Post-coronavirus era: Should we expect a surge in allergic diseases and asthma?

Some infectious agents by priming the immune system promote protection against allergy and asthma. During infections, Th1 immune responses are dominant, while in allergic conditions, Th2 responses are more pronounced. Th1 immune response protects the body against infections, and Th2 response leads to allergy and asthma. For maintaining health, the balance between Th1 and Th2 responses is necessary. The COVID-19 infection augments Th1 and also eosinophilic responses. On the other hand, the main protocols to control the COVID-19 pandemic require adherence to health standards, maintaining personal hygiene, frequent disinfecting of hands, using face masks, etc. In the post-COVID-19 era, this sterile condition may relinquish, and the Th1/Th2 immune imbalance may lead to an increase in the incidence of allergy and asthma. Therefore, focus on the COVID-19 infection should not deter us from foreseeing a surge in asthma and other post-coronavirus problems.