COVID-19 Infection Raises Risk of Asthma and Other Respiratory Type-2 Inflammatory Diseases

Philip Curman, PhD

Courtesy of Nordiska Kliniken

A large-scale US cohort study has found that COVID-19 infection is associated with an increased short-term risk of developing respiratory type-2 inflammatory diseases (T2IDs), including asthma, allergic rhinitis, and chronic rhinosinusitis, while vaccination against the virus appears to reduce these risks.

Researchers analyzed electronic health record data from more than 118 million adults in the TriNetX database, comparing three propensity score–matched cohorts: individuals with COVID-19 infection (n=973 794), individuals with COVID-19 vaccination but no documented infection (n=691 270), and unexposed controls (n=4 388 409). Participants were followed for three months after their index event to assess new-onset asthma, allergic rhinitis, chronic rhinosinusitis, atopic dermatitis, and eosinophilic esophagitis.

Compared with controls, COVID-19 infection was associated with higher risks for asthma (hazard ratio [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). No significant risk increases were observed for atopic dermatitis or eosinophilic esophagitis.

In contrast, COVID-19 vaccination was linked to lower risks of asthma (HR, 0.678; 95% CI, 0.636–0.722) and chronic rhinosinusitis (HR, 0.799; 95% CI, 0.752–0.850) compared with controls. A smaller but statistically significant reduction in allergic rhinitis risk was also noted (HR, 0.927; 95% CI, 0.872–0.985). No effect on atopic dermatitis or eosinophilic esophagitis risk was detected.

Direct comparison between infected and vaccinated participants showed a more than twofold higher risk for asthma (HR, 2.463; 95% CI, 2.320–2.614) and chronic rhinosinusitis (HR, 2.227; 95% CI, 2.105–2.357) and a 1.4-fold higher risk for allergic rhinitis (HR, 1.402; 95% CI, 1.321–1.488) among those infected.

The authors noted that the elevated risks appeared limited to respiratory manifestations of type-2 inflammation, possibly reflecting higher viral loads in respiratory tissues. They suggested that vaccination may attenuate post-infectious immune responses that contribute to these outcomes.

"The findings emphasize type-2 inflammation as a possible driver of respiratory sequelae while showing that this response is primarily restricted to the respiratory tract," researchers concluded. "These results reinforce the critical role of vaccination in reducing morbidity and support ongoing public health efforts to promote immunization globally."

Source: Olbrich H, Preuß SL, Kridin K, et al. COVID-19 infection raises respiratory type-2 inflammatory disease risk, whereas vaccination is protective. J Allergy Clin Immunol. Published online August 12, 2025. doi:10.1016/j.jaci.2025.07.030