SARS-CoV-2 could be hiding out in different places in the body to contribute to long COVID, the Guardian reports.
It notes that a handful of studies have uncovered viral RNA or proteins in the blood or stool of people with long COVID, which is marked by fatigue, joint pain, and memory issues. One small study from Harvard University researchers posted to BioRxiv last week found that nearly two-thirds of individuals experiencing long COVID had detectable viral S1, spike, or N proteins in their blood. The Guardian adds that the team previously found viral proteins in stool samples and that researchers from Stanford University also reported finding viral proteins in stool from people months after they had COVID-19.
"The question is whether or not continued presence of the virus in the gut or elsewhere may kind of tickle the immune system, and cause there to be persistent symptoms," Stanford's Ami Bhatt tells the Guardian, noting she would like to see additional studies into such possible reservoirs and their potential contribution to disease. The Guardian adds that studies like US National Institutes of Health's Recover study are underway to look into this more deeply.