Abstract
OBJECTIVES: To determine the association between ABO/Rh-D blood types and susceptibility to SARS-CoV-2 infection in Pakistan. METHODS: In this cross-sectional study, 1935 confirmed cases of COVID-19 were included using consecutive sampling. Age and gender-matched sample of 1935 blood donors was used as a comparison group. Chi-square test and binary logistic regression were used for inferential statistics. RESULTS: Significantly higher proportion of blood type-B was observed in COVID-19 group (35.9% vs 31.9%, p=0.009). Blood type-AB was found more frequently (14.2% vs 11.8%, p=0.03) in the comparison group. The Rh-D Positive blood types were 93.3% in COVID-19 group and 94.9% in comparison group (p=0.03). The odds of blood type-B, AB and Rh-D positive to test positive for SARS-CoV-2 were 1.195 (95% CI 1.04 - 1.36, p=0.009), 0.80 (95% CI 0.66 - 0.97, p=0.03) and 0.75 (95% CI 0.57- 0.98, p = 0.03), respectively. Blood types A and O did not have significant association with SARS-CoV-2 PCR result (p = 0.22 and 0.88, respectively). CONCLUSIONS: There is significant association between blood types B & AB and susceptibility to COVID-19. There is no association between blood types A and O with COVID-19. Rh- D positive blood types are less susceptible to COVID-19.