What do we know about the association between blood type and severe reaction to COVID-19
What do we know about the association between blood type and severe reaction to COVID-19
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As of now, there is not enough evidence to indicate whether or not there may be some connection between blood type and COVID-19 risk, though the link is likely to be minimal if it does exist. Studies previously cited in the news suggested that Type A blood could be associated with higher risks of severe cases of COVID-19, and reporting included studies that had not yet been assessed by scientific experts (referred to in science as the peer-review process). One of these recent studies had been peer-reviewed and published in the New England Journal of Medicine (NEJM); however it used genes to determine the blood type, which is a method that is not very accurate. The gene testing company, 23andMe, recently released the preprint of a study (awaiting peer-review and using a similar gene association method) that identifies a strong association between blood type and COVID-19 diagnosis. The study suggests that people with blood group O tested positive less often compared to people with other blood groups, under similar circumstances. Two more recent studies from Columbia University and Massachusetts General Hospital in the U.S. found that blood type is not associated with risks of intubation or death from COVID-19, after adjusting for other factors. While scientists continue to learn more, age and underlying health conditions remain more significant risk factors for severe COVID-19 symptoms, and Type A blood is not thought to be a major risk factor at this time. While some studies have suggested a potential risk reduction for people with Type O blood, not all the studies have been peer-reviewed and the use of blood donors as study participants can give the appearance of Type O being more protective than it is (Type O blood is over-represented in blood donors, compared to the general population). Type O blood does not mean immunity to COVID-19.
As of now, there is not enough evidence to indicate whether or not there may be some connection between blood type and COVID-19 risk, though the link is likely to be minimal if it does exist. Studies previously cited in the news suggested that Type A blood could be associated with higher risks of severe cases of COVID-19, and reporting included studies that had not yet been assessed by scientific experts (referred to in science as the peer-review process). One of these recent studies had been peer-reviewed and published in the New England Journal of Medicine (NEJM); however it used genes to determine the blood type, which is a method that is not very accurate. The gene testing company, 23andMe, recently released the preprint of a study (awaiting peer-review and using a similar gene association method) that identifies a strong association between blood type and COVID-19 diagnosis. The study suggests that people with blood group O tested positive less often compared to people with other blood groups, under similar circumstances. Two more recent studies from Columbia University and Massachusetts General Hospital in the U.S. found that blood type is not associated with risks of intubation or death from COVID-19, after adjusting for other factors. While scientists continue to learn more, age and underlying health conditions remain more significant risk factors for severe COVID-19 symptoms, and Type A blood is not thought to be a major risk factor at this time. While some studies have suggested a potential risk reduction for people with Type O blood, not all the studies have been peer-reviewed and the use of blood donors as study participants can give the appearance of Type O being more protective than it is (Type O blood is over-represented in blood donors, compared to the general population). Type O blood does not mean immunity to COVID-19.
Publication
What our experts say
As of now, there is not enough evidence to indicate whether or not there may be some connection between blood type and COVID-19 risk, though the link is likely to be minimal if it does exist. Studies previously cited in the news suggested that Type A blood could be associated with higher risks of severe cases of COVID-19, and reporting included studies that had not yet been assessed by scientific experts (referred to in science as the peer-review process). One of these recent studies had been peer-reviewed and published in the New England Journal of Medicine (NEJM); however it used genes to determine the blood type, which is a method that is not very accurate. The gene testing company, 23andMe, recently released the preprint of a study (awaiting peer-review and using a similar gene association method) that identifies a strong association between blood type and COVID-19 diagnosis. The study suggests that people with blood group O tested positive less often compared to people with other blood groups, under similar circumstances.
Two more recent studies from Columbia University and Massachusetts General Hospital in the U.S. found that blood type is not associated with risks of intubation or death from COVID-19, after adjusting for other factors. While scientists continue to learn more, age and underlying health conditions remain more significant risk factors for severe COVID-19 symptoms, and Type A blood is not thought to be a major risk factor at this time.
