The role of tiny blood clots in long COVID

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The key role of microclots in the diagnosis and treatment of long Covid is discussed by scientist Resia Pretorius of Stellenbosch University.

MICHEL MARTIN,HOST:

We're going to look at one of the biggest medical mysteries of the coronaviruses. We're talking about long periods of time. Patients who have it report a wide range of symptoms that persist for weeks or months after they've recovered from an initial COVID infection. Those symptoms can include fatigue, brain fog, problems with breathing, and even hair loss. According to researchers at the University of Michigan, as many as 100 million people around the world have or have had long carbon dioxide emissions. Doctors don't know a lot about the condition.

That's where the next guest will come in. Resia Pretorius is a professor at the University of South Africa. She and her colleagues have been analyzing blood samples from long COVID patients. Many samples had something in common. Could these tiny blood clot help researchers better understand long COVID and possibly even develop ways to treat it? Professor Pretorius is with us now. Professor, greetings. Thank you so much for talking to us.

ReSIA PRETORIUS: Hello.

Your research suggests that microclots have a role to play in understanding long carbon dioxide. Can you tell us a little bit more about what they are and how that might explain some of the symptoms that long COVID patients experience, like fatigue and brain fog?

PRETORIUS: Yes. I think we should stop talking about long COVID and talk about acute COVID. We and others have noted that the clotting system is not functioning properly during COVID. The dilemma with long COVID is that the percentage of individuals who never really get over the presence of these clotting abnormality when they are not infective anymore is up to 30%. These clot are present during long time.

Do you know why these microclots are not breaking down like blood clot in healthy people?

There are various entrapped molecule that prevent the breakdown of the microclots in these individuals' blood. The body is trying very hard to break down these clot with normal processes, but the molecules in the microclots prevent them from breaking down.

If these microclots are in circulation, they can damage the vasculature and cause a failure of the coagulation system of oxygen to your cells. It can be linked to all of the symptoms that have been noted.

Do you think your research can help labs detect long COVID in patients' blood and help doctors diagnose it? One of the reasons I ask is that people don't believe people who have had long confession. They struggle with this sense of shame, which is almost as devastating for some people as the condition itself. Do you think that the work would help people with a diagnosis that they would accept, that regular people would accept or that employers would accept so that people don't feel that they're not good enough?

It is one of the major problems that millions of people suffer from daily. They are very sick. All of the blood tests that they do at a pathologist or their clinician will come back in the healthy levels. Many clinicians say that these individuals are suffering from psychological issues. That is a big dilemma.

The disease does not exist because we do not yet have a easy, available diagnostic marker. One of the most important factors is that. We and others in South Africa are working very hard to get a diagnostic where we can detect microclots in circulation. We can think about treatment regimes only when we have diagnostics.

Treatment is something that we would be interested in. Does your research show any possible ways to treat chronic bronchitis? Is there anything you can tell us about that?

One of the problems with any treatment, whether it's long COVID or acute COVID or any other condition, is that the general clinical fraternity only believes data from clinical trials. There are no clinical trials that are focused on long COVID. We are working with a group of researchers from the U.S.A. and the UK. We're trying to get trials to see if conditions work or not. That is the most important thing that needs to be done. We need funds and big infrastructure to be able to do clinical trials.

It's estimated that millions of people have or have had long carbon dioxide, so my next question is, "How many of you have had long carbon dioxide?" It seems logical that the number could rise because of this current surge fueled by this latest variant. The world's attention has been focused on vaccines and therapies after that. And rightly so. Do you think it's time for the world's kind of research, attention and resources to shift to long COVID?

Absolutely. The focus has been on keeping people out of the hospital. Our health care facilities have been under a lot of stress. Many of the long COVID patients are at home, so they are not seen or heard of. They are struggling on their own. If we don't focus our attention on research and turn it to these very, very ill patients, our economy will see the consequences and have a severe impact on our economies worldwide.

Resia Pretorius is a professor at the University of South Africa. We were able to reach her via the internet. Professor Pretorius, thank you for sharing your knowledge with us.

Thank you very much for asking, PretoriUS.

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