COVID-19 awakens dormant viruses — and one is linked to long COVID

A new study published in Nature reveals that COVID-19 can reawaken dormant viruses in hospitalized patients, potentially contributing to long-term health issues. Researchers from Boston Children's Hospital and 14 other U.S. institutions analyzed genomic data from 1,154 patients across 20 medical centers. Of these, 11 viruses were found to have reactivated within 40 days of hospital admission.

The most common reactivated viruses were Epstein-Barr, herpes simplex 1, cytomegalovirus, and Anelloviridae. Among these, Anelloviridae, which typically remains dormant in about 90% of the population, showed a strong link to long COVID. This finding suggests a novel mechanism for long COVID, challenging the prevailing notion that chronic viral reactivation is mainly due to immunosuppression.

Emma Levy, MD, PhD, director of the Precision Vaccines Program at Boston Children's Hospital, emphasized the importance of these findings for improving diagnostics and treatments for long COVID. The study also uncovered an unexpected pattern where Epstein-Barr and cytomegalovirus became active in response to inflammation, rather than due to suppressed immunity.

The researchers plan to further investigate the immune system's response to these reactivated viruses during COVID-19 and explore potential treatments.