Viral Variants, Vaccinations, and Long Covid — New Insights

New infections with SARS-CoV-2 continue 4 years after the pandemic began, despite advances in vaccines, antiviral medications, and preventive measures. 1 Beyond the serious complications of Covid-19, the postviral syndrome known as postacute sequelae of SARS-CoV-2 infection (PASC), or “long Covid,” remains a major public health problem. 2 The prevalence of long Covid is estimated to be 6.9% among noninstitutionalized persons in the United States who were previously infected with SARS-CoV-2. 3 But defining the true incidence, underlying pathophysiology, full manifestations, and prognosis of long Covid continues to challenge patients who have been affected by PASC, as well as providers and investigators. In . . .