Your chances of having severe Covid-19 might be linked to your blood type, study finds

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hmmm…can anyone tell me my blood type? thanks. #freakingOut


Well nuts. Guess I’ll be avoiding crowds for quite some time yet then.


Blood type A-positive. I’m in a rural area of Oregon, so I’ve been okay for now. Very curious to see how this holds up with more tests and data.


Remember, as it’s on medRxiv it’s a preprint:

No peer review, no post-publication review, literally just a PDF with some words and figures in :slight_smile:

File in the “possibly interesting” file, but might need more evidence.


Yup, me too. Fat, old(ish), A+ blood type. I catch this thing I’m probably gonna die.


I am more than just suspect of this until peer review and publication in a decent impact journal.

There is a lot of blood type hokum around, especially in asia.


A doctor can. Also any of those online genetics tests. If you’re looking for a free method, donating blood will also tell you.


Yep - the study only included about ~1600 COVID patients, which sounds like a lot but may not be that many given there are four blood types (8 if you consider rhesus factor), the patients all came from a relatively small area (Italy and Spain) and the fact they looked at over 8 million SNPs - you’re bound to find some correlations there. Also, based on the abstract, it doesn’t account for people who never developed symptoms and didn’t get tested (they did have a control group from the general population)

I only read the abstract, but my question is really why would blood type be associated with increased respiratory failure in the case of Covid 19? Without some kind of reason to think the A blood group would be associated with respiratory failure, it feels a bit like a fishing expedition.

There was also a stronger association with a gene encoding an enzyme (angiotensin converting enzyme 2) that is involved with controlling blood pressure - this would have a much more obvious link to respiratory failure, but it wasn’t emphasized in the headline or the manuscript’s title.

(The study also suggests the O blood group gets a protective effect)


I’m glad I read down the thread before I replied.

These days, I bet you even get a free virus test.


I have always joked that my blood type reflected my attitude: “B negative.”

Maybe the fact that I’m "B - " is a positive!

(I have actually been wondering if blood type played a role in disease severity. The idea came about from a relative expounding the benefits of the “Blood Type Diet”-- which I found ridiculous, since scientists still aren’t sure why blood types exist-- and the fact that clotting is one of the more dangerous symptoms. There does seem to be some evolutionary evidence that blood types are linked to disease resistance, including malaria.)


Are there any other diseases affected by blood type? This sounds unlikely

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B+ here. Had a crazy lung issue back in mid January. Couldn’t breath, super high fever, went to the hospital and they did a thoracotomy to drain septic fluid out of my lungs. Intubated and in a coma for 2 weeks. Antibiotics didn’t work, and docs were scratching their heads about WTF is going on. Thank goodness there were ventilators available. Maybe not so much now.

This was before they realized Covid-19 was prolific so I wasn’t tested. I don’t know if I had it or not, but losing a month of your life really sucks.


Thanks, good info.

I’ve actually had a history of lung problems, so I’m probably not safer than anyone else-- susceptibility to bronchitis and pneumonia, auto-immune issue relating to my lungs.


Are…are we twins?




i was more hoping someone here could just tell me…to avoid going to the germy places…you know, everywhere. (remembering to include the /s tag this time)


That’s what I thought when I read this other pre-print posted March 19, n=2173 patients in Shenzen and Wuhan. It also found type A to be most risky and type O less. I wondered about the woo factor, and about potential ethnic confounds (if, say, migrant workers living in dorms might be more likely to have type A blood). But this new pre-print reports essentially the same signal in Spanish and Italian populations, and that really increases my level of confidence in it.


Mine’s either AB+ or AB- (I will have to track down my dog tags to check). Until more research is done, I’ll do my best to not worry. More than I already am. Which it too much, to be honest.


ABO type is believed to affect susceptibility to noroviruses, smallpox, and malaria, among others. It has to do with proteins binding to the ABO protein markers, so it’s not as ridiculous as, say, the common beliefs that you should eat a certain diet or choose a certain career because of your blood type. That’s one of the theories for why humans have different blood types-- it may make it easier to achieve herd immunity if you don’t share the same blood proteins as all your neighbors. And we do know that the novel coronavirus causes clotting problems; it’s affecting blood or blood vessels somehow.