Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2022 Sep 16;19(18):11664.
doi: 10.3390/ijerph191811664.

High Seroprevalence of SARS-CoV-2 in Mwanza, Northwestern Tanzania: A Population-Based Survey

Affiliations

High Seroprevalence of SARS-CoV-2 in Mwanza, Northwestern Tanzania: A Population-Based Survey

Helmut A Nyawale et al. Int J Environ Res Public Health. .

Abstract

The transmission of the SARS-CoV-2 virus, which causes COVID-19, has been documented worldwide. However, the evidence of the extent to which transmission has occurred in different countries is still to be established. Understanding the magnitude and distribution of SARS-CoV-2 through seroprevalence studies is important in designing control and preventive strategies in communities. This study investigated the seropositivity of the SARS-CoV-2 virus antibodies in the communities of three different districts in the Mwanza region, Tanzania. A household cross-sectional survey was conducted in September 2021 using the modified African Centre for Disease and Prevention (ACDC) survey protocol. A blood sample was obtained from one member of each of the selected households who consented to take part in the survey. Immunochromatographic rapid test kits were used to detect IgM and IgG SARS-CoV-2 antibodies, followed by descriptive data analysis. Overall, 805 participants were enrolled in the study with a median age of 35 (interquartile range (IQR):27-47) years. The overall SARS-CoV-2 seropositivity was 50.4% (95%CI: 46.9-53.8%). The IgG and IgM seropositivity of the SARS-CoV-2 antibodies was 49.3% and 7.2%, respectively, with 6.1% being both IgG and IgM seropositive. A history of runny nose (aOR: 1.84, 95%CI: 1.03-3.5, p = 0.036), loss of taste (aOR: 1.84, 95%CI: 1.12-4.48, p = 0.023), and living in Ukerewe (aOR: 3.55, 95%CI: 1.68-7.47, p = 0.001) and Magu (aOR: 2.89, 95%CI: 1.34-6.25, p= 0.007) were all independently associated with SARS-CoV-2 IgM seropositivity. Out of the studied factors, living in the Ukerewe district was independently associated with IgG seropositivity (aOR 1.29, CI 1.08-1.54, p = 0.004). Twenty months after the first case of COVID-19 in Tanzania, about half of the studied population in Mwanza was seropositive for SARS-CoV-2.

Keywords: COVID-19; Mwanza; SARS-CoV-2; Tanzania; antibodies; seroprevalence.

PubMed Disclaimer

Conflict of interest statement

The authors declare no conflict of interest.

Figures

Figure 1
Figure 1
Venn diagram showing the distribution of serological markers among the participants.
Figure 2
Figure 2
Geographical distribution of the participants with SARS-CoV-2 IgG positive in the districts of Misungwi, Magu, and Ukerewe in Mwanza, Tanzania.

References

    1. Musa H.H., Musa T.H., Musa I.H., Musa I.H., Ranciaro A. Since January 2020 Elsevier Has Created a COVID-19 Resource Centre with Free Information in English and Mandarin on the Novel Coronavirus COVID-19. The COVID-19 Resource Centre Is Hosted on Elsevier Connect, The Company’s Public News and Information. Elsevier; Amsterdam, The Netherlands: 2020.
    1. Gaye B., Khoury S., Cene C.W., Kingue S., N’Guetta R., Lassale C., Baldé D., Diop I.B., Dowd J.B., Mills M.C., et al. Socio-demographic and epidemiological consideration of Africa’s COVID-19 response: What is the possible pandemic course? Nat. Med. 2020;26:996–999. doi: 10.1038/s41591-020-0960-y. - DOI - PubMed
    1. Bell D., Hansen K.S., Kiragga A.N., Kambugu A., Kissa J., Mbonye A.K. Predicting the impact of COVID-19 and the potential impact of the public health response on disease burden in Uganda. Am. J. Trop. Med. Hyg. 2020;103:1191–1197. doi: 10.4269/ajtmh.20-0546. - DOI - PMC - PubMed
    1. Usuf E., Roca A. Seroprevalence surveys in sub-Saharan Africa: What do they tell us? Lancet Glob. Health. 2021;9:e724–e725. doi: 10.1016/S2214-109X(21)00092-9. - DOI - PubMed
    1. Tarimo C.S., Wu J. The first confirmed case of COVID-19 in Tanzania: Recommendations based on lesson learned from China. Trop. Med. Health. 2020;48:25. doi: 10.1186/s41182-020-00214-x. - DOI - PMC - PubMed

Publication types