The hunt for long COVID answers zeroes in on causes
Add Axios as your preferred source to
see more of our stories on Google.
Illustration: Sarah Grillo/Axios
Researchers are getting closer to understanding the underlying causes of long COVID and potential ways to definitively test for it.
Why it matters: That would be a massive step toward unlocking a complex condition that's debilitated millions of Americans, mystified scientists and frustrated patient advocates who feel their struggles have been ignored.
The big picture: The trickiest part of long COVID is the collection of different biological mechanisms believed to be driving a range of lingering symptoms, such as cognitive difficulty, fatigue and breathing problems, among others.
- Ultimately, doctors will need multiple ways to diagnose and treat patients.
Between the lines: There are some more established theories of what's causing the condition, including the idea that the coronavirus has found a way to persist in the body by hiding in viral reservoirs.
- Other possibilities: COVID-19 causes some people's immune systems to malfunction, reactivates herpes viruses that linger in most people, or causes inflammation in the lining of the blood vessels, experts said.
- Researchers probing those theories are studying antivirals Paxlovid and Valtrex and the substance use disorder medication naltrexone, which can reduce inflammation.
Where things stand: There still aren't diagnostic tests for long COVID, but they likely aren't too far off, said George Diaz, chief of medicine at Providence Regional Medical Center, who treated the first confirmed U.S. case of COVID.
- Some researchers are studying potential biomarkers in long COVID patients that could help better target treatments, including serotonin reduction, iron levels and high levels of a particular protein in blood.
- For instance, doctors at Children's National Hospital are using certain lab tests, such as those to determine cortisol levels or detect certain antibodies, to make diagnoses, said Alexandra Yonts, director of the hospital's long COVID program.
- "We've learned a tremendous amount if you look at the sheer volume of information that we've gleaned," Yonts said.
- "We have strategies for management ... the things you need to do on a day-to-day basis to function, even if that means not being able to do everything that you want to do," Yonts said. "And we have labs that can help us right now at least go in a certain direction towards treatment."
Reality check: Most treatments being studied focus more on managing symptoms rather than curing long COVID.
- The National Institutes of Health's RECOVER Initiative, created to study long COVID, this past week announced the start of mid-stage trials testing three treatments in patients who've experienced symptoms such as fast heart rate, dizziness and fatigue.
- Other RECOVER trials have tested therapies for viral persistence and brain fog.
The bottom line: With such a complex condition, researchers warn, it could still be a long road to finding definitive answers, and there likely won't ever be a silver bullet.
- But they said important advancements are already being made that could eventually help not only long COVID patients but also those with similar post-viral conditions.
