Viral Reactivation During Acute COVID-19 and Long COVID

In a US longitudinal multi-omic study of 1,154 hospitalized patients with COVID-19 from the IMPACC cohort, significant reactivation of Herpesviridae and Anelloviridae was common during acute COVID-19, with virus-specific temporal patterns and associations with disease severity, host immune responses, and clinical outcomes. Chronic viral infections are ubiquitous in humans, and viruses that remain latent can reactivate during physiological stress, including severe illness; although SARS-CoV-2 infection has previously been linked to reactivation of viruses such as Epstein–Barr virus (EBV) and cytomegalovirus (CMV), the extent and immunological impact of this process have remained unclear. The study found that viral reactivation occurred frequently even in immunocompetent individuals with severe COVID-19 and was associated with increased systemic inflammation, challenging the prevailing view that chronic viral reactivation is primarily a consequence of immunosuppression. Importantly, viral reactivation persisted into convalescence, and Anelloviridae reactivation was associated with long COVID. Although the findings do not establish that viral reactivation causes worse clinical outcomes, the identified immune, transcriptomic, and metabolomic signatures provide potential biomarkers that may help improve prognostication and guide future strategies for treating acute COVID-19 and long COVID. Source: https://www.nature.com/