IFNA1 and infection: Moreover, the fact that NSVs containing 5′ triphosphates elicit strong cytokine responses despite the presence of IFN-antagonistic proteins indicates that the balance between induction and viral inhibition is disturbed at some point during infection, possibly by a surplus of non-functional genomes such as produced by defective interfering particles [36] or by infection of cells which are resistant to the action of viral IFN antagonists.