Influenza and respiratory syncytial virus are the two most important c
auses of viral lower respiratory tract disease. The innate immune resp
onse to these viruses, determined by multiple cell types, creates a cy
tokine milieu that affects the adaptive immune response and disease ma
nifestations. This review addresses the function of cytokines released
from cells resident in the respiratory tract after infection with inf
luenza and respiratory syncytial virus, and how differences in early c
ytokine release may impact disease pathogenesis and host response.