In the version of this News and Views originally published, the author made an incorrect reference to ‘mice deficient in Mx1’. This has now been corrected so that the text instead refers to ‘mice congenic for Mx1’. The full corrected sentence reads as “Pretreatment of mice congenic for Mx1, an ISG that is critical for protection of animals from influenza, with intranasal neomycin significantly improved survival; however, about 50% of the mice died.”