Nephrotic syndrome in infants and toddlers before and after introduction of the meningococcal B vaccine programme in England: An ecological study.

A possible increased risk of nephrotic syndrome (NS) following a meningococal group B vaccination campaign was identified during active safety surveillance in a province in Quebec, Canada where 4 cases were reported from an exposed population of ~490,000, a higher rate than in provinces not using the vaccine. Meningococcal B vaccine has been given routinely at 2, 4 and 12 months of age in the United Kingdom since September 2015. To investigate the Canadian signal we used English hospital admissions data from 2005 to 2019 in 2-23 month old children to determine whether the rate of NS changed following the introduction of the vaccine. The analysis was stratified by age 2-5 months, 6-11 months, 12-17 months and 18-23 months. The results showed no evidence of an increased risk with incidence rate ratios between 0.81 (95% confidence interval 0.56-1.19) for age 6-11 months and 1.18 (0.84-1.66) for age 12-17 months.