Excess of infection with SARS-CoV-2 during the first versus second wave of the COVID-19 pandemic among patients with long COVID

Post-COVID-19 condition affects up to 10% of patients months after a COVID-19 episode. Population-based epidemiology suggests that self-reported long COVID in France might be more common among those infected during the first wave of the pandemic than the second one, supporting the role of contextual risk factors in symptom persistence in some patients. We aimed to examine whether this pattern could also be observed in a clinical setting, considering patients with well-characterized post-COVID-19 condition and the general population. In a case-population study, we compared the rate of SARS-CoV-2 infection during the first wave (January 1 to May 11, 2020) versus the second wave, which involved the same historical variant (May 12, 2020 to January 15, 2021) between patients with post-COVID-19 condition assessed during a multidisciplinary day-hospital program and the general population. Binary logistic regression was used to compute odds ratio (OR) and 95% confidence interval (CI) for infection during the first versus the second wave. Among 177 consecutive patients, the odds of reporting SARS-CoV-2 infection during the first versus the second wave were significantly higher than in the Paris area general population (OR [95% CI]: 1.74 [1.27–2.40]), p < 0.001). The results remained similar in sensitivity analyses considering the French general population (1.36 [1.02–1.88]). These results further suggest the role of contextual factors in long COVID and the relevance of a biopsychosocial perspective. - Patients with post-COVID-19 condition were assessed during a multidisciplinary day-hospital program. - Infection was more frequent during first versus second wave compared to the general population. - These results replicate and extend previous findings from a non-clinical population. - Contextual factors may play a role in persistent symptoms after COVID-19.