https://jamanetwork.com/journals/jamanetworkopen/fullarticle/2797782

Prevalence and Correlates of Long COVID Symptoms Among US AdultS

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Findings  In this cross-sectional study of more than 16 000 individuals, 15% of US adults with a prior positive COVID-19 test reported current symptoms of long COVID. Those who completed a primary vaccination series prior to infection were less likely to report long COVID symptoms.

...long COVID is prevalent and associated with female gender and older age...