People with blood groups A, B and Rh+ are more susceptible to Covid-19 infection whereas O, AB and Rh- are at lower risk of infection, according to a study released on Tuesday by Delhi-based Ganga Ram Hospital (SGRH).

The research, published in the journal Frontiers in Cellular and Infection Microbiology, showed that male patients of blood group B are more prone to Covid-19 than the female patients with blood group B.

Blood sample
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The study was conducted on 2,586 Covid-19 positive patients tested through real-time PCR who were admitted at SGRH from April 8, 2020 to October 4, 2020.

In the 2,586 Covid-19-infected patients, the frequencies of A, B, O, and AB were 29.93 per cent, 41.80 per cent, 21.19 per cent, and 7.98 per cent, respectively. People less than 60 years with blood group AB were found to be more prone to Covid infection.

However, the study found no association between blood groups and susceptibility to severity of disease as well as mortality.

"Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is a new virus, and it is unclear whether blood groups have any impact on Covid-19 risk or progression. Therefore, we investigated the association of ABO and Rh blood group with Covid-19 susceptibility, prognosis, recovery time, and mortality in this study," said Dr. Rashmi Rana, Consultant, Department of Research, SGRH, in a statement.

The research also found people with blood group A and Rh+ types are associated with a decrease in recovery period, whereas those with blood group O and Rh- could recover faster compared to people of other blood groups.

"However, the ABO and/or Rh blood groups may not be responsible for this association, as these may indicate an unexplored underlying factor like co-morbidity. Therefore, larger, multicenter, and prospective studies are needed to ascertain the relationship between blood groups and SARS-CoV-2," said Dr. Vivek Ranjan, Co-author and Chairperson, Department of Blood Transfusion, at SGRH.

Of all the patients studied, 98.07 per cent were Rh+. Blood group A and B are observed to be significantly associated with Covid-19 susceptibility, whereas blood group O and AB have low risk of Covid-19 infection.