In a Swedish cohort, the risk of long COVID was much lower for vaccinated than unvaccinated participants in the year after infection, even when restricting the analyses to subgroups based on variant, age, sex, and previous infection status, estimates a study published last week in the Journal of Infectious Diseases.

Karolinska Institutet researchers in Stockholm analyzed data from five registries to compare rates of persistent COVID-19 symptoms, or post-COVID condition [PCC], in adults infected from January 2021 to February 2022 by vaccination status in the 14 days before infection. Follow-up was 365 to 660 days.