Cytokines called Interleukin-13 (IL-13), which play a key role in protecting cells against SARS-CoV-2, help explain the mystery of why people with allergic asthma fare as compared to the general population despite having a chronic lung condition. Though the same cannot be said for individuals with other diseases, such as chronic obstructive pulmonary disease (COPD) or emphysema, who are at very high risk of severe COVID, a recent research conducted by scientists from the University of North Carolina at Chapel Hill, revealed that asthma patients are less susceptible to severe COVID. The findings of the study, published in the Proceedings of the National Academy of Sciences, indicated the importance of a well-known cytokine called interleukin-13 (IL-13) in protecting cells against coronavirus, which contributes to the lesser risk of COVID-19 in asthma patients. The researchers said that they used genetic analysis of human airway cell cultures infected with SARS-CoV-2 and electron microscopy (EM) later on to find severe cytopathogenesis – changes inside human cells due to viral infection.