Most Kenyans appear less susceptible to severe Covid-19, at least according to a small study that shows those with blood group A are more susceptible and those with O most protected.
According to the Kenya National Blood Transfusion Services, most Kenyans have blood group O. "One in three of the population has this group," KNBTS says.
Only about 24 per cent of Kenyans have blood group A, which is the most susceptible.
A recent study published in the New England Journal of Medicine, suggested that blood group O is associated with a risk of acquiring Covid-19 that was lower than that in non-O blood groups.
On the other hand, blood group A was associated with a higher risk than non-A blood group, according to the study.
The study corroborates other studies, including one from Wuhan, China, where the SARS-CoV-2 virus outbreak originated.
"It also corroborates a 2003 study on SARS-Cov-1 which showed people with blood group A were most susceptible to severe Sars disease, and those with O had the least risk," public health expert Dr Bernard Muia told the Star.
Dr Muia also served as head of research at the Ministry of Health. He said Kenya has little research on blood types and their implications on health.
"This association is there and the Ministry of Health needs to add blood group to the list of biodata for all patients diagnosed with Covid-19," he said.
Currently, the variables given include sex, age and social status.
Scientists do not know exactly why blood type could influence a person’s susceptibility to these viruses, but authors of the NEJM paper suggest that variations in biological mechanisms in ABO blood groups may play a role, specifically in their immune response.
“Also, there are some theories about how some of these ABO genes, based on the protein they’re encoding, might affect some of the receptors where the virus binds and can alter how someone becomes more or less susceptible to the virus,” said Dr Ang Li, an assistant professor of haematology and oncology at Baylor College of Medicine in the US, according to a publication by the university.
Dr Muia called for better funding for medical research in Kenya.
"The future of public health and development relies on how much we do research," he said.
A person’s blood type is determined by the presence or absence of specific antigens—A and B—which are molecules on red blood cells that trigger an immune response.
A person with Type A blood has the A antigen on red cells and a B antibody on their plasma; a person with Type B has the B antigen on red cells and A antibodies on their plasma.
Individuals with Type AB have both A and B antigens on their red cells, but neither on their plasma, and those with Type O have neither A nor B antigens on their red cells, but both antibodies are present on their plasma.
One theory is that because the immune systems of people with Type O blood already have antibodies for both A and B, their bodies are more equipped to identify foreign proteins—including those on the surface of viruses.
(edited by o. owino)
