Prophylactic Paracetamol After Meningococcal B Vaccination Reduces Postvaccination Fever and Septic Screens in Hospitalized Preterm Infants.

Background: Following the introduction of the 4CMenB (Bexsero, GlaxoSmithKline, Rixensart, Belgium) vaccine against Meningococcal B into the UK vaccination schedule, Public Health England advised paracetamol to be given prophylactically with the vaccine. This was based on observations of increased postvaccination febrile reactions in term infants. Evidence in preterm infants was lacking. We aimed to evaluate whether (i) 4CmenB is associated with an increase in adverse events (AEs) in the 48 hours after vaccination in preterm infants and (ii) the impact of prophylactic paracetamol on AEs.

Methods: Retrospective case-note review of preterm infants, within a UK level 3 neonatal unit, receiving first or second 4CMenB vaccination, within 3 periods; (i) period 1 (pre-4CMenB): September 2014-September 2015; (ii) period 2 (4CMenB without prophylactic paracetamol): September 2015-March 2016 and (iii) period 3 (4CMenB with prophylactic paracetamol): June 2016-May 2018. Data were collected on a predefined list of postvaccination AEs within 48 hours of vaccination: (i) number (%) of infants with temperature >37.5°C; (ii) highest temperature (°C); (iii) number (%) of infants receiving evaluation for sepsis and (iv) number (%) of infants receiving intravenous antibiotics.

Results: Ninety-five vaccination episodes were included. Compared with the pre-4CMenB (period 1), more infants developed temperature >37.5°C, needed partial septic screens and had intravenous antibiotics when 4CMenB was introduced without paracetamol prophylaxis (period 2). Paracetamol prophylaxis (period 3) with 4CMenB resulted in fewer infants experiencing postvaccination fever and antibiotic administration comparable to period 1.

Conclusions: 4CMenB is associated with AEs in hospitalized preterm infants. Prophylactic paracetamol administration attenuates this.