Post COVID-19 condition after SARS-CoV-2 infections during the omicron surge compared with the delta, alpha, and wild-type periods in Stockholm, Sweden.

Little is known about post COVID-19 condition (PCC) after infections with different SARS-CoV-2 variants. We investigated the risk of PCC diagnosis after primary omicron infections compared with preceding variants in population-based cohorts in Stockholm, Sweden. Compared to omicron (n=215,279, 0.2% receiving a PCC diagnosis), the adjusted hazard ratio (95% confidence interval) was 3.26 (2.80 to 3.80) for delta (n=52,182, 0.5% PCC diagnosis), 5.33 (4.73 to 5.99) for alpha (n=97,978, 1.0% PCC diagnosis), and 6.31 (5.64 to 7.06) for wild-type (n=107,920, 1.3% PCC diagnosis). These findings were consistent across all subgroup analyses except among the ICU-treated.