Sugiyama, A., Takafuta, T., Abe, K., Yoshinaga, Y., Ko, K., Sato, T., Akita, T., Kuwabara, M., Fukuma, S., Tanaka, J. (2026). Differences in the long-term course of post-COVID-19 symptoms in adults and children across epidemic periods: A retrospective cohort study in Japan, 2020–2024. PLoS ONE. https://doi.org/10.1371/journal.pone.0348954