COVID-19 infection raises respiratory type 2 inflammatory disease risk, whereas vaccination is protective

Background: Coronavirus disease 2019 (COVID-19) infection and vaccination have unclear impacts on type 2 inflammatory diseases. Although viral infections can drive immune dysregulation, the extent to which COVID-19 infection and vaccination affect type 2 inflammatory diseases in various organ systems remains underexplored. Objective: We sought to assess the risk of new-onset type 2 inflammatory diseases after COVID-19 infection and vaccination. Methods: We conducted a large-scale retrospective matched cohort study using a US electronic health records database of more than 118 million patients. Three cohorts were defined: individuals with COVID-19 infection (n = 973,794), individuals with COVID-19 vaccination (n = 691,270), and unexposed controls (n = 4,388,409). Propensity score matching balanced demographic and clinical covariates. We calculated hazard ratios (HRs) for incident asthma, allergic rhinitis, chronic rhinosinusitis, atopic dermatitis, and eosinophilic esophagitis over 3-month follow-up. Results: COVID-19 infection significantly increased the risks of asthma (HR 1.656, 95% CI 1.590-1.725), allergic rhinitis (HR 1.272, 95% CI 1.214-1.333), and chronic rhinosinusitis (HR 1.744, 95% CI 1.671-1.821). Risks for atopic dermatitis or eosinophilic esophagitis remained unchanged. In contrast, vaccination lowered the risks of asthma (HR 0.678, 95% CI 0.636-0.722) and chronic rhinosinusitis (HR 0.799, 95% CI 0.752-0.850). Direct comparison showed a 2- to 3-fold greater risk of respiratory type 2 inflammatory diseases with infection than with vaccination. Conclusions: COVID-19 infection is associated with a heightened risk of respiratory type 2 inflammatory diseases, whereas vaccination appears protective.