Long COVID in Kids: What Happens When Coronavirus Symptoms Linger for Weeks or Months

COVID-19 cases have been steadily rising in children, sounding the alarm for parents across the country. Most kids develop mild symptoms that subside in a couple of weeks, but some suffer severe illnesses that can result in hospitalization or (rarely) death. A handful get "long COVID" that lasts for weeks or months after infection with the virus—a phenomenon also known as post-COVID conditions, post-acute COVID-19, or long-haul COVID.

According to the Centers for Disease Control and Prevention (CDC), "post-COVID conditions are a wide range of new, returning, or ongoing health problems people can experience four or more weeks after first being infected with the virus that causes COVID-19." The organization says that even patients with mild or asymptotic infection can get long COVID, which can trigger symptoms ranging from chronic cough to fatigue to anxiety.  

How common is long COVD in children, and what are the telltale signs? Also, how long do these lingering symptoms stick around? Consider this your need-to-know guide. 

Long COVID isn't common in children and adolescents, but it has been detected on rare occasions, explains Zachary Hoy, M.D., pediatric infectious disease specialist at Nashville Pediatric Infectious Disease, part of the Pediatrix Medical Group family of practices. 

It's hard to quantify exactly how often the condition occurs—partly because there's no clear definition for it, according to a November 2021 article from Yale Medicine. Statistics tend to vary based on different locations and studies.

The American Academy of Pediatrics (AAP) cites one study that said up to 52 percent of people between ages 16 and 32 have lingering symptoms 6 months after infection with COVID-19. And "the United Kingdom Office for National Statistics estimated that 12.9 percent of children 2 to 11 years of age and 14.5 percent of children 12 to 16 years of age still experienced symptoms 5 weeks after infection," says the organization. 

It's unclear what factors cause long COVID in kids. Research has shown that severe primary illness doesn't increase your chances of post-COVID conditions—and neither does having a compromised immune system, says Preeti Parikh, M.D. and Medical Director at GoodRx.

Studies are currently underway to understand the phenomenon. Several institutions, such as Yale Medicine, have developed specific clinics to evaluate patients, says Dr. Hoy. That said, the AAP says it will likely be several years before we know much about the causes of long COVID in adults and children.

The symptoms of long COVID are different for everyone. "Some children experience fatigue, difficulty playing team sports they were previously able to easily participate in, brain fog, or trouble focusing," explains Dr. Hoy. "Sometimes kids have weird symptoms that they tell their parents about—such as 'I feel weird'—or they don't seem to enjoy activities they used to pre-COVID."

Additionally, Dr. Hoy says long COVID symptoms in kids can overlap with those in adults, but they may have a harder time describing them.

Here are some of the most common signs of long COVID, according to the CDC and AAP:

Some children also have mental or neurological symptoms of long COVID, such as depression, hyperactivity, aggression, and anxiety, adds Dr. Hoy. 

Rarely, young people can develop multisystem inflammatory syndrome in children (MIS-C) during or after COVID-19 infection. This mysterious condition causes inflammation of different body parts, including the lungs, heart, lungs, brain, kidneys, eyes, skin, or gastrointestinal organs. MIS-C can lead to post-COVID conditions, and it can be deadly in extreme conditions. It's most commonly seen in kids 8 to 12 years old, says Dr. Hoy.

RELATED: 5 Things Parents Need to Know About Multisystem Inflammatory Syndrome in Children

Long COVID is a new phenomenon, and it's currently diagnosed through an evaluation of symptoms. "Usually, one's symptoms from COVID should be resolved within three to four weeks of onset, so if symptoms persist past four weeks then we start thinking about long COVID," explains Dr. Parikh.

Treatment is also determined based on symptoms, whether they're physical, neurological, or mental. Children are often referred to a speciality doctor like a neurologist, cardiologist, rheumatologist, or psychologist. "Unfortunately, we don't know how long these symptoms will last," says Dr. Parikh. "We have a lot to learn still since it is a new illness, so research is critical."

No matter how post-COVID conditions present, children might struggle with a diagnosis. "Treatment can involve talking to therapists or specialists about anxiety that children can have after dealing with COVID illness," says Dr. Hoy. "Children may be frustrated if they can't get back into their normal routines after COVID, such as getting back to sports, dance, or other extracurricular activities if they're more fatigued. But we're going to continue to learn more about these long COVID or post-COVID syndromes as we continue to see cases."

At the end of the day, parents should listen to their kids and seek expert advice for any concerns. "It can be difficult, but often listening to patients describe their symptoms and letting them know that other children and adults can have similar symptoms after COVID can help them," says Dr. Hoy.

The best way to prevent long COVID is following pandemic health protocols to ward off infection. Everyone ages 5 and up should get vaccinated—and all eligible adults should receive the COVID-19 booster shot. It's also important to wear masks in public indoor places, practice social distancing, wash your hands often, and avoid close contact with sick individuals.