Author:
Etyang Anthony O.,Adetifa Ifedayo,Omore Richard,Misore Thomas,Ziraba Abdhalah K.,Ng’oda Maurine A.,Gitau Evelyn,Gitonga John,Mugo Daisy,Kutima Bernadette,Karanja Henry,Toroitich Monica,Nyagwange James,Tuju James,Wanjiku Perpetual,Aman Rashid,Amoth Patrick,Mwangangi Mercy,Kasera Kadondi,Ng’ang’a Wangari,Akech Donald,Sigilai Antipa,Karia Boniface,Karani Angela,Voller Shirine,Agoti Charles N.,Ochola-Oyier Lynette I.,Otiende Mark,Bottomley Christian,Nyaguara Amek,Uyoga Sophie,Gallagher Katherine,Kagucia Eunice W.,Onyango Dickens,Tsofa Benjamin,Mwangangi Joseph,Maitha Eric,Barasa Edwine,Bejon Philip,Warimwe George M.,Scott J Anthony G,Agweyu Ambrose
Abstract
ABSTRACTBackgroundMost of the studies that have informed the public health response to the COVID-19 pandemic in Kenya have relied on samples that are not representative of the general population. We conducted population-based serosurveys at three Health and Demographic Surveillance Systems (HDSSs) to determine the cumulative incidence of infection with SARS-CoV-2.MethodsWe selected random age-stratified population-based samples at HDSSs in Kisumu, Nairobi and Kilifi, in Kenya. Blood samples were collected from participants between 01 Dec 2020 and 27 May 2021. No participant had received a COVID-19 vaccine. We tested for IgG antibodies to SARS-CoV-2 spike protein using ELISA. Locally-validated assay sensitivity and specificity were 93% (95% CI 88-96%) and 99% (95% CI 98-99.5%), respectively. We adjusted prevalence estimates using classical methods and Bayesian modelling to account for the sampling scheme and assay performance.ResultsWe recruited 2,559 individuals from the three HDSS sites, median age (IQR) 27 (10-78) years and 52% were female. Seroprevalence at all three sites rose steadily during the study period. In Kisumu, Nairobi and Kilifi, seroprevalences (95% CI) at the beginning of the study were 36.0% (28.2-44.4%), 32.4% (23.1-42.4%), and 14.5% (9.1-21%), and respectively; at the end they were 42.0% (34.7-50.0%), 50.2% (39.7-61.1%), and 24.7% (17.5-32.6%), respectively. Seroprevalence was substantially lower among children (<16 years) than among adults at all three sites (p≤0.001).ConclusionBy May 2021 in three broadly representative populations of unvaccinated individuals in Kenya, seroprevalence of anti-SARS-CoV-2 IgG was 25-50%. There was wide variation in cumulative incidence by location and age.
Publisher
Cold Spring Harbor Laboratory
Reference24 articles.
1. COVID-19 situation reports. (Accessed 02 January 2022, at https://www.health.go.ke/#1591180376422-52af4c1e-256b.)
2. Temporal trends of SARS-CoV-2 seroprevalence during the first wave of the COVID-19 epidemic in Kenya;Nature Communications,2021
3. Seroprevalence of Antibodies to Severe Acute Respiratory Syndrome Coronavirus 2 Among Healthcare Workers in Kenya;Clin Infect Dis,2022
4. Anti-Severe Acute Respiratory Syndrome Coronavirus 2 Immunoglobulin G Antibody Seroprevalence among Truck Drivers and Assistants in Kenya;Open Forum Infectious Diseases,2021
5. Lucinde R , Mugo D , Bottomley C , et al. Sero-surveillance for IgG to SARS-CoV-2 at antenatal care clinics in two Kenyan referral hospitals. medRxiv 2021:2021.02.05.21250735.