The evidence on whether a person’s blood type is associated with risk of contracting COVID-19 is inconclusive, because only a few studies have been carried out to examine this claim and any differences that have been found between blood groups have been small.
At the time of our search, two studies from the US, one study from China and one study from the UK had examined this question.
A study which looked at the blood group of patients diagnosed with COVID-19 in a New York hospital, found higher numbers of patients with blood group B and a lower numbers of patients with blood group O, when compared to patients not diagnosed with COVID-19 attending the same hospital. However, differences in patients such as age, sex, blood pressure, diabetes, weight, and chronic cardiovascular and lung disorders could influence these rates. When these factors were taken into consideration by the authors this difference between the blood groups did not remain.
The US study also combined their data with data from studies conducted in China and the UK. These results demonstrated a greater proportion of Type B blood groups and lower proportion of Type O blood groups among COVID-19 patients compared to people who tested negative.
A further small observational study observed that patients in a US hospital with blood types B and AB who received a COVID-19 test were more likely to test positive and those with blood type O were less likely to test positive.
Two small observational studies in the UK and China found that those with blood type A were more likely to test positive for Covid-19. Patients with blood type O were less likely to be diagnosed with COVID-19 than those with other blood types. Blood type was not associated with hospitalisation among those diagnosed with COVID-19.
In summary, the evidence on whether blood type is associated with a person’s risk of contracting COVID-19 is to protect yourself and others from coronavirus, please continue to follow public health advice to maintain social distancing and wash your hands properly and often.
Things to Remember
Beware of claims based on a single study. Ask if there are other studies that examine the same question and a careful summary of all the relevant studies.
Beware of claims that are based on before and after comparisons and when people don’t say what a treatment was compared to. Remember: Ask what the treatment was compared to, and whether it was a fair comparison.
Privacy & Cookies Policy
Necessary cookies are absolutely essential for the website to function properly. This category only includes cookies that ensures basic functionalities and security features of the website. These cookies do not store any personal information.
Any cookies that may not be particularly necessary for the website to function and is used specifically to collect user personal data via analytics, ads, other embedded contents are termed as non-necessary cookies. It is mandatory to procure user consent prior to running these cookies on your website.