CLEVELAND, Ohio – Recent genetic studies suggest that people with certain blood types may be more likely to develop a severe form of COVID-19.
A genetic study of 1,610 COVID-19 patients in Italy and Spain suggested that having type A blood resulted in a 50 percent increase in the probability that a patient would need oxygen or a respirator, according to press reports. These preliminary findings have not yet been reviewed by other scientists.
Other studies published earlier this year reached similar conclusions, including reports from a New York hospital and a peer-reviewed study from Wuhan.
This research could lead to the development of a DNA test to identify patients who will become ill or help drug developers find new treatments for COVID-19, according to a report published in The New York Times.
“It’s very interesting, but there is more we need to learn,” Dr. Erin Goodhue, executive medical director of direct patient care for the American Red Cross, said of genetic studies.
Much more research is needed before possible links between COVID-19 and blood type are fully understood, Goodhue said.
The reasons why blood types could affect COVID-19 are unknown, The New York Times said. Genetic variations can influence whether, in some people, the coronavirus triggers an overreaction of the immune system, causing massive inflammation and lung damage.
Ads about these studies have raised questions about the science behind blood typing. Here are the responses from Goodhue, the Red Cross, Healthline and WebMD.
What is the blood type?
Blood types are determined by the presence or absence of certain antigens, which are proteins, fats, and sugars found in red blood cells. Blood type is inherited based on your parents’ blood types.
There are four main blood groups determined by the presence or absence of two antigens, A and B, on the surface of red blood cells. In addition to the A and B antigens, there is a protein called Rh factor, which can be present or absent.
Why can’t a person with type A blood receive a type B blood transfusion?
Antigens can trigger an immune response if they are foreign to the body. People with type A blood make strong antibodies against type B blood and vice versa. There are no antibodies against type 0 blood. Safe blood transfusions depend on careful blood typing and cross-comparison.
How many different blood types are there?
There are eight types of blood:
A positive or a negative
B positive or B negative
AB positive or AB negative
O positive or O negative
What is the most common blood type?
O positive is the most common blood type in the United States (37%), closely followed by A positive (35.7%), according to the Stanford School of Medicine Blood Center.
AB negative (.6%) and B negative (1.5%) are the two least common blood types among Americans.
What is a universal blood donor?
Universal red blood cell donors are those with a negative O blood type because their can of blood can be used for transfusions in patients with any type of blood. It is used for emergency transfusions and is generally scarce and in high demand by hospitals.
Universal plasma donors have AB type blood. Plasma is the portion of clear, liquid blood that remains after red and white blood cells, platelets, and other cellular components have been removed.
Rh negative blood is administered to Rh negative patients and Rh positive or Rh negative blood can be administered to Rh positive patients.
How can I know my blood type?
Get a blood test at your doctor’s office or sign up to donate blood. Home blood type tests are not always accurate.
