Among PRV recipients, there was a 23.1% (95% CI: 8.8,35.1) reduction in use of ORS during the study period (Table 5). There were no differences between groups in use of antibiotics, clinic visitation or hospital admissions. Based on the efficacy against all-cause gastroenteritis with severe dehydration at the home visits (34.4%) and severe RVGE in the clinic-based catchment design (83.4%) in the first year of life, we estimate that 41.2% of gastroenteritis with severe dehydration check details in the first year of life that occurred in the community was due to rotavirus. Among severe RVGE cases included in the analysis with complete molecular testing results, the majority 88.9% (16/18)

were found to be caused by rotaviruses with G and/or P genotypes included in PRV. Among PRV and placebo recipients, 5 (100%) and 9 (64%) strains belonged to genotype G1P[8], respectively; among placebo recipients GS-7340 mouse there was one rotavirus strain each of the following genotypes: G8P[6], G9P[6], G10P[8], G[untypeable]P[8], and G[untypeable]P[6]. Among 93 RVGE cases of all severity (not all were in evaluable children), 85 had complete molecular testing results; of these, 62 (73%) were caused by rotavirus strains with genotypes included in PRV (Fig. 2). The most common non-vaccine genotype was G8P[6], which accounted for 21% of evaluable rotavirus strains.

Among study participants, the most common bacterial pathogens for both PRV and placebo recipients were Campylobacter, Salmonella Group B (likely S. typhimurium), and Shigella ( Table 6). There were no significant differences in the prevalence or distribution of bacterial pathogens between groups. In rural western Kenya, PRV provided significant protection (83%) against severe RVGE through the first year of life, the period of highest

rotavirus incidence and mortality [3], [5], [13] and [20]. Despite having wide confidence intervals, the overall point estimate for efficacy seen in Kenya was similar to that described (76.9%) for the monovalent live attenuated human rotavirus vaccine observed in the first year of life in South Africa (76.9%), not a more developed African country, and Malawi (49.4%), a country with similar demographic and socioeconomic profile as western Kenya [6]. We found that PRV prevented approximately one-third of all-cause gastroenteritis with severe dehydration in the first year of life reported in the community. This finding was reinforced by observing a significant reduction of severe cases using a second severity score, the modified Clark Clinical Scoring System, which included more clinical variables than the IMCI definition, and, also a reduction in the use of ORS among PRV recipients. The efficacy from home visits was similar to that found for all-cause severe gastroenteritis in the first year of life in the community in a trial of the monovalent rotavirus vaccine in Malawi and South Africa (efficacy 30.2%) [6].