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bioRxiv · 10.1101/2020.10.13.337287

Sero-prevalence of anti-SARS-CoV-2 Antibodies in Addis Ababa, Ethiopia

Nega, B.·Addissie, A.·Mamo, G.·Deyessa, N.·Abebe, T.·Abagero, A.·Ayele, W.·Abebe, W.·Haile, T.·Argaw, R.·Amogne, W.·Belachew, A.·Desalegn, Z.·Teka, B.·Kantelhardt, E.·Wossen, M.·Abdella, S.·Tollera, G.·Tadesse, L.
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Abstract

BackgroundAnti-SARS-CoV-2 antibody tests are being increasingly used for sero-epidemiological purposes to provide better understanding of the extent of the infection in the community, and monitoring the progression of the COVID-19 epidemic. We conducted sero-prevalence study to estimate prior infection with with SARS-CoV-2 in Addis Ababa. MethodsA cross-sectional study was done from April 23 to 28, 2020 among 301 randomly selected residents of Addis Ababa; with no known history of contact with confirmed COVID-19 person. Interviews on socio demographic and behavioural risk factor followed by serological tests were performed for SARS-CoV-2 IgM, and IgG antibodies, using COVID-19 IgG/IgM Rapid Test Cassette. The test has sensitivity of 87{middle dot}9% and specificity of 100% for lgM; and a sensitivity of 97{middle dot}2% and specificity of 100% for IgG. RT-PCR test was also done on combined nasopharyngeal and oropharengeal swabs as an important public health consideration. FindingsThe unadjusted antibody-based crude SARS-CoV-2 prevalence was 7{middle dot}6% and the adjusted true SARS-CoV-2 prevalence was estimated at 8{middle dot}8% (95% CI 5{middle dot}5%-11{middle dot}6%) for the study population. Higher sero-prevalence were observed for males (9.0%), age below 50 years (8.2%), students and unemployed (15.6%), those with primary education (12.1%), smokers (7.8%), alcohol consumers (8.6%), chatt-chewers (13.6%) and shish smokers (18.8%). Seroprevalence was not significantly associated neither with socio-demographic not behavioral characteristics. According to the findings, possibly more individuals had been infected in Addis Ababa than what was being detected and reported by RT-PCR test suggestive of community transmission. The use of serological test for epidemiological estimation of the extent of SARS-CoV-2 epidemic gives a more precise estimate of magnitude which would be used for further monitoring and surveillance of the magnitude of the SARS CoV-2 infection.

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Nega, B., Addissie, A., Mamo, G., Deyessa, N., Abebe, T., Abagero, A., Ayele, W., Abebe, W., Haile, T., Argaw, R., Amogne, W., Belachew, A., Desalegn, Z., Teka, B., Kantelhardt, E., Wossen, M., Abdella, S., Tollera, G., Tadesse, L.. 2020-10-13. Sero-prevalence of anti-SARS-CoV-2 Antibodies in Addis Ababa, Ethiopia. https://doi.org/10.1101/2020.10.13.337287

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