Best Evidence Topic report: does blood group type O decrease the risk of severe COVID-19 infection?

Area of Science:

• Infectious Diseases
• Hematology
• Epidemiology

Background:

• The association between blood group type and COVID-19 severity has been investigated.
• Understanding potential risk factors is crucial for managing the pandemic.

Purpose of the Study:

• To systematically review evidence on whether blood group type O is associated with a lower risk of severe COVID-19 infection compared to non-O blood groups.

Main Methods:

• A short-cut systematic review was performed.
• Searches were conducted in MEDLINE, Embase, and Cochrane databases.
• Seventeen studies were selected to answer the research question.

Main Results:

• Four out of 17 studies suggested a potential association between blood group O and lower risk of severe COVID-19.
• Thirteen studies reported no significant relationship between blood group O and COVID-19 severity.
• Three identified systematic reviews and meta-analyses found no protective effect of blood group O.

Conclusions:

• Current evidence does not support the hypothesis that blood group type O offers protection against severe outcomes in COVID-19 patients.
• Further research may be needed to definitively establish any link.
• Blood group type O is not a confirmed protective factor for severe COVID-19.