Nebulized live-attenuated influenza vaccine provides protection in ferrets at a reduced dose

► LAIV nasal vaccination in ferrets using a high efficiency nebulizer was investigated. ► LAIV was effectively delivered to the upper airways and was immunogenic after aerosol delivery. ► Despite the failure to isolate virus there was induction of protective levels of serum antibodies. ► Aerosol vaccination was protective against homologous challenge in ferrets. ► Aerosol vaccination decreased the length and amount of virus shed after heterotypic challenge.