Josephine van Dongen

5 Safety and Tolerability of Human Rotavirus Vaccination 123 2) Tolerability The group of high-risk par ticipating premature infants ≥ 27 weeks of GA consisted of 1206 infants. Data on at least one vaccine administration and AE were available for 1041 (86.3%) infants, including 471 in the NIP only and 570 in the NIP+HRV group ( figure 2 ). Patient characteristics of NIP versus NIP +HRV vaccinated infants were largely comparable ( table 1 ). Age at first vaccination was slightly younger among HRV vaccinated infants (59 days versus 61 days of postnatal age, p=0.0). In the seven days following 1350 vaccinations any AE was repor ted out of 3031 repor ted vaccine administrations (44.5%). The total number of repor ted AE was 2057, resulting in an incidence rate of 0.68 (95%CI 0.65;0.71) per vaccine administration. A total of 134 vaccine administrations were followed by an AE related healthcare contact (4.4%). Figure 2 . Flowchar t of high-risk premature infants and cohor t study-par ticipants with gestational age between 27 and 37 weeks. $ Reasons for not approaching eligible infants: 446 versus 484 discharged or referred, 154 versus 124 language barrier, 147 versus 80 unstable social environment, 38 versus 41 poor prognosis, 96 versus 130 other unspecified reason, 14 missing and 1626 eligible during follow-up, when recruitment for cohor t study was ended. Abbreviations: HRV = human rotavirus vaccine, NIP = national immunization program, AE = solicited adverse event.