Researchers studying cause, treatment for long COVID-19


Dear Doctors: When are treatments for long COVID going to be available? I had COVID-19 in the very beginning, when there were no tests for it yet, and I’ve never really recovered. Is long COVID still happening to people who are getting sick now?

Dear Reader: As many of you know by now, the term “long COVID” refers to the ongoing and often debilitating physical symptoms that continue for weeks or months after someone has recovered from an initial SARS-CoV-2 infection. Almost two years into the pandemic, close to 250 million people have been diagnosed with COVID-19 worldwide. Data shows that at least one-third and up to one-half of them are left with symptoms that linger up to at least six months. These include a prolonged loss of the sense of taste and smell, persistent cough, chest congestion, muscle aches, weakness, racing or pounding heart, difficulty concentrating and profound fatigue. A growing number of people with long COVID find themselves forced to curtail their daily activities or even quit their jobs because the collection of symptoms interferes with their ability to function. At the start of the pandemic, long COVID appeared to be an outlier. However, it is now a known part of the disease process.

It’s still not clear what causes long COVID. It affects people of all ages, including children, and occurs even in those whose initial disease was mild. A theory that was posed early on is that fragments of the virus may persist in the body, which triggers an immune response to fight off a threat that is no longer there. Another plausible idea is that SARS-CoV-2 infection leaves the immune system itself in disrepair, much like what happens in an autoimmune disease.

Elizabeth Ko, MD and Eve Glazier, MD

Most recently, scientists at Yale University and the University of California, San Francisco, have uncovered what they consider to be promising clues to what is going on. In studying the blood of patients with long COVID, the researchers have identified unusually high levels of compounds known as cytokines. These are small proteins secreted by certain immune cells whose main job is to regulate inflammation. Depending on the specific type -- there are proinflammatory and anti-inflammatory cytokines -- they play a role in either increasing or decreasing inflammation. The findings in patients with long COVID suggest the immune system is keeping their bodies in a state of chronic inflammation. The researchers’ blood analysis has also found unusual activity in key immune system “attack” cells, such as T-cells. This supports the scenario of lingering virus particles in the bodies of patients with long COVID.

While there is no known cure for long COVID at this time, intensive research is taking place. Scientists are looking into antiviral drugs to clear lingering virus or virus particles from the body. The use of immunosuppressant drugs to manage inflammation is also being explored. For now, though, treatment consists of a multidisciplinary approach to ease and manage each patient’s unique symptoms. This includes specialists in neurology, cardiology and pulmonology, as well as the emotional and mental health support that can help patients as they endure the long COVID marathon.

To learn more about the vaccines and for the latest information visit UCLA Health's COVID-19 Vaccine Info Hub.

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