How likely are you to catch a long COVID?

First, science is cumulative.

Imagine that the “true number” of the long risk of COVID is the red bullseye, professor Alexandra Martiniuk, an epidemiologist at the University of Sydney. Each attempt to measure that number is like throwing darts.

“When the study begins, they are everywhere and the arrows land on the bushes,” she says. Eventually, the research issue will be fixed and more people will be included. “And over time, you get closer to the truth.”

Problem 2: Scientists have not yet fully agreed with the long definition of COVID. This is partly because the presentations vary greatly from person to person (one study included). 115 different symptoms).

Problem 3: There is no consensus among studies on the “length” of COVID. Is it a symptom that lasts for 2 weeks? Moon? one year?

Problem 4: Many studies require people to self-report their symptoms rather than measure them objectively. Some people are less likely to notice and report symptoms than others – think that your moody old uncle never refused to go to the doctor.

And the last big problem is the lack of control. Without it, it is not possible to determine whether the persistent symptoms are due to COVID or something else. “Some people say they’re tired when they investigate someone,” says Bette Liu, an epidemiologist at the University of New South Wales.

A perfect study of long COVID by Martiniuk looks like this: Randomly select thousands of people who have never experienced COVID and track them over the years. Next, compare those who have a longer COVID with those who are infected with the virus. please do not You will have long-term symptoms, you will be done, and you will be able to resolve the real risks.

Three years and a bunch of new varieties to pandemics, such research is no longer possible. So our data is inevitably incomplete and it’s hard to tell if we’ve really hit the Bullseye.

Let’s go back to the Lancet Estimated 5% prevalence in the area, This is pervasive in many media reports. Its estimates are based on self-reported symptoms and there is no control group. Therefore, “it is reasonable to conclude that the” actual “prevalence in the population can be much lower,” said Liu, the first author of this study.

Research that makes the news media enthusiastic Nature We will try to solve many of these problems. Three months after being infected with COVID, we concluded that 4.9% of people reported at least three symptoms, compared to 4% of those who had never been infected.

“I think,” says Martiniuk. “I think we are far from the Bullseye.”

One illness or some?

There is another potential problem. What if I haven’t looked at one condition?

The wide variety of symptoms reported suggests that multiple different disease processes may be in progress, says Martiniuk. This may explain why different studies come to different conclusions: they are actually investigating different illnesses.

“Looking at the prevalence of pancreatic cancer doesn’t try to understand the prevalence of breast cancer,” she says.

It also seems at least plausible that some of the long COVIDs are actually recovering from a nasty illness.

COVID can do terrible damage to us. So that cure is possible. Intensive care units are generally not the place you want to be. Patients in the ICU lose a lot of muscle. Their lungs need to recover from the machine breathing for them. Many people are psychologically damaged. About 25 percent of ICU patients – this is No COVID -According to “Post-intensive Care Syndrome” One quote.

Think now This large study Published in peer-reviewed medical journals PLOS medicine.. It was found that 73.2% of people receiving intensive care for COVID ended up with long COVID.

“A somewhat long COVID is what we expect from someone who has been hospitalized in the ICU,” said Gideon Maerowitzkats, an epidemiologist at the University of Wollongong.

Where do all of this land us? To be honest, I’m not sure.

All the experts we talked to were leaning towards lower true rates rather than higher ones, but there were no estimates that we thought were very accurate.

At this stage, the true risk of long COVID still seems to be a pandemic mystery.

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