Because of their important role in the pathophysiology of severe RSV infection, IFNs represent an ideal group of candidate genes for determining RSV disease severity. We studied 14 polymorphisms within 7 genes involved in IFNs signalling. Our study populations consisted of 156 infants with severe RSV infection and 296 healthy control children. None of the genes showed association with severe RSV infection in children. Thus, despite the involvement of different IFNs in the pathophysiology of RSV infection, genetic variants in IFNG and related genes might not alter the risk for the development of severe RSV-associated diseases.