Our finding of elevated nasal and bronchial levels of IFN-γ and IFN-λ (together with the IFN-inducible proteins CXCL10/IP10, CXCL11/ITAC and IL-15) is in agreement with elevated IFN-γ and IFN-λ responses to virus infection being found in vivo in children with asthma (Lewis et al., 2012, Miller et al., 2012). Here, IFNG is linked to asthma.