Abstract:

Background: The current COVI-19 pandemic is caused by corona virus named Severe Acute Respiratory Syndrome Corona Virus-2 (SARS-CoV-2). The COVID-19 pandemic has got significant morbidity and mortality worldwide. Transmission of SARS-CoV-2 occurs primarily through respiratory droplets and aerosols generated during coughing or sneezing which may land on mouth or nose. WHO suggests that there is also a possibility of blood to blood transfer of SARS-CoV-2 from one person to another during blood transfusion if the donor is infected with SARS-CoV-2 but, there is lack of information concerning the seroprevalence and factors associated with of SARS-CoV-2 among unvaccinated blood donors in Tanzania. Hence this study aimed at getting information on seroprevalence and factors associated with SARS-CoV-2 among unvaccinated blood donors in Mwanza region Tanzania.

Methodology: Analytical cross section study was designed and conducted for two months among blood donors at Lake Zone Blood Transfusion center (LTBC) and Bugando Medical Centre (BMC). A total 152 blood donors were enrolled in this study. Blood samples were collected from blood donors who agreed to participate in the study and samples were stored in a refrigerator at 2-8º .Social demographics data were collected from participants using questionnaires. Detection of IgM/IgG antibodies against SARS-CoV-2 was done using RADI COVID-19 IgM/IgG Rapid test kit device. This rapid test kit has got sensitivity of 90% and specificity of 100%. Data results were recorded in a logbook then transferred to Microsoft Excell.The data analysis was done using STATA version 13.

Results: Out of 152 blood samples 61 samples tested positive for antibodies against SARS-CoV-2.Hence the seroprevalence of SARS-CoV-2 among unvaccinated blood donors in Mwanza, Tanzania is 40.1% .IgG seropositivity was 39% while IgM seropositivity was 4%. Seropositivity for both IgM and IgG was 2%. On univalent analysis, occupation (OR=0.01, 95% CI=0.013-0.457, P-value=0.01) showed significant association with the seropositivity. Also on multivalent analysis, occupation (OR=0.085, 95% CI=0.012-0.599, P¬-value=0.013) showed significant association with seropositivity of SARS-CoV-2.

Conclusion: More than 2 years after the case of SARS-CoV-2, the findings indicate more than one third of the blood donors are exposed to SARS-CoV-2 and very few number of active cases of SARSCoV-2 infection.