To evaluate other RSV-induced pathology by Bac-RSV/G immunization, we monitored weight loss in all immune-mice after RSV challenge. Following infection with live RSV, there was no significant weight loss in Bac-RSV/G-immune mice (Fig. 7B ) and disease score (data not shown). Taken together, these results suggest that intranasal Bac-RSV/G vaccination give rise to protective immunity in the absence of subsequent vaccine-enhanced disease.