The Efficacy of Live Attenuated, Cold-Adapted, Trivalent, Intranasal Influenzavirus Vaccine in Children

Influenza A and B viruses are among the most common causes of respiratory tract illnesses that bring children to medical care, and influenza is a major cause of lower respiratory tract illness in young children. 1 The annual incidence of influenza infection in children may exceed 30 percent, 2 and children are believed to be important in the spread of influenza in the community. 3 Despite the availability of inactivated influenzavirus vaccine for children, the vaccine is used infrequently in this age group. 4 Live attenuated, cold-adapted, trivalent influenzavirus vaccine that is given intranasally may represent a convenient and effective approach to the prevention . . .