Statistical analysis of a rhesus rotavirus vaccine trial to assess protective effect against diarrhea in Venezuelan children of 2-4 months of age

A statistical analysis of a rhesus rotavirus vaccine (RRV) trial to assess protective effect against rotavirus diarrhea was performed in venezuelan children. A total of 302 children, aged 1 to 10 months, were studied. Factors such as vaccine antigenicity, vaccination age, severity of illness, rotavirus shedding and vaccine efficacy were evaluated in order to optimize vaccine administration. An overall efficacy of 64% was found, but in the group of infants 2-4 months of age the efficacy level was the highest (92,8%). These results were supported by the higher rates of shedding an seroresponse observed in that group of infants. It was also observed that the vaccine reduces severity of diarrheal episodes