How many people get ‘long COVID’ – and who is most at risk?

A few months ago, a young athletic guy came into my clinic where I’m an infectious disease physician and COVID-19 immunology researcher. He felt tired all the time, and, importantly to him, was having difficulty mountain biking. Three months earlier, he had tested positive for COVID-19. He is the kind of person you might expect to have a few days of mild symptoms before recovering fully. But when he walked into my clinic, he was still experiencing symptoms of COVID-19 and he could not mountain bike at the level he was able to before.

Tens of millions of Americans have been infected with and survived COVID-19. Thankfully, many survivors get back to normal health within two weeks of getting sick, but for some COVID-19 survivors – including my patient – symptoms can persist for months. These survivors are sometimes dubbed long-haulers, and the disease process is termed “long COVID” or post-acute COVID-19 syndrome. A long-hauler is anyone who has continued symptoms after an initial bout of COVID-19.

Numerous studies over the past few months have shown that about 1 in 3 people with COVID-19 will have symptoms that last longer than the typical two weeks. These symptoms affect not only people who were very sick and hospitalized with COVID-19, but also those with milder cases.

Many long-haulers experience the same symptoms they had during their initial fight with COVID-19, such as fatigue, cognitive impairment (or brain fog), difficulty breathing, headaches, difficulty exercising, depression, sleep difficulty and loss of the sense of taste or smell. In my experience, patients’ symptoms seem to be less severe than when they were initially sick.

Some long-haulers develop new symptoms as well. These can vary widely person to person, and there are reports of everything from hair loss to rapid heart rates to anxiety.

Despite persistent symptoms, SARS-CoV-2 – the virus itself – is not detectable in most long-haulers. And without an active infection, they can’t spread the virus to others.

Patients who were hospitalized for COVID-19 are the most likely to have persistent long-term symptoms.

In a study published in July 2020, Italian researchers followed 147 patients who had been hospitalized for COVID-19 and found that 87% still had symptoms 60 days after they were discharged from the hospital. A more recent study, published in January, found that 76% of hospitalized COVID-19 patients in Wuhan, China, were still experiencing symptoms six months after first getting sick. ...