David J. Amrol, MD reviewing Turner PJ et al. BMJ 2015 Dec 8. Greenhawt M. BMJ 2015 Dec 9.
The majority of influenza vaccines available are grown in hens’ eggs and may contain trace amounts of egg protein. After studies showed its safety in egg-allergic patients, in 2012 the CDC recommended that patients with mild egg allergy (only hives) can safely receive the injectable
inactivated influenza vaccine, and that those with severe egg allergy should receive it from a clinician experienced in treating anaphylaxis. The CDC still does not recommend the intranasal live attenuated influenza vaccine (LAIV) for egg-allergic patients.
To examine the safety of LAIV in children with egg allergy, investigators recruited 779 children and adolescents (age range, 2–18 years) from U.K. allergy centers to participate in an open-label study. Thirty-five percent of patients had experienced previous anaphylaxis due to egg exposure, and 57% had asthma or recurrent wheezing (but had not wheezed in the 3 days prior to vaccination).
No systemic allergic reactions occurred, and only 1% of patients had mild local symptoms. Asthma control did not worsen in the 4 weeks after vaccination.
Based on this and other studies, there is minimal, if any, risk for severe allergic reactions to either the injectable or intranasal preparations of influenza vaccine that are derived in eggs. The risk for influenza complications is far greater than any theoretical risk for anaphylaxis. In addition, as long as asthmatic patients have not wheezed in the previous 3 days, LAIV carries minimal risk for asthma exacerbations. Egg allergy and asthma should no longer be barriers to universal childhood influenza vaccination.
Turner PJ et al. Safety of live attenuated influenza vaccine in young people with egg allergy: Multicentre prospective cohort study. BMJ 2015
Dec 8; 351:h6291. (http://dx.doi.org/10.1136/bmj.h6291) Abstract/FREE Full Text
Greenhawt M.Live attenuated influenza vaccine for children with egg allergy. BMJ 2015 Dec 9; 351:h6656. (