BACKGROUND: Rotavirus (RV) vaccination in the US has reduced RV illness among infants, but concerns about safety persist after the 1999 withdrawal of a RV vaccine due to increased intussusception risk.
OBJECTIVES: To determine the short-term risk of adverse events associated with RV vaccination in infants overall and by vaccine formulations (3-dose pentavalent RV5; 2-dose monovalent RV1).
METHODS: We identified infants in US commercial insurance claims (2006–2014) who received diphtheria-tetanus-pertussis (DTaP) vaccines; we determined if a RV dose was given on the same day, as RV and DTaP follow similar recommended dosing schedules for doses 1 and 2 (first dose at 2 months, second dose at 4 months). DTaP coverage is almost universal; excluding infants without DTaP lessened potential biases caused by the differences between vaccine receivers and non-receivers. We followed infants for up to 30 days after each vaccine dose and recorded diagnoses of intussusception, other gastrointestinal events, neurologic events, otitis media, emergency department visits, and hospitalizations. We compared infants receiving DTaP + RV to those receiving DTaP alone. We also compared infants receiving DTaP + RV5 to those receiving DTaP + RV1. Analyses were performed separately for the first and second DTaP doses. We estimated adjusted hazard ratios (HR) and 95% confidence intervals (CI) with multivariable Cox proportional hazards models.
RESULTS: We identified 1,031,431 and 821,833 infants with first and second doses of DTaP, respectively; 80.8% of DTaP doses had a concurrent RV vaccine, 92.6% of which were RV5. Absolute risks of most outcomes were very low. Compared to DTaP alone, there was no increased risk of intussusception or any other outcome except otitis media: dose 1, HR = 1.07 (95% CI: 1.03–1.11); dose 2, HR = 1.16 (95% CI: 1.12–1.19). When comparing RV5 to RV1, RV5 had a lower risk of otitis media; dose 1, HR = 0.92, (95% CI: 0.86–0.97); dose 2, HR = 0.93 (95% CI: 0.89–0.98). There were no differences in risks of the other outcomes.
CONCLUSIONS: RV vaccination was not associated with adverse events, except for a small increased risk of otitis media, particularly in those receiving RV1.
