"A total of 32,970 individuals were tested for SARS-CoV-2 antibodies with the blood specimens drawn between May 12-July 12, with a median day of June 28. A total of 5,448 individuals had detectable antibodies. The weighted (for total population of Qatar) antibody prevalence was 24.0%". There were significant differences in antibody prevalence by sex and nationality. After controlling for confounders, odds of antibody positivity in males were 2.9-fold higher than females, and were highest among Bangladeshis and Nepalese, lowest among Qataris. Odds also increased incrementally with age. Overall, antibody positivity was >88% among those who had their first positive PCR test >15 days before the antibody test."