IL6 and bronchiolitis: However, in some instances they can cause severe and potentially fatal conditions, such as aseptic meningitis, encephalitis, acute asthma exacerbations, bronchiolitis, viral pneumonia, myocarditis, acute flaccid paralysis, and hand-foot-and-mouth disease.2, , -5 The severity of respiratory symptoms in EV-HRV infection depends on the production of numerous pro-inflammatory cytokines and chemokines such as interleukin (IL)-1, IL-6, and IL-8.1 These pro-inflammatory molecules causes airway inflammation.