TITLE:
Seroprevalence of SARS-COV-2 Exposure among “High-Risk” Populations (Healthcare Workers, People Who Attend Markets, and School Children) in Zanzibar
AUTHORS:
Ame Masemo, Solomon Mwakasungula, Khamis Kheir, Erick Mgina, Nahya Khamis, Irabi Kassim, Bihila Bakar, Khamis Salim, Sarah Mswata, Kibwana Omar, Theckla Kazimoto, Linzy Elton, Honorati Masanja, Mayassa Ally
KEYWORDS:
SARS-CoV-2, Seroprevalence, Zanzibar, ELISA, COVID-19
JOURNAL NAME:
Advances in Infectious Diseases,
Vol.14 No.1,
January
25,
2024
ABSTRACT: In Zanzibar, from the start of the pandemic in March 2020 to the time of sampling in December 2020, SARS-CoV-2 seroprevalence data was limited. We conducted a seroprevalence study to evaluate the magnitude of SARS-CoV-2 exposure among healthcare workers, school children, and people who attended general markets in Zanzibar. The objectives of the study were to analyse the total antibodies from selected higher-risk population groups in order to determine magnitude in SARS CoV-2 exposure. Blood samples were collected from eligible and consented participants (adults and children), and their serum was analyzed for total antibodies against SARS-CoV-2 using ELISA. A questionnaire was used to collect participants’ demographic and clinical data. The overall SARS-CoV-2 seroprevalence across all age groups was 33%, and a higher seroprevalence was observed in the 40 - 49 years’ age group relative to other ages as well as in those who attended markets. A runny nose (18.8% of participants) was the most frequently reported SARS-CoV-2 infection-related symptom. Multivariable analysis showed significantly higher odds of infection in people living in urban districts. The findings provide insight into SARS-CoV-2 infection among school children, health workers, and people who attended markets in Zanzibar in the early stages of the pandemic. Exposure in these groups might have been influenced by infection and prevention strategies taken by the government, as well as shopping behavior, school overcrowding, and population density in urban settings. The study had methodological limitations, including cross-sectional design. Further, well-designed, longitudinal studies are recommended to understand exposure and transmission at a population level.