Dramatic Rise of Seroprevalence Rates of SARS-CoV-2 Antibodies among Healthy Blood Donors: The evolution of a Pandemic

Sughayer, Maher A.; Mansour, Asem; Al Nuirat, Abeer; Souan, Lina; Ghanem, Mohammad; Siag, Mahmoud

Background Seroprevalence studies of SARS-CoV-2 antibodies are useful in assessing the epidemiological status in the community and the degree of spread. Objective To study the seroprevalence rates of SARS-CoV-2 antibodies among healthy blood donors in Jordan, at various points of time as the pandemic evolves in the community. Methods A total of 1374 blood donor were tested for the SARS-CoV-2 total immunoglobulin antibodies in 3 groups. The first and second group: 746 and 348 individuals were tested in June and September-2020 respectively. The 3rd group of 292 were tested in February-2021. We utilized a qualitative assay (specificity: 99.8%, sensitivity: 100%). Results The first 2 groups (January-September, 2020) when the number of confirmed Covid-19 cases were several hundred-3000 showed a seroprevalence rate of 0% (95% CI 0.00%-0.51%). The 3rd group (early February 2021), when the number reported confirmed case has reached 100 folds that of September 2020, revealed a seroprevalence of 27.4% (95% CI 22.5%-32.9%). Conclusions a dramatic rise in seroprevalence of SARS-CoV-2 antibodies was seen among healthy blood donors in Jordan in parallel with wide-spread intracommunity transmission of the disease. This information is useful to assess the degree of herd immunity and provides for better understanding of the pandemic.