What We Know About Long-Term COVID-19

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For months, we’ve primarily been told of three dominant outcomes for those infected with COVID-19: Some people die (particularly in the case of older patients and those with underlying health problems), some people experience something like a bad flu, and some people don’t notice they’re infected at all. But for some, the coronavirus is neither lethal nor mild, with illness lasting far longer than the average 11.5 days. This group has referred to themselves as COVID-19 “long-haulers,” and their reported symptoms are wide-ranging and occasionally invisible, complicating the diagnosis and treatment of an already confounding disease. Thousands of these long-haulers report still feeling sick months after first falling ill.

Here is everything we know about long-term COVID-19 so far.

What are the symptoms of long-term COVID-19?

Many people with long-term COVID-19 report a protracted duration of well-known symptoms like a dry cough, chest tightness, headaches, and fatigue. Others have reported a near-full recovery, but report persistent problems with taste and smell, also known as “anosmia.” (Most people who get COVID-19 and experience loss of taste and/or smell will regain these senses within a few weeks.)

For other self-described long-haulers, symptoms are unpredictable, and may continue to develop weeks or months after initial sickness. These may include brain fog and disjointed thinking, numbness in the legs or arms, extreme lack of energy, and ringing in the ears. Some of those with long-term COVID-19 symptoms have experienced heart complications, though it’s important to note that most people in that group had preexisting conditions (typically diabetes or hypertension).

Just how long is long-term COVID-19?

It remains unclear how long people with long-term COVID-19 will, on average, feel sick. We know, though, that there are people who fell sick in March and are still sick five months later. Further complicating the timeline is the fact that not all long-haulers have received positive coronavirus tests, and some, after receiving an initial positive, have since tested negative — but still feel sick. Despite well-known issues with the tests’ accuracy, these confusing test results have contributed to what many long-haulers characterize as pervasive dismissiveness from doctors regarding their symptoms; many people with long-term COVID-19 report having been told by doctors that what they’re experiencing is actually anxiety.

Is anyone more at-risk for long-term COVID-19?

So far, there is no clear picture as to who might experience long-lasting coronavirus symptoms. Patients include women, men, older and younger people, and children. Some of these patients had underlying and/or chronic health conditions, but many say that they were completely healthy prior to contracting COVID-19.

The CDC states that “prolonged symptom duration and disability” are most common in adults who’ve been hospitalized with severe COVID-19, but acknowledges that long-lasting illness presents in younger patients as well, citing other health conditions (both physical and mental) as risk factors for prolonged illness in those groups.

What causes long-term COVID-19?

Doctors don’t yet understand every factor which contributes to patients’ COVID-19 outcomes — why, for instance, some older patients remain asymptomatic, and why some younger, healthy patients experience fatigue months after infection. Individuals’ response to COVID-19 likely has much to do with the way their immune system reacts to initial infection. In some patients, the body produces a reaction called a “cytokine storm,” or an overproduction of immune cells, which can result in lung inflammation, fluid buildup, and pneumonia. Still, it’s unclear why this happens to certain patients and not others.

These are questions being investigated at a number of new clinics studying long-term and “post-COVID” illness, including Penn’s Post-COVID Recovery Clinic and the Center for Post-COVID Care at Mt. Sinai in New York.

What We Know About Long-Term COVID-19