IL4 and infection: A number of secreted factors have been demonstrated to be released following infection with RSV, including: IL-1α, IL-1β, IL-4, IL-5, IL-6, IL-8, IL-10, IL-12, IL-13, IL-15, IL-17A, IL-18, TNF-α, IFN-α, IFN-β and IFN-λ [7], [10], [34], [35], [36], [37], [38], [39], [40].