Through a collaboration among investigators from Brigham and Women’s Hospital and Massachusetts General Hospital, researchers have identified a potential marker that may help inform diagnosis and treatment of long COVID. Investigators analyzed 63 plasma samples from patients with post-acute sequalae of COVID-19 (PASC also known as long COVID). In a preprint paper posted on medRxiv ahead of peer-review publication, the authors describe the detection of the SARS-CoV-2 spike protein circulating in the blood up to 12 months after diagnosis of active infection. The team detected the protein in more than half of the patient samples assessed. The findings suggest that the virus may persist in the body, lingering in an unknown viral reservoir. In a previous study of children with multi-system inflammatory syndrome, the researchers found a reservoir in the gastrointestinal tract. Those findings led to a clinical trial for a new treatment for MIS-C.
“If PASC is the result of persistent viral replication in tissues outside the lung, it may help explain why patients experience the symptoms of long COVID,” said senior author David Walt, PhD, of the Department of Pathology at the Brigham and senior author of preprint in MedRxiv. Walt's team leveraged samples provided by MGH colleagues. “Identifying this biomarker in the blood gives us a handhold on this condition, gives us a potential therapeutic target, and may help us identify people with long COVID who are most likely to benefit from new treatment approaches.”