An efficacy trial of the rhesus rotavirus vaccine in Maryland. The Clinical Study Group
M. B. Rennels, G. A. Losonsky, A. E. Young, C. L. Shindledecker, A. Z. Kapikian and M. M. Levine
Center for Vaccine Development, University of Maryland School of Medicine, Baltimore.
A double-blind, placebo-controlled trial of oral rhesus rotavirus vaccine
at a dose of 10(4) plaque-forming units was performed in 114 young infants
in Maryland. Significantly more vaccinees than controls had fever and
vomiting during the week after vaccination, but these reactions were mild.
Of the vaccinees, 83% had a fourfold or greater rise in neutralizing
antibody to rhesus rotavirus vaccine and 69% shed vaccine virus. Seventeen
percent of the vaccinees and 24% of controls had rotavirus-positive
diarrhea during the 2 years of surveillance. Vaccine efficacy was therefore
29% (95% confidence limits, -31% to +66%). Stools from 12 of 13 episodes
containing sufficient antigen to type were serotype 1. We conclude that
rhesus rotavirus vaccine was infective, immunogenic, and probably
acceptably attenuated but that this serotype 3 vaccine provided little
heterotypic protection during serotype 1 outbreaks in the community.
