Post-viral fatigue syndrome (PVFS) refers to persistent, debilitating fatigue and systemic symptoms that continue weeks to months after an acute viral illness. It has gained renewed attention in the post-COVID era, but similar syndromes have long been described following infections such as EBV, influenza, dengue, and SARS-CoV-1. Clinically, patients report profound fatigue disproportionate to exertion, post-exertional malaise, cognitive dysfunction (“brain fog”), sleep disturbances, myalgia, and autonomic symptoms.
Emerging evidence suggests a multifactorial pathophysiology involving immune dysregulation, persistent low-grade inflammation, autonomic imbalance, mitochondrial dysfunction, endothelial injury, and possible viral antigen persistence. Elevated pro-inflammatory cytokines altered T-cell responses, and microvascular changes have been documented in subsets of patients. However,…
