Fair warning: If you are squeamish about blood, make sure you’re sitting down to read this, or just read another one of our (fantastic) COVID-19 blog posts.
Now that that’s out of the way …
Blood has many functions, including bringing oxygen and nutrients to your lungs and tissue, carrying cells that fight infection, and regulating body temperature. It plays a critical role in keeping your body up and running.
So, what role does it play in COVID-19?
While knowledge about COVID-19 is still developing, early evidence points to blood being a key player in understanding the virus.
The (Potential) Power Of Plasma
Blood is made up of many parts. About 45% of the blood is made up of red and white blood cells, and platelets. The other 55% is a liquid portion called plasma. Plasma has several roles, such as supplying proteins that are critical for immunity, supporting cell function, and helping maintain blood pressure.
Plasma also contains antibodies — proteins that you develop after being exposed to a disease so that the body can fight off the disease in the future.
Plasma Protection
If you have fully recovered from COVID-19, you (most likely) have COVID-19 antibodies. This doesn’t necessarily mean that you can never get the virus again. It’s still unclear how much or for how long antibodies can fight off another bout of COVID-19.
However, it does appear that people who have recovered from COVID-19 do have antibodies that offer some degree of protection. And that’s the basis behind plasma donation as a potential cure for the virus.
Researchers are currently studying if people with COVID-19 who have or are at risk for severe illness can benefit from a plasma donation. People who have fully recovered and have tested positive for antibodies donate plasma, which then gets transferred to a patient via an intravenous (IV) line.
It is too early and there have not been enough studies to say that plasma donation is a good treatment option. However, early findings have shown that patients have benefited from it.
Speaking Of Donations …
If you have had a confirmed case of COVID-19, as well as confirmed antibodies, you may be eligible to donate plasma.
If you have not had COVID-19, consider a normal blood donation. Blood banks have been running low since the start of the pandemic.
Source: The American National Red Cross
The Clotting Factor
When you get injured, your body forms clumps of blood called clots that stop excessive bleeding. But if your body makes too many clots or the clots form abnormally, they can block blood flow throughout the body. Clots can also travel to vital organs like the brain, heart, and lungs. In turn, this can lead to serious complications, such as heart attack, stroke, organ failure, or even death.
Clotting & Coronavirus
There have recently been reports of increased blood clots in patients who are hospitalized with COVID-19. It’s not yet clear if patients with mild cases who are at home are also experiencing clots, although there is suspicion that these patients are suffering from clots, too.
For the most part, people who are already at high risk for COVID-19 complications — such as males, older adults, or those who are obese — are more at risk for clots. However, there has been a concerning number of cases among the younger and otherwise healthy population — people who are not typically at high risk for complications.
The exact connection between COVID-19 and blood clots is not clear just yet. One hypothesis is that the virus sets off a reaction in the immune system that changes how certain parts of the blood function, resulting in increased clotting.
Also, people who are mostly sedentary — such as COVID-19 patients who are so sick that they are completely bed-bound — have a higher risk for blood clots.
Preventing Blood Clots During COVID-19
Even though anyone with COVID-19 can get blood clots, clots are notably more common in people with other risk factors. Keep yourself as healthy as possible — such as losing weight if you are obese or quitting smoking.
If you do get COVID-19 and are confined to your bed, try to get up to walk around if you are able. You may also want to try compression stockings, which are socks that improve circulation and reduce the risk of clots.
Blood Type May Make a Difference
Blood contains antigens, which are substances that trigger a response from the immune system. Your blood type is based on the presence or absence of certain antigens — called A and B antigens — and whether or not there is a protein called the Rh factor (+ or -) on the surface of your red blood cells. Depending on these characteristics, your blood may be categorized as A+, A-, B+, B-, O+, O-, AB+, or AB.
Blood type is genetic, meaning your type is the result of your parents’ types.
What Does Blood Type Have To Do With COVID-19?
Well…the answer isn’t quite so clear-cut.
Most people with COVID-19 do not experience severe illness. In fact, some researchers believe that about 40 to 45% of people who have the virus do not have any symptoms at all.
There are many reasons why some people may get more sick than others, from age to underlying medical conditions to personal behaviors like smoking. And based on early results from several studies, there was a theory that blood type could be a cause, too.
According to a June 2020 study, people with blood type A have a 50% greater risk of needing a ventilator or oxygen support if they have the virus. On the other hand, people with blood type O have about a 50% reduced risk of severe illness. The study also found that people with type A may have a greater risk of acquiring COVID-19 in the first place, while those with type O may have a lower risk of contracting it.
The Other Side
However, Harvard Medical School researchers found in a July 2020 study that might not be the case.
Their study did show that people with type O had a lower frequency of testing positive for the virus than people with other blood types, but it didn’t show that people with type A have a higher frequency. In fact, they found that people with types B or AB were more likely to test positive than people with type O.
When it came to the risk of severe illness — which they defined as requiring intubation or leading to death — they found no association with blood type.
The Harvard researchers concluded that blood type does not predict disease severity, and that people with types B or AB are the ones at higher risk of getting the disease — not those with type A.
The differences in conclusions between these two studies just confirms how much there is still to learn about COVID-19, and how quickly our understanding of it can change. It may still be too early to say definitively that blood type does play a role in disease severity or likelihood of contracting the virus, and, if it does, how it plays that role.
What Next?
When it comes to antibodies in plasma, clotting, and blood type in relation to COVID-19, all of our knowledge is in the early stages. We are gaining new knowledge every day, but it is still largely a mystery.
As the medical community continues to learn about COVID-19, the relationship between the virus and blood could reveal itself as a vital contribution to a vaccine or cure.
Until then, wear a mask.