Exactly How Many People Have Long Covid?

Before the pandemic, Lyth Hishmeh—a 26-year-old living in Camberley, England—was always looking for something to keep himself busy. He was working as a software engineer and doing research into AI on the side while making plans to start a new company. He was juggling four to five textbooks at once. “I could not sit still,” he says. 

All that came to a halt on March 13, 2020, when he was sent home from work with a suspected case of Covid-19. His symptoms were mild but familiar: a cough, fever, shortness of breath. Within two weeks, they had subsided, and so Hishmeh went to buy groceries. At the shop, his heart began racing; he felt dizzy and out of breath. “It felt like some sort of heart attack.” He ignored it and boarded the bus home. But the same feeling came back again, this time worse. He stopped the bus, got off, and flagged down a police car before falling to the ground. He was brought to the hospital, where he had an ultrasound, which indicated Covid-19 pneumonia. The consultant said he was fine, and he was discharged. 

But Hishmeh wasn’t fine. Over the next few months, he developed all the strange and debilitating symptoms that have come to characterize the condition known as long Covid: brain fog, severe fatigue, heart palpitations. Just going to the bathroom was a struggle. Hishmeh was housebound for months, until October 2020. In the worst days of his long Covid, he couldn’t even watch a film all the way through. He went to the emergency room more than 10 times. “I would cry and beg, ‘Just fix me—do something,’” he says. 

Today, 16 months after being infected, Hishmeh can leave the house, but he still isn’t fully recovered. He hasn’t been able to return to work, and he has new food allergies. He also has postural tachycardia syndrome, where his heart races when he stands up. “I’m nowhere near fully recovered,” he says. “It was so awful that where I am now is a huge improvement. But where I am now to a normal person would probably be the end of the world.” 

Hishmeh is one of the estimated millions of people around the world who have long Covid. They’re stuck in a life-limiting limbo while scientists scramble to understand the mysterious condition. But as long Covid patients like Hishmeh continue to struggle with their illness, health authorities are struggling with some of the most basic questions about long Covid.  

To get a grasp on how big a problem long Covid is, we need to know how many people out there are stuck in situations like Hishmeh’s. That number is surprisingly difficult to pin down. The figures mentioned in the media vary wildly, depending on which study is cited. So what is the real figure?

Some estimates have ranged on the more conservative side. One data set, collected as part of the Covid Symptom Study using the app ZOE Covid from researchers at King’s College London, took a survey of 4 million people between March 25, 2020, and June 30, 2020. The results indicated that 4.5 percent of people with Covid-19 reported symptoms after 8 weeks, and only 2.3 percent of people after 12 weeks—a pretty low estimate. However, the study has faced criticism from long Covid sufferers and researchers alike. There are a few reasons why this estimate might be on the low side. First, the study most likely missed out on a number of long Covid sufferers who were too fatigued to log all their symptoms on the app on a regular basis. Also, if the patient had fewer than five symptoms on the last day they used the app, it counted them as recovered.