The impact of blood group phenotypes on COVID-19 severity and mortality in Duhok province: a prospective cross-sectional study


  • Fatima Jaafar Rasho Department of Medical Laboratory Sciences, College of Health Sciences, University of Duhok, Duhok, Kurdistan Region, Iraq.
  • Muayad Aghali Merza Department of Internal Medicine, Azadi Teaching Hospital, College of Medicine, University of Duhok, Duhok, Kurdistan Region, Iraq.



COVID-19, Severity, Outcome, Blood group


Objectives: This study aimed to determine the frequency of blood group types among COVID-19 patients and to investigate its potential association with disease severity and patient outcomes.

Methods: this prospective cross-sectional study was conducted from February to July 2022 in three different healthcare facilities in the Duhok region. All confirmed PCR confirmed COVID-19 patients were classified into: mild, moderate, severe, and critical cases. Information on demographic, clinical, and laboratory characteristics were collected using a standardized questionnaire. All patients were subjected to ABO blood grouping. The statistical calculations were performed by JMP Pro 14.3.0. A p value of < 0.05 was considered significant.

Results: the study comprised of 404 patients. The age range of the patients varied from 16 to 100 years with a male predominance (204, 50.5%). Out of the total patients, 250 (61.88%) had mild-moderate course, while 154 (38.12%) had severe-critical course. The most frequent blood group was O (164, 41.58%), followed by blood group A (121, 29.95%). There was no significant difference in the distribution of the Rh factor among the studied subjects (p=0.426). There was a significant increase in disease severity and worse outcome with increasing age (p=<0.0001). Considering blood group types, there were no significant differences between blood group types with COVID-19 severity and patients’ outcome.  

Conclusions: individuals with blood group O may have a higher risk of contracting COVID-19. Advanced age is a crucial predictor of disease severity and poor outcomes. There were no significant association between blood group types with COVID-19 severity and patients’ outcome. However, further research is needed to confirm these findings and determine the underlying mechanisms behind any potential association between blood groups and COVID-19 susceptibility, severity, and outcome.


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How to Cite

Rasho, F. J. ., & Aghali Merza, M. . (2023). The impact of blood group phenotypes on COVID-19 severity and mortality in Duhok province: a prospective cross-sectional study. Journal of Contemporary Medical Sciences, 9(2).