COVID-19 is still here and causing first, second or even third (and beyond) infections in people as the novel coronavirus continues to mutate into more contagious forms. But millions of people who got sick a long time ago have yet to see a full recovery. They live with long COVID or post-COVID conditions, umbrella terms for a variety of persisting health conditions and symptoms doctors don't fully understand. 

Severity of the condition varies, but the impact on quality of life has been so devastating for some that long COVID has been legally considered a disability in the United States since July 2021.

Research initiatives, some funded by the US government, have launched to help find definitive answers about risk factors, symptoms and possible treatments for long COVID. Because COVID-19 was a new virus, diagnosing and treating its lingering symptoms and health effects is uncharted water. Like other chronic diseases, people with long COVID are having a difficult time being diagnosed or even believed by their health care providers. 

"When COVID first came out, we didn't know anything about it," says Dr. Kathryn Boling, a primary care doctor with the Mercy Medical Center. "This virus is new to us, and it's done a lot of things that we haven't expected." 

By now, most Americans have had COVID-19 at least one time. (By the end of February 2022, more than half of people in the US had it... and this was before the current BA.5 wave.) Estimates of how many people have or will have long COVID vary, but the US Centers for Disease Control and Prevention in June found that nearly 1 in 5 people who have had COVID-19 developed long COVID. 

As people continue getting sick, long COVID will continue to be a public health problem even after COVID-19 eventually moves out of the pandemic phase.

Here's what we know (and don't know) about it. 

The many faces of long COVID 

The virus that causes COVID-19 disease, SARS-CoV-2, can infect virtually every system in the body and cause damage inside bodies. And the reasons for someone's long COVID can also change their symptom presentation. 

Dr. Devang Sanghavi is a critical care physician with the Mayo Clinic. He says there are a few ways COVID-19 can cause long COVID in people, and they may be broken down into different groups: People with severe-enough disease that they developed organ or cell damage; people who were hospitalized and have lingering health effects from that hospitalization; and people who weren't necessarily hospitalized (and may have had mild or no symptoms), but developed symptoms as a response to the acute phase of the virus.

The symptoms of the second group of people who have long COVID are similar to people hospitalized for other reasons in a phenomenon called post-intensive care syndrome. PICS can cause muscle weakness, cognitive problems (like brain fog) and mental health issues like anxiety, depression or symptoms of post-traumatic stress disorder following a person's time spent in a hospital bed.

But the last group, people who weren't hospitalized and may have only had a milder illness, has been the focus of research that has centered on the way our immune systems respond to COVID-19.

"That is where there is a lot of interplay between patients' immunity, the inflammatory marker, autonomic functions and just the basic body constitution that patient has," Sanghavi said.

Bryan Lau is an epidemiologist with the Johns Hopkins Bloomberg School of Public Health and co-lead of the Johns Hopkins COVID Long Study. He said one leading theory is someone's immune system can remain in a "heightened state" after COVID-19, which can lead to a variety of symptoms. (This may also explain the ongoing inflammation present in many long COVID patients, which might be a cause of brain fog.) Other theories include that, in some people, viral RNA might still be around infecting cells in the body and causing symptoms, or that COVID-19 causes tiny blood clots called microclots that can wreak havoc in different areas of the body. 

"My guess is that it isn't just one of these theories and that long COVID has several biological mechanisms," Lau said in an email. "This could explain why there are so many types of symptoms among people with long COVID as different mechanisms lead to different symptoms."

The struggle to get treatment

There's a trial starting in the United Kingdom that will study how well anti-inflammatory drugs, antihistamines and anti-clotting drugs work at treating or preventing long COVID. This builds off other reports that some people have found relief with over-the-counter antihistamines (allergy medication), anticoagulants (blood thinners) and other experimental regimens. 

Boling says she's had luck prescribing some of her patients Quercetin, an anti-inflammatory supplement that's found in apple peels, when they get sick with COVID-19. She also reports low numbers of patients with long COVID, which might be attributed to lower inflammation from the supplement. But "might," she says, "is the operative word." 

"We're still learning about this," Boling added. "So there's really no 'tried and true' that we can point to that works for everyone." Because each case is so individual, the symptoms vary widely and there are different causes for symptoms, each case of long COVID will need to be treated differently. Someone experiencing lasting symptoms from organ damage will need different care from someone who has blood clotting or an autoimmune response, for example. Finding a standard of care for long COVID, at this point in time, is difficult -- if not impossible.

But a treatment method used for one patient may be unhelpful, or even harmful, for another long COVID patient with a different root cause of the disease. 

"The last thing you want is to hurt the patient by doing something they may not benefit from," Sanghavi noted. 

Finding care and community

Long COVID is usually described as any new or persisting symptoms that appear (or linger) at least a month after initially contracting COVID-19. Getting good care when you have symptoms of long COVID can be difficult, and typical blood tests or X-rays may return normal -- a frustrating feeling that people with chronic fatigue syndrome, chronic Lyme and other historically misunderstood and underdiagnosed conditions can attest to. The CDC even has a list of tips for your doctor's appointment about long COVID, which include bringing a physical list of all of your concerns and asking for a visit summary. 

To have the best luck finding specialized and more comprehensive care for long COVID, Sanghavi says long COVID clinics dedicated to treating the illness are "the place to be." Most major hospital systems will have one -- the Cleveland Clinic's reCOVer Clinic is just one example -- but you can ask your doctor (or any health care professional, if you don't have a primary care doctor) for a clinic or support group in your area. Survivor Corps, an organization for people with long COVID, has a map of post-COVID care centers so you can find one in your state. According to Survivor Corps, all but two states (Kansas and South Dakota) have at least one specialty clinic. These centers are meant to offer people specific treatment for their illness by providing a team of health care providers with a variety of specialties.

Groups like Survivor Corps, which also has a Facebook page, provide educational resources and community support to people with long COVID, which can be pivotal for patients newly diagnosed with a new and poorly understood condition. Since 2020, patients have also shared information in a less formal way on social media with hashtags like #LongCovid; in fact, this hashtag is the origin of the condition's name. 

COVID groups have also drawn on the expertise of other disability communities who might've had firsthand experience negotiating with skeptical doctors or fighting for accommodations in daily life. People of color have also historically been mistreated or underserved in health care settings, bringing additional experience to the wider disability community. 

Unlike some disabilities, long COVID wasn't present at birth and may not be with someone for a lifetime. But the number of people now confronted with it adds to an existing conversation about what it means to live with a chronic condition or disability. 

"We're at this real confrontational moment of trying to educate as many people as possible about disability and structural inequalities and trying to make sure [long-haulers] get the resources they need right now," Mia Ives-Rublee, director of the Disability Justice Initiative at the Center for American Progress, told the Washington Post in a story about disability and long COVID.

Finding the blend of community and purposeful medical intervention could be the way forward for long COVID patients. 

"One message that I would like to send out to these patients is that their symptoms are real," Sanghavi said. "We may not have answers right now about why and how and what we can do to help them, but they should not be struggling and suffering alone." 

The information contained in this article is for educational and informational purposes only and is not intended as health or medical advice. Always consult a physician or other qualified health provider regarding any questions you may have about a medical condition or health objectives.