Long COVID: how many are suffering?

We’re looking at long COVID - long term symptoms that some people describe in the aftermath of an acute covid infection. They include breathlessness and extreme fatigue, heart problems, cognitive issues, diabetes and some people have developed neurological syndromes. What are the latest numbers on who is getting long COVID, and what are the most common symptoms? It turns out that’s a pretty complicated question, with multiple concurrent surveys using different methods leading to different numbers. Lawrence Young from the University of Warwick spoke with Eva Higginbotham...

Lawrence - Well it looks like from different studies now it's around a million people in total, including adults and youngsters. So as you said, this is complicated because the diagnosis is still a little vague in pinning down exactly the different types of long COVID, but it looks like something like 10 to 30% of adults can end up with this disease.

Eva - It's such an incredibly high number. How are those numbers being acquired? How are we measuring how many people?

Lawrence - Well, there are lots of different studies going on. There's a study, the REACT study that we hear about, which has looked at the prevalence of infection and long-term consequences. There are studies using the ZOE app, which is where people are self-reporting, those are often complicated because obviously that could be a bit biased if you're self-reporting. And then we have the Office of National Statistics data. So there's lots of different data coming in. And that's why we have such a broad range of percentages here, because we're still not exactly sure how best to define long COVID and therefore how many people are suffering, but it's clearly a lot of people.

Eva - And what do those data say about who is most likely to suffer from long COVID?

Lawrence - Well, whilst a lot of this suggests that you don't need to be symptomatic, you don't need to be really sick to develop long COVID, it's quite clear that if you experience five symptoms or more during the first week in which you're sick, then you're more likely to get long COVID. It is associated with increasing age, it's associated with obesity, with body mass index, and it's interestingly found more commonly in women than in men.

Eva - And what are the most common symptoms of long COVID? Is it often sort of a continuation of what you had in the acute phase or are people developing symptoms that they never had before?

Lawrence - Yeah, I think some of it is a continuation and there is a category of long COVID, which clearly is defined by continuing symptoms from the symptoms that you develop during the acute phase. But most of this is stuff that just lingers and it actually fluctuates a lot too. So it's defined by extreme tiredness and fatigue, shortness of breath, chest pain, joint pain, this thing called brain fog, which seems to be a very common feature of long COVID where you have problems with memory and concentration, insomnia, heart palpitations. So I think this is a range of symptoms, which makes defining long COVID quite challenging.

Eva - And of course we're still going through it. People like Freya are still sick 16 months later, but do we have any idea of how long most people might experience long COVID for? How long does it last?

Lawrence - Well, that's something where, again, the data is looking quite interesting. The data from the Office of National Statistics, which estimated about a million people were reporting COVID symptoms for more than four weeks also found that something like 385,000 folk had COVID19 for at least a year. And that's the data that came through in June of this year. So it's likely that quite a significant number of people will be having one or more of these symptoms for a long time.

Eva - And what about other viral infections? Cause we hear things like chronic fatigue syndrome; that can be set off by things like glandular fever as far as I'm aware. Is this really special to COVID or is there something more general to other viral infections too?

Lawrence - I think there is an element of something that is common in sort of post viral syndromes. And this is where I think it gets very complicated in terms of diagnosis, because - I think - it's quite clear that we're not looking at a single disease. We're probably looking at multiple diseases. Some of them associated with the severe infection and lung problems that people have if they've sadly had to go into intensive care, but a lot of the fatigue related illness, it's very reminiscent of chronic fatigue syndrome. And so I think we and others are looking at that in detail to see whether or not there is something very specific about SARS-CoV-2, or whether this is a general feature that we see with chronic fatigue.