It has been widely described that excessive inflammation, and in particular IL-17-mediated inflammation, can result in detrimental immunopathology during Aspergillus infections in mice36–39, but this is primarily observed in situations where the immune system is largely functional such as cystic fibrosis, allergic bronchopulmoary aspergillosis, corticosteroid, and fully immunocompetent models. The gene discussed is IL17A; the disease is cystic fibrosis.