Prevalence of long COVID in the general adult population according to different definitions and sociodemographic and infection characteristics. A nationwide random sampling survey in France in autumn 2022

Long COVID has been recognized since early 2020, but its definition is not unanimous, which complicates epidemiological assessments. This study estimated the prevalence of long COVID based on several definitions and severity thresholds in the adult population of mainland France and examined variations according to sociodemographic and infection characteristics. A cross-sectional survey using random sampling was conducted in August–November 2022. Participants declaring SARS-CoV-2 infection were assessed for infection dates and context, post-COVID symptoms (from a list of 31, with onset time, daily functioning impact, and alternative diagnosis), and perceived long COVID. Long COVID prevalence was estimated according to the WHO, National Institute for Health and Care Excellence, United States National Centre for Health Statistics, and United Kingdom Office for National Statistics definitions. Of 10 615 participants, 5781 (54.5%) reported SARS-CoV-2 infection, with 123–759 (1.2–13.4%) having long COVID, depending on the definition. The prevalence of WHO post-COVID condition (PCC) was 4.0% (95% CI: 3.6–4.5) in the overall population and 8.0% (95% CI: 7.0–8.9) among infected individuals. Among the latter, the prevalence varied from 5.3% (men) to 14.9% (unemployed) and 18.6% (history of hospitalization for COVID-19). WHO-PCC overlapped poorly with other definitions (kappa ranging from 0.18 to 0.59) and perceived long COVID (reported in only 43% of WHO-PCC). Regardless of its definition, long COVID remains a significant burden in the French adult population that deserves surveillance, notably for forms that strongly impact daily activities. More standardized definitions will improve integrated surveillance of, and better research on, long COVID.