Dear Doctors: Is there anything new on long COVID? I have it, and it hijacked my life. I get tired really easily, can't exercise like I used to and my heart often beats too fast. The worst part is the brain fog, which affects my work. Is there any progress on a treatment or on determining what causes it?
Dear Reader: Your letter is one of many we continue to receive about long COVID. We hope our answer to you will be helpful to any other readers facing similar struggles.
Nearly four years since long COVID was first identified, most us are familiar with the condition. The term refers to the collection of symptoms that drag on after someone's initial bout of COVID-19 has ended. These often include the decline in stamina, changes to heartbeat and brain fog that you are experiencing. Also common are muscle and body aches, headache, difficulty breathing, an ongoing loss or diminishment of the sense of taste and of smell, gastrointestinal problems, extreme fatigue, insomnia, changes to cognition and depression.
The one thing all people with long COVID have in common is an initial SARS-CoV-2 infection. That's the coronavirus that causes the disease. Beyond that, it affects each person differently. At this time, more than 100 different symptoms and health problems have been documented in people diagnosed with the condition. And despite intensive study by researchers throughout the world, neither the cause of long COVID nor a specific treatment have been identified. Lacking that, doctors focus on managing each person's specific symptoms. Depending on the complexities of each case, this can involve specialists in the fields of neurology, cardiology, psychiatry, immunology, pulmonology and physical therapy.
Despite the lack of a definitive breakthrough, researchers are amassing a growing body of knowledge about long COVID. Several studies found that fragments of the SARS-CoV-2 virus can persist in the body long after an initial infection. This can cause ongoing inflammation and may contribute to some symptoms.
Another school of thought looks at long COVID as an autoimmune disease, in which the SARS-CoV-2 virus causes the body to attack its own tissues. A recent study highlights the potential role of immune cells known as monocytes, which alert other white blood cells to the presence of infection. It appears COVID infection can damage the structure of those immune cells, and thus scramble their behavior. There is also speculation that COVID infection may awaken existing viruses that had previously remained dormant in the body. These may include the Epstein-Barr virus, which has symptoms in common with long COVID. Each of these discoveries highlights potential avenues of treatment.
One thing has become clear: It is impossible to predict who will develop long COVID. Although a bit more common in those with severe COVID-19, it does occur in people who had a mild illness. It is now understood that Paxlovid, a medication effective in treating COVID-19, does not prevent long COVID. However, a new study links being vaccinated with a markedly lower risk of developing long COVID. This topic is firmly on our radar, and we will be back with updates as needed.
(Send your questions to askthedoctors@mednet.ucla.edu, or write: Ask the Doctors, c/o UCLA Health Sciences Media Relations, 10960 Wilshire Blvd., Suite 1955, Los Angeles, CA, 90024. Owing to the volume of mail, personal replies cannot be provided.)
