Clinical efficacy of the RIT 4237 live attenuated XXXX rotavirus vaccine in @entity1 vaccinated before a rotavirus @entity3082 .

@entity1 @entity3082 @entity294 @entity18330 @entity291
In a randomized, double-blind, placebo-controlled trial, 331 @entity1 aged 6 to 12 months received orally, at an interval of 1 month, either two doses of live attenuated @entity291 rotavirus vaccine strain RIT 4237 or equivalent placebo. The vaccinations were carried out during September to November, a non-rotavirus season; only three cases of rotavirus @entity294 occurred in the study group before the vaccinations were completed. During the @entity3082 season from December to May, 31 @entity1 with clinically significant rotavirus @entity294 required therapy. Five of these were among the 168 vaccine recipients, and 26 among the 160 placebo recipients (P less than 0.001), giving a vaccine protection rate of 82%. The incidence of clinically significant @entity294 from all causes was reduced by 76% in the vaccinees. As determined by an enzyme immunoassay antibody test with homologous virus antigen, seroconversion after vaccination was obtained in 53% of the initially seronegative @entity1 . Clinical protection correlated well with seroconversion, but the vaccinees who failed to seroconvert also had less rotavirus @entity294 than the placebo recipients, suggesting that immunity may be mediated by factors other than serum EIA antibody. Seventeen of the 23 rotavirus isolates in the @entity3082 season that were typed were of serotype 1, two were of serotype 2, and four were of serotype 3. The protection rates against clinically significant @entity294 were 72%, 100%, and 100% for serotypes 1, 2, and 3, respectively. We conclude that @entity18330 associated with @entity1 rotaviruses can be significantly reduced by vaccination with the live attenuated RIT 4237 @entity291 rotavirus vaccine before the @entity3082 season.
