long covid
Long COVID — formally designated post-acute sequelae of SARS-CoV-2 (PASC) — refers to persistent symptoms lasting 12 or more weeks after acute COVID-19 infection. An estimated 5–10% of people infected with SARS-CoV-2 develop long COVID, creating a global health burden of tens of millions of patients with persistent fatigue, cognitive impairment ("brain fog"), breathlessness, palpitations, post-exertional malaise, and autonomic dysfunction. The NIH has committed over $1.15 billion through the RECOVER Initiative to understand and treat long COVID.
Active trials through the RECOVER-VITAL platform test antiviral therapy (extended-course nirmatrelvir/ritonavir), antihistamines for mast cell activation syndrome-related symptoms, pacing and graded exercise rehabilitation, low-dose naltrexone for neuroinflammation, metformin (with early data suggesting benefit if started acutely), stellate ganglion block for autonomic symptoms, and SSRIs for dysautonomia. Biomarker studies investigate viral persistence, microbiome disruption, and autoantibody generation as mechanistic targets.
Long COVID trials typically require symptom onset ≥12 weeks after documented SARS-CoV-2 infection with persistent symptoms; conditions like myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) with viral trigger may also be eligible.