Viral infections causing asthma exacerbations in the age of biologics and the COVID-19 pandemic.

PURPOSE OF REVIEW:Asthma exacerbations are associated with substantial symptom burden and healthcare costs. Viral infections are the most common identified cause of asthma exacerbations. The epidemiology of viral respiratory infections has undergone a significant evolution during the COVID-19 pandemic. The relationship between viruses and asthmatic hosts has long been recognized but it is still incompletely understood. The use of newly approved asthma biologics has helped us understand this interaction better. RECENT FINDINGS:We review recent updates on the interaction between asthma and respiratory viruses, and we address how biologics and immunotherapies could affect this relationship by altering the respiratory mucosa cytokine milieu. By exploring the evolving epidemiological landscape of viral infections during the different phases of the COVID-19 pandemic, we emphasize the early post-pandemic stage, where a resurgence of pre-pandemic viruses with atypical seasonality patterns occurred. Finally, we discuss the newly developed RSV and SARS-CoV-2 vaccines and how they reduce respiratory infections. SUMMARY:Characterizing how respiratory viruses interact with asthmatic hosts will allow us to identify tailored therapies to reduce the burden of asthma exacerbations. New vaccination strategies are likely to shape the future viral asthma exacerbation landscape.