Objective 6–12-week-old healthy infants were randomly assigned to receive three oral doses of RotaTeq or placebo in the Rotavirus Efficacy and Safety Trial (REST). To determine if RotaTeq remains efficacious beyond 2 years after vaccination, approximately 21 000 REST infants in the Finnish safety cohort were followed for healthcare encounters, defined as rotavirus gastroenteritis (RVGE)-associated hospitalisations and/or emergency department visits, in the Finnish Extension Study (FES) for up to 3.1 years.

Methods The infants were contacted every 12 weeks to determine whether they had any RVGE-related healthcare encounters. RVGE was defined as forceful vomiting and/or three or more watery or looser-than-normal stools within a 24-h period and detection of rotavirus antigen by ELISA, plaque assay and PCR assays (P and G types). Infants with RVGE, who received three vaccine doses, were included in the analysis; follow-up started 14 days after dose 3.

Results The maximum follow-up time in FES was 3.1 years (1126 days). Overall, pentavalent rotavirus vaccine reduced the rate of RVGE-associated healthcare encounters, regardless of rotavirus serotype, by 94% (95% CI 91.3 to 95.9), demonstrating an overall reduction of healthcare-resource utilisation similar to that of REST (95% CI 91.5 to 96.5). See table for further details.

Conclusion RotaTeq significantly reduced RVGE-associated hospitalisations and emergency department visits for up to 3.1 years of follow-up. The results of FES are consistent with the results of REST and confirm that the efficacy of RotaTeq remains consistent beyond 2 years and up to 3.1 years.