The risk of bronchiolitis hospitalisation following administration of a group B meningococcal vaccine in New Zealand.

AIM: During the Phase II clinical trials for a new group B meningococcal vaccine in New Zealand, six study participants (including five children who had been vaccinated with this vaccine) were hospitalised due to acute bronchiolitis. We examined more closely the potential association between bronchiolitis hospitalisation and this vaccine.

METHODS

We used descriptive comparisons, a cohort analysis, and a matched case-control study to examine the potential association of bronchiolitis hospitalisation with the vaccine using New Zealand Health Information Service hospital discharge data and vaccination data from the National Immunisation Register.

RESULTS

The distribution of hospitalised bronchiolitis cases throughout New Zealand immediately following the introduction of the vaccine was consistent with historical (pre-vaccine) patterns. Similarly, all point estimates for relative risk (cohort analysis) and odds ratio (case-control study) for assessing the potential association between bronchiolitis hospitalisation and the vaccine were less than 1.00.

CONCLUSIONS

We concluded that this vaccine is not associated with an increased risk of hospitalisation for bronchiolitis.