Background Live attenuated influenza vaccine (LAIV) is an intranasal vaccine recently incorporated into the United Kingdom immunization schedule. However, it contains egg protein and, in the absence of safety data, is contraindicated in patients with egg allergy. Furthermore, North American guidelines recommend against its use in asthmatic children. Objective We sought to assess the safety of LAIV in children with egg allergy. Methods We performed a prospective, multicenter, open-label, phase IV intervention study involving 11 secondary/tertiary centers in the United Kingdom. Children with egg allergy (defined as a convincing clinical reaction to egg within the past 12 months and/or >95% likelihood of clinical egg allergy as per published criteria) were recruited. LAIV was administered under medical supervision, with observation for 1 hour and telephone follow-up 72 hours later. Results Four hundred thirty-three doses were administered to 282 children with egg allergy (median, 4.9 years; range, 2-17 years); 115 (41%) had experienced prior anaphylaxis to egg. A physician's diagnosis of asthma/recurrent wheezing was noted in 67%, and 51% were receiving regular preventer therapy. There were no systemic allergic reactions (upper 95% CI for population, 1.3%). Eight children experienced mild self-limiting symptoms, which might have been due an IgE-mediated allergic reaction. Twenty-six (9.4%; 95% CI for population, 6.2% to 13.4%) children experienced lower respiratory tract symptoms within 72 hours, including 13 with parent-reported wheeze. None of these episodes required medical intervention beyond routine treatment. Conclusions In contrast to current recommendations, LAIV appears to be safe for use in children with egg allergy. Furthermore, the vaccine appears to be well tolerated in children with a diagnosis of asthma or recurrent wheeze.
Bibliographical noteFunding Information:
Disclosure of potential conflict of interest: P. J. Turner has received research support from the United Kingdom Department of Health , the UK Medical Research Council , and the National Institute for Health Research . M. Erlewyn-Lajeuness has received support for attendance at scientific meetings from Allergy Therapeutics, ALK-Abelló, MEDA Pharmaceuticals, and Thermo Fisher. The rest of the authors declare that they have no relevant conflicts of interest.
This report is independent research commissioned and funded by the Department of Health Policy Research Programme (National Vaccine Evaluation Consortium, 039/0031). The views expressed in this publication are those of the authors and not necessarily those of the Department of Health. The study received additional local support through the NIHR Clinical Research Networks, with additional funding for a Scottish site from Health Protection Scotland . P.J.T. and M.E.-L had financial support from the Department of Health for the submitted work. P.J.T. is a recipient of a Clinician Scientist award from the UK Medical Research Council (grant MR/K010468/1 ) and is supported by the National Institute for Health Research (NIHR) Imperial Biomedical Research Centre and the MRC–Asthma UK Centre in Allergic Mechanisms of Asthma.
© 2015 The Authors.
- Egg allergy
- live attenuated influenza vaccine
- recurrent wheezing