Table 2.

Potential mechanisms of milder COVID-19 in asthmatic children

Hypothetical factors	Plausible modes
Th2-driven inflammation	IL-4, IL-5 and IL-13 lead to lower ACE2 expression in respiratory cells
Eosinophils	Reduction of viral load with subsequent attenuation of COVID-19
Inhaled corticosteroids as the main treatment	Downregulation of ACE2 and TMPRSS2 gene expression. Additionally, IL-6 and IL-8 suppression

TMPRSS2 transmembrane protease serine 2

ACE2 angiotensin converting enzyme 2

Th2 T helper 2

IL interleukin