre for Mathematical Modelling of Infectious Diseases, London School of Hygiene and Tropical Medicine
- Beate Kampmann
- Vaccines and Immunity Theme, Medical Research Council The Gambia at the London School of Hygiene and Tropical Medicine
- Thushan I. de Silva
- Vaccines and Immunity Theme, Medical Research Council The Gambia at the London School of Hygiene and Tropical Medicine
- DOI
- https://doi.org/10.1038/s41467-024-48098-3
- Journal volume & issue
-
Vol. 15,
no. 1
pp. 1 – 10
Abstract
Abstract Little is known about SARS-CoV-2 infection risk in African countries with high levels of infection-driven immunity and low vaccine coverage. We conducted a prospective cohort study of 349 participants from 52 households in The Gambia between March 2021 and June 2022, with routine weekly SARS-CoV-2 RT-PCR and 6-monthly SARS-CoV-2 serology. Attack rates of 45% and 57% were seen during Delta and Omicron BA.1 waves respectively. Eighty-four percent of RT-PCR-positive infections were asymptomatic. Children under 5-years had a lower incidence of infection than 18-49-year-olds. One prior SARS-CoV-2 infection reduced infection risk during the Delta wave only, with immunity from ≥2 prior infections required to reduce the risk of infection with early Omicron lineage viruses. In an African population with high levels of infection-driven immunity and low vaccine coverage, we find high attack rates during SARS-CoV-2 waves, with a high proportion of asymptomatic infections and young children remaining relatively protected from infection.
