Trends in Post-COVID-19 Condition by Pandemic Waves

Abstract

Background: COVID-19 is not only acute but also causes a post COVID-19 condition (PCC). In this study, we investigated trends in PCC. Methods: This was a single-center, retrospective observational study from February 15, 2021 to March 31, 2023 in Okayama in Japan. We summaries the weekly trends and epidemiological aspects of PCC and reported COVID-19 cases. Results: The weekly number of PCC-related visits by the date of COVID-19 onset showed a trend similar to that of COVID-19 cases. Weekly visits to CAC tended to increase several months after each pandemic wave. The incidence rates of PCC in the Omicron-dominant period were one-tenth of those during the Delta-dominant period. Conclusion: This study revealed that the number of PCC-related visits tended to increase a few onths after an increase in COVID-19 cases. The number of patients with PCC is expected to further increase in the near future owing to Omicron variants.