Nephrotic syndrome following four-component meningococcal B vaccination: Epidemiologic investigation of a surveillance signal.

BACKGROUND: In May 2014, a mass vaccination campaign with four-component meningococcal serogroup B (4CMenB) vaccine was launched in a localized region of Quebec, Canada experiencing high invasive meningococcal B disease endemicity. Active post-marketing surveillance identified several cases of nephrotic syndrome (NS) among ∼49,000 vaccinated individuals aged 2 months to 20 years. We report the epidemiologic investigation of this potential vaccine safety signal. METHODS: Active vaccine safety surveillance was conducted electronically, with participants completing an online questionnaire prompted at 7 days after each dose and 6 months following the last dose. Additional NS cases were sought from provincial hospitalization and emergency room databases. RESULTS: In the year following the first dose of 4CMenB vaccination, four confirmed NS cases (three hospitalized) were identified among vaccinated children 2-5-years-old with onset several months post-vaccination. None had renal biopsy but given their age, and positive response to steroids, idiopathic NS was presumptively diagnosed. Among vaccinated children 1-9-years-old, the NS incidence in the year post-vaccination was 17.7 per 100,000 (1 per 5650 vaccinees) with an NS hospitalization rate (i.e. excluding the outpatient case) that was 3.6-fold higher (95%CI = 0.7-11.8; p = 0.12) than the rest of the province for the same period, and 8.3-fold greater (95%CI = 1.1-62.0; p = 0.039) than during the eight years preceding the immunization campaign in the affected region. CONCLUSION: Active safety surveillance identified an unexpected increase in NS incidence following 4CMenB vaccination. Further epidemiological investigation identified four vaccinated cases in total over a 12 month period of follow up. The greater risk in vaccinees had wide confidence intervals with he lower limit including or just above the nul value, an observation with no or marginal statistical significance. The temporal association with vaccination may be explained by other causes and/or chance clustering of a rare event unrelated to vaccination. To confirm or refute a potential link to vaccination, surveillance in other jurisdictions administering 4CMenB to children 1-9-years-old is needed.

Parents' and adolescents' willingness to be vaccinated against serogroup B meningococcal disease during a mass vaccination in Saguenay-Lac-St-Jean (Quebec).

A mass vaccination campaign with the 4CMenB vaccine (Bexsero®; Novartis Pharmaceutical Canada Inc) was launched in a serogroup B endemic area in Quebec. A telephone survey was conducted to assess parental and adolescent opinions about the acceptability of the vaccine. Intent to receive the vaccine or vaccine receipt was reported by the majority of parents (93%) and adolescents (75%). Meningitis was perceived as being a dangerous disease by the majority of parents and adolescents. The majority of respondents also considered the 4CMenB vaccine to be safe and effective. The main reason for positive vaccination intention or behaviour was self-protection, while a negative attitude toward vaccination in general was the main reason mentioned by parents who did not intend to have their child vaccinated. Adolescents mainly reported lack of interest, time or information, and low perceived susceptibility and disease severity as the main reasons for not intending to be vaccinated or not being vaccinated.

Une campagne de vaccination de masse avec le vaccin 4CMenB (Bexsero®; Novartis Pharma Canada Inc.) a été lancée dans une région du Québec endémique au sérogroupe B. Un sondage téléphonique afin d'évaluer l'acceptabilité du vaccin par les parents et les adolescents a été réalisé. La majorité des parents (93 %) et des adolescents (75 %) ont déclaré avoir l'intention de se faire vacciner / de faire vacciner leur enfant ou l'avoir déjà fait. La majorité des parents et des adolescents percevaient la méningite comme dangereuse et considéraient le vaccin 4CMenB comme sécuritaire et efficace. La protection de l'enfant était la principale raison d'accepter le vaccin chez les parents, tandis qu'une attitude négative envers la vaccination en général était la principale raison que donnaient les parents qui n'avaient pas l'intention de faire vacciner leur enfant. Les adolescents déclaraient surtout un manque d'intérêt, de temps ou d'information, la perception d'être peu susceptibles à la maladie et la perception que la maladie n'était pas très grave comme principales raisons de ne pas s'être fait vacciner ou de ne pas avoir l'intention de le faire.