Each year, rotavirus gastroenteritis is responsible for about 37% of deaths from diarrhea among children younger than 5 years of age worldwide, with a disproportionate effect in sub-Saharan Africa.
Dr Sheila Isanaka and colleagues conducted a randomized, placebo-controlled trial in Niger to evaluate the efficacy of a live, oral bovine rotavirus pentavalent vaccine to prevent severe rotavirus gastroenteritis.
Healthy infants received 3 doses of the vaccine or placebo at 6, 10, and 14 weeks of age.
The research team evaluated episodes of gastroenteritis through active and passive surveillance, and graded these on the basis of the score on the Vesikari scale.
|Vaccine efficacy was 69%|
|New England Journal of Medicine|
The team's primary end point was the efficacy of 3 doses of vaccine as compared with placebo against a first episode of laboratory-confirmed severe rotavirus gastroenteritis beginning 28 days after dose 3.
Among the 3508 infants who were included in the per-protocol efficacy analysis, there were 31 cases of severe rotavirus gastroenteritis in the vaccine group, and 87 cases in the placebo group, for a vaccine efficacy of 67%.
The team observed similar efficacy in the intention-to-treat analyses, which showed a vaccine efficacy of 69%.
The researchers found no significant between-group difference in the risk of adverse events, which were reported in 69% of the infants in the vaccine group, and in 67% of those in the placebo group.
There was also no difference in the risk of serious adverse events.
The research team reported 27 deaths in the vaccine group, and 22 in the placebo group.
None of the infants had confirmed intussusception.
Dr Isanaka's team concludes, "Three doses of an oral rotavirus vaccine, had an efficacy of 67% against severe rotavirus gastroenteritis among infants in Niger."