Rotavirus vaccination and short-term risk of adverse events in US infants.

BACKGROUND: The aim of this study was to evaluate the short-term risk of adverse events associated with rotavirus vaccine (RV) in infants, overall and by vaccine formulation (three-dose pentavalent, RV5; two-dose monovalent, RV1).

METHODS: We identified US newborns with commercial insurance during 2006-2014 receiving a diphtheria-tetanus-pertussis vaccine (DTaP) dose and assessed if RV was administered concurrently. We followed infants for 30 days after each dose for diagnoses of intussusception, other gastrointestinal events, seizures, Kawasaki disease, thrombocytopenia, otitis media, all-cause emergency department visits, and all-cause hospitalisations. We estimated adjusted hazard ratios (HR) and 95% confidence intervals (CI) with multivariable Cox proportional hazards models comparing: (a) those receiving DTaP+RV vs those receiving DTaP alone; and (b) RV5 vs RV1. Analyses were performed separately within DTaP doses and then meta-analysed across doses.

RESULTS: We identified 1 031 431 first DTaP doses, 821 833 second doses, and 615 293 third doses; 79.2% had a concurrent RV, 94.1% of which were RV5. Absolute risks of serious outcomes were very low. Compared to infants who received DTaP alone, infants who received RV+DTaP did not experience consistently increased risk of intussusception (hazard ratio [HR] 1.13, 95% confidence interval [CI] 0.68, 1.88) or any other outcome except for otitis media after dose 2: HR 1.11, 95% CI 1.08, 1.15. This increased otitis media risk was not as pronounced in RV5 when comparing RV5 to RV1; HR 0.92, 95% CI 0.89, 0.95.

CONCLUSIONS: These data were not consistent with an increased risk of intussusception or other adverse events following vaccination with RV, except potentially for a small increased risk of otitis media, particularly in RV1.