The Pre-Vaccination Donated Blood Is Free from Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) but Is Rich with Anti-SARS-CoV-2 Antibodies: A Cross-Section Saudi Study

(1) Backgrounds and Objectives: Since its discovery, information about the severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) has spread rapidly. However, many issues remain unresolved. Coronaviruses are primarily transmitted through respiratory secretions. The possibility of transmission via donated blood transfusion deserves studying. This is the first study in Saudi Arabia to look at pre-vaccination donated blood anti-SARS-CoV-2 antibody content as a marker for virus transmission via viral RNA positive blood and/or the potential therapeutic value of convalescent plasma. (2) Methods: A total of 300 blood samples were sequentially collected from unvaccinated donors who donated blood to the blood bank of Prince Mutaib Bin Abdulaziz Hospital in Sakaka, Al-Jouf, Saudi Arabia. Specific ELISA was used to detect anti-SARS-CoV-2 IgG and IgM antibodies. SARS-CoV-2 was detected using specific real-time reverse-transcription PCR (rRT-PCR). (3) Results: The prevalence of anti-SARS-CoV-2 IgG was low (9%), whereas the prevalence of anti-SARS-CoV-2 IgM was high (65%). Relevant demographics, anthropometrics, and lifestyle factors revealed significant associations (p < 0.05) between IgM-positivity only vs. age (age group 21−30 years), postgraduate education, no history of international travel, IgG-negativity, and absence of experience with COVID-19-like symptoms. Furthermore, there are significant associations (p < 0.05) between IgG-positivity only vs. age (age group 21−30 years), postgraduate education, and being a non-healthcare worker. All donors in the anti-SARS-CoV-2 IgG-positive group (n = 27) had previously experienced symptoms similar to COVID-19 (p < 0.001) and most of them (n = 24) showed anti-SARS-CoV-2 IgM-positive test (p = 0.006). However, all the samples tested negative for SARS-CoV-2 RNA using rRT-PCR. (4) Conclusion: Our findings add to the growing body of evidence that donated blood is safe, with the added benefit of convalescent plasma rich in potentially neutralizing IgG and IgM against SARS-CoV-2.