title: Safety of live attenuated influenza vaccine in young people with egg allergy: multicentre prospective cohort study.
abstract: OBJECTIVE
  How safe is live attenuated influenza vaccine (LAIV), which contains egg protein, in young people with egg allergy?
  
  
  METHODS
  In this open label, phase IV intervention study, 779 young people (2-18 years) with egg allergy were recruited from 30 UK allergy centres and immunised with LAIV. The cohort included 270 (34.7%) young people with previous anaphylaxis to egg, of whom 157 (20.1%) had experienced respiratory and/or cardiovascular symptoms. 445 (57.1%) had doctor diagnosed asthma or recurrent wheeze. Participants were observed for at least 30 minutes after vaccination and followed-up by telephone 72 hours later. Participants with a history of recurrent wheeze or asthma underwent further follow-up four weeks later. The main outcome measure was incidence of an adverse event within two hours of vaccination in young people with egg allergy.
  
  
  CONCLUSIONS
  No systemic allergic reactions occurred (upper 95% confidence interval for population 0.47% and in participants with anaphylaxis to egg 1.36%). Nine participants (1.2%, 95% CI 0.5% to 2.2%) experienced mild symptoms, potentially consistent with a local, IgE mediated allergic reaction. Delayed events potentially related to the vaccine were reported in 221 participants. 62 participants (8.1%, 95% CI for population 6.3% to 10.3%) experienced lower respiratory tract symptoms within 72 hours, including 29 with parent reported wheeze. No participants were admitted to hospital. No increase in lower respiratory tract symptoms occurred in the four weeks after vaccination (assessed with asthma control test). The study cohort may represent young people with more severe allergy requiring specialist input, since they were recruited from secondary and tertiary allergy centres.
  
  
  CONCLUSIONS
  LAIV is associated with a low risk of systemic allergic reactions in young people with egg allergy. The vaccine seems to be well tolerated in those with well controlled asthma or recurrent wheeze.
  
  
  BACKGROUND
  This report is independent research commissioned and funded by a Department of Health policy research programme grant to the National Vaccine Evaluation Consortium. Additional funding was provided by the NIHR Clinical Research Networks, Health Protection Scotland (Edinburgh site), and Health & Social Care Services in Northern Ireland (Belfast site). PJT and MEL had support from the Department of Health for the submitted work; PJT has received research grants from the Medical Research Council and NIHR. No additional data available.Study registration ClinicalTrials.gov (NCT02111512) and the EU Clinical Trials Register EudraCT (2014-001537-92).
authors.affiliation: Section of Paediatrics, Imperial College London, London W2 1PG, UK Immunisation Hepatitis and Blood Safety Department, Public Health England, London, UK p.turner@imperial.ac.uk.
authors.forename: Paul J
authors.initials: PJ
authors.lastname: Turner
authors.affiliation: Immunisation Hepatitis and Blood Safety Department, Public Health England, London, UK.
authors.forename: Jo
authors.initials: J
authors.lastname: Southern
authors.affiliation: Immunisation Hepatitis and Blood Safety Department, Public Health England, London, UK.
authors.forename: Nick J
authors.initials: NJ
authors.lastname: Andrews
authors.affiliation: Immunisation Hepatitis and Blood Safety Department, Public Health England, London, UK.
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Miller
authors.affiliation: Paediatric Allergy and Immunology, Southampton University Hospital, Southampton, UK.
authors.forename: Michel
authors.initials: M
authors.lastname: Erlewyn-Lajeunesse
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D004305:Dose-Response Relationship, Drug; D021181:Egg Hypersensitivity / Q000150:complications*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D009980:Influenza A virus / Q000276:immunology*; D007252:Influenza Vaccines / Q000008:administration & dosage*; D007251:Influenza, Human / Q000150:complications / Q000517:prevention & control*; D008297:Male; D011446:Prospective Studies; D016896:Treatment Outcome; D006113:United Kingdom; D014611:Vaccination / Q000379:methods*; D014613:Vaccines, Attenuated / Q000008:administration & dosage
chemical_list: D007252:Influenza Vaccines; D014613:Vaccines, Attenuated