Giménez-Orenga, Karen, Pierquin, Justine, Brunel, Joanna et al. · Frontiers in immunology · 2022 · DOI
This study found that a dormant virus-like element called HERV-W, which exists naturally in our DNA, may reactivate and remain active long after COVID-19 infection has cleared in people with long COVID. The researchers also discovered that people with higher levels of certain immune proteins (antibodies) against SARS-CoV-2, especially IgE antibodies, tended to have worse physical function. These findings suggest that HERV-W activation and lingering antibody responses might help explain why some people develop long-lasting COVID symptoms.
Since ME/CFS and post-COVID-19 condition share clinical similarities and both may involve persistent viral activation mechanisms, understanding how dormant viral elements reactivate could reveal shared pathological pathways. Identifying biomarkers like HERV-W expression and IgE antibodies could enable better subtyping of patients and development of targeted treatments, potentially benefiting both post-COVID and ME/CFS populations. This work bridges virology and immunology to explain mechanisms underlying post-viral illnesses.
This study does not prove that HERV-W activation causes post-COVID symptoms—only that the two are associated; the direction of causality remains unclear. The cross-sectional design cannot establish whether HERV-W reactivation persists indefinitely or eventually resolves. The findings are specific to post-COVID-19 and cannot be directly applied to ME/CFS without independent replication in that population.
About the PEM badge: “PEM required” means post-exertional malaise was an explicit required diagnostic criterion for participant inclusion in this study — not that PEM was studied, observed, or discussed. Studies using criteria that do not require PEM (e.g. Fukuda, Oxford) are tagged “PEM not required”. How the atlas works →
Spotted an error in this entry? Report it →