tetano
Editor, Senior Moderator
Nat Commun
. 2024 May 7;15(1):3814.
doi: 10.1038/s41467-024-48098-3. High SARS-CoV-2 incidence and asymptomatic fraction during Delta and Omicron BA.1 waves in The Gambia
Sheikh Jarju[SUP] #[/SUP][SUP] 1 [/SUP], Rhys D Wenlock[SUP] #[/SUP][SUP] 1 [/SUP], Madikoi Danso[SUP] 1 [/SUP], Dawda Jobe[SUP] 1 [/SUP], Ya Jankey Jagne[SUP] 1 [/SUP], Alansana Darboe[SUP] 1 [/SUP], Michelle Kumado[SUP] 1 [/SUP], Yusupha Jallow[SUP] 1 [/SUP], Mamlie Touray[SUP] 1 [/SUP], Ebrima A Ceesay[SUP] 1 [/SUP], Hoja Gaye[SUP] 1 [/SUP], Biran Gaye[SUP] 1 [/SUP], Abdoulie Tunkara[SUP] 1 [/SUP], Sheriff Kandeh[SUP] 1 [/SUP], Marie Gomes[SUP] 1 [/SUP], Ellen Lena Sylva[SUP] 1 [/SUP], Fatoumata Toure[SUP] 1 [/SUP], Hailey Hornsby[SUP] 2 3 [/SUP], Benjamin B Lindsey[SUP] 2 3 [/SUP], Martin J Nicklin[SUP] 2 3 [/SUP], Jon R Sayers[SUP] 2 3 [/SUP], Abdul K Sesay[SUP] 1 [/SUP], Adam Kucharski[SUP] 4 [/SUP], David Hodgson[SUP] 4 [/SUP], Beate Kampmann[SUP] 5 6 [/SUP], Thushan I de Silva[SUP] 7 8 9 [/SUP]
Affiliations
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.
. 2024 May 7;15(1):3814.
doi: 10.1038/s41467-024-48098-3. High SARS-CoV-2 incidence and asymptomatic fraction during Delta and Omicron BA.1 waves in The Gambia
Sheikh Jarju[SUP] #[/SUP][SUP] 1 [/SUP], Rhys D Wenlock[SUP] #[/SUP][SUP] 1 [/SUP], Madikoi Danso[SUP] 1 [/SUP], Dawda Jobe[SUP] 1 [/SUP], Ya Jankey Jagne[SUP] 1 [/SUP], Alansana Darboe[SUP] 1 [/SUP], Michelle Kumado[SUP] 1 [/SUP], Yusupha Jallow[SUP] 1 [/SUP], Mamlie Touray[SUP] 1 [/SUP], Ebrima A Ceesay[SUP] 1 [/SUP], Hoja Gaye[SUP] 1 [/SUP], Biran Gaye[SUP] 1 [/SUP], Abdoulie Tunkara[SUP] 1 [/SUP], Sheriff Kandeh[SUP] 1 [/SUP], Marie Gomes[SUP] 1 [/SUP], Ellen Lena Sylva[SUP] 1 [/SUP], Fatoumata Toure[SUP] 1 [/SUP], Hailey Hornsby[SUP] 2 3 [/SUP], Benjamin B Lindsey[SUP] 2 3 [/SUP], Martin J Nicklin[SUP] 2 3 [/SUP], Jon R Sayers[SUP] 2 3 [/SUP], Abdul K Sesay[SUP] 1 [/SUP], Adam Kucharski[SUP] 4 [/SUP], David Hodgson[SUP] 4 [/SUP], Beate Kampmann[SUP] 5 6 [/SUP], Thushan I de Silva[SUP] 7 8 9 [/SUP]
Affiliations
- PMID: 38714680
- PMCID: PMC11076623
- DOI: 10.1038/s41467-024-48098-3
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.