While some studies have suggested a potential risk reduction for people with Type O blood, not all the studies have been peer-reviewed and the use of blood donors as study participants can give the appearance of Type O being more protective than it is (Type O blood is over-represented in blood donors, compared to the general population). Type O blood does not mean immunity to COVID-19.
As of now, there is not enough evidence to indicate whether or not there may be some connection between blood type and COVID-19 risk, though the link is likely to be minimal if it does exist. Studies previously cited in the news suggested that Type A blood could be associated with higher risks of severe cases of COVID-19, and reporting included studies that had not yet been assessed by scientific experts (referred to in science as the peer-review process). One of these recent studies had been peer-reviewed and published in the New England Journal of Medicine (NEJM); however it used genes to determine the blood type, which is a method that is not very accurate. The gene testing company, 23andMe, recently released the preprint of a study (awaiting peer-review and using a similar gene association method) that identifies a strong association between blood type and COVID-19 diagnosis. The study suggests that people with blood group O tested positive less often compared to people with other blood groups, under similar circumstances.
Two more recent studies from Columbia University and Massachusetts General Hospital in the U.S. found that blood type is not associated with risks of intubation or death from COVID-19, after adjusting for other factors. While scientists continue to learn more, age and underlying health conditions remain more significant risk factors for severe COVID-19 symptoms, and Type A blood is not thought to be a major risk factor at this time.
While some studies have suggested a potential risk reduction for people with Type O blood, not all the studies have been peer-reviewed and the use of blood donors as study participants can give the appearance of Type O being more protective than it is (Type O blood is over-represented in blood donors, compared to the general population). Type O blood does not mean immunity to COVID-19.
Context and background
The media is now reporting on how more recent studies found that blood type is not linked to risks of intubation or death from COVID-19, after adjusting for other factors like age and gender identity. Furthermore, it is important to note that Type O blood does not mean immunity to COVID-19.
The media is now reporting on how more recent studies found that blood type is not linked to risks of intubation or death from COVID-19, after adjusting for other factors like age and gender identity. Furthermore, it is important to note that Type O blood does not mean immunity to COVID-19.
Resources
- Genes, Blood Type Tied to Risk of Severe COVID-19 (NIH)
- The ABO blood group locus and a chromosome 3 gene cluster associate with SARS-CoV-2 respiratory failure in an Italian-Spanish genome-wide association and analysis (medRxiv)
- Genes May Leave Some People More Vulnerable to Severe Covid-19 (NYT)
- Is there a relationship between blood type and covid-19 infection? (MIT Technology Review)
- Genomewide Association Study of Severe Covid-19 with Respiratory Failure (NEJM)
- Testing the association between blood type and COVID-19 infection, intubation, and death (medRxiv)
- Relationship between the ABO Blood Group and the COVID-19 Susceptibility (medRxiv)
- Blood type and outcomes in patients with COVID-19 (Annals of Hematology)
- COVID and Blood Type (Harvard Medical School)
- Trans-ethnic analysis reveals genetic and non-genetic associations with COVID-19 susceptibility and severity (medRxiv)
- Early research from 23andMe strengthens link between blood types and Covid-19 (Statnews)
- Genes, Blood Type Tied to Risk of Severe COVID-19 (NIH)
- The ABO blood group locus and a chromosome 3 gene cluster associate with SARS-CoV-2 respiratory failure in an Italian-Spanish genome-wide association and analysis (medRxiv)
- Genes May Leave Some People More Vulnerable to Severe Covid-19 (NYT)
- Is there a relationship between blood type and covid-19 infection? (MIT Technology Review)
- Genomewide Association Study of Severe Covid-19 with Respiratory Failure (NEJM)
- Testing the association between blood type and COVID-19 infection, intubation, and death (medRxiv)
- Relationship between the ABO Blood Group and the COVID-19 Susceptibility (medRxiv)
- Blood type and outcomes in patients with COVID-19 (Annals of Hematology)
- COVID and Blood Type (Harvard Medical School)
- Trans-ethnic analysis reveals genetic and non-genetic associations with COVID-19 susceptibility and severity (medRxiv)
- Early research from 23andMe strengthens link between blood types and Covid-19 (Statnews)
