Blood Type May Influence How Prone You Are to the Coronavirus, Report Says

Coronavirus Study hasn’t been peer-reviewed, but there’s plenty of evidence for correlations between blood type and susceptibility to everything from malaria to cancer

Blood test tube for analysis. 2019-nCoV virus infection originating in Wuhan, China
FabrikaSimf / Shutterstock.com

People with type A blood are more prone to contracting COVID-19 and are likelier to be hit harder than people with other types of blood. Type-O people are less likely to get COVID-19 and suffer less when they do get it, reported a large Chinese team headed by Jiao Zhao of the Shenzhen School of Medicine.

Their report appeared last week in the pre-publication site medRxiv.

Haaretz Weekly Ep. 71: A tale of two crises: Coronavirus vs. Constitution

Most people don't know their blood type, it seems, based on the unscientific method of asking friends and those passing by the window. They probably also don't know that our blood type affects our susceptibility to some diseases – including, possibly, coronavirus.

Mark you: Anybody can get COVID-19, including newborns and toddlers, the hale and hearty, and a hale, hearty, blood-type-O teenager. Type A blood won't doom you and type O won't necessarily save you. But knowing about probabilities can be helpful.

The paper by the Chinese team, which included statisticians, has yet to undergo peer scrutiny. Because of the gravity of the coronavirus crisis, some scientific studies relating to the germ SARS-CoV-2 and to COVID-19 – the disease it causes – are being “pre-published” hot off the printer, before the crucial but glacial process of peer review.  

The acceleration in publication has meant, among other things, that there is a tsunami of papers on this particular coronavirus and the disease it causes: More than 24,000 have been published so far, both peer-reviewed and in pre-publish sites like bioRxiv and medRxiv, according to the MIT Technology Review.

This flood can bring new discoveries to the world's attention, even though this unprecedented practice can lead to the dissemination of mistakes. If a paper does get something wrong, correction (and/or retraction) can quickly ensue. For instance, in early February a paper claimed to have found “uncanny” similarities between SARS-CoV-2 and the HIV virus. That led to speculation that the virus had been engineered by evildoers. The paper was quickly debunked and withdrawn.

Now we have this paper about blood types, but in contrast to drivel hinting at malicious agencies of infection, this could be helpful.

A Magen David Adom paramedic performing a coronavirus test exercise on a volunteer, February 26, 2020.
Jack Guez/AFP

The research was designed to investigate the correlation between blood type (ABO) and susceptibility to COVID-19 – and find it they did. Among other things, this knowledge could help health authorities prioritize the distribution and use of the all-precious personal protective equipment, which is in short supply almost worldwide.

How did Jiao et al reach their conclusion? They looked at 1,775 COVID-19 patients in Wuhan (including 206 who died) and compared them with 3,694 “normal” people in Wuhan (negative for coronavirus).

Among healthy Wuhanites, 32.2 percent had Type A blood, compared with 38 percent among COVID-19 sufferers. Ergo: The proportion of COVID-19 patients among people with type A was higher than in the “wild” population.

Blood types B and AB didn’t sway matters much either way.

But O-type blood also made a big difference: Among the sick, 25.8 percent had O-type, compared with 33.8 percent among the healthy.

The finding is not a huge shock, since science has long known that certain blood types confer more protection (or susceptibility) to certain diseases and conditions.

People with A, B, or AB blood types are more prone to heart disease and cognitive dementia than people with O type.

A 2017 paper published in PubMed found that O-group blood “may have some influence in protecting against blood transmitted infection.” People with A-blood are more prone to hepatitis B and AIDS, too. And that’s just one example.

Also, diseases and parasites may wipe out whole groups in the population whose blood type does not confer resistance, relatively speaking. Much research has been done on blood type and relative resistance or susceptibility to malaria, and the severity of the condition.

Again, people with O-type blood were found to be strongest in resisting the parasite and the disease, and people with A or B were the least resistant.

There is a theory that most Native Americans today have O-type blood because it confers relative resistance to syphilis, which decimated people with other blood types in the New World

Cigarette habits aside, blood type even affects our susceptibility to at least some cancers. Compared with blood type A, blood type B was associated with statistically significant reduced risk of all cancers, but not compared with O

Finally, no, a weight-loss diet based on blood type isn't a thing.

Now, getting back to the coronavirus, the best recommendations are: don't smoke; and adhere to the containment rules whatever your blood type. There is no information yet about people who have blood types other than ABO (they exist) and their susceptibility to the coronavirus.