학술논문
Omicron B.1.1.529 variant infections associated with severe disease are uncommon in a COVID-19 under-vaccinated, high SARS-CoV-2 seroprevalence population in MalawiResearch in context
Document Type
article
Author
Upendo L. Mseka; Jonathan Mandolo; Kenneth Nyoni; Oscar Divala; Dzinkambani Kambalame; Daniel Mapemba; Moses Kamzati; Innocent Chibwe; Marc Y.R. Henrion; Kingsley Manda; Deus Thindwa; Memory Mvula; Bright Odala; Raphael Kamng'ona; Nelson Dzinza; Khuzwayo C. Jere; Nicholas Feasey; Antonia Ho; Abena S. Amoah; Melita Gordon; Todd D. Swarthout; Amelia Crampin; Robert S. Heyderman; Matthew Kagoli; Evelyn Chitsa-Banda; Collins Mitambo; John Phuka; Benson Chilima; Watipaso Kasambara; Kondwani C. Jambo; Annie Chauma-Mwale
Source
EClinicalMedicine, Vol 56, Iss , Pp 101800- (2023)
Subject
Language
English
ISSN
2589-5370
Abstract
Summary: Background: The B.1.1.529 (Omicron) variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has resulted in the fourth COVID-19 pandemic wave across the southern African region, including Malawi. The seroprevalence of SARS-CoV-2 antibodies and their association with epidemiological trends of hospitalisations and deaths are needed to aid locally relevant public health policy decisions. Methods: We conducted a population-based serosurvey from December 27, 2021 to January 17, 2022, in 7 districts across Malawi to determine the seroprevalence of SARS-CoV-2 antibodies. Serum samples were tested for antibodies against SARS-CoV-2 receptor binding domain using WANTAI SARS-CoV-2 Receptor Binding Domain total antibody commercial enzyme-linked immunosorbent assay (ELISA). We also evaluated COVID-19 epidemiologic trends in Malawi, including cases, hospitalisations and deaths from April 1, 2021 through April 30, 2022, collected using the routine national COVID-19 reporting system. A multivariable logistic regression model was developed to investigate the factors associated with SARS-CoV-2 seropositivity. Findings: Serum samples were analysed from 4619 participants (57% female; 60% aged 18–50 years), of whom 878/3794 (23%) of vaccine eligible adults had received a single dose of any COVID-19 vaccine. The overall assay-adjusted seroprevalence was 83.7% (95% confidence interval (CI), 79.3%–93.4%). Seroprevalence was lowest among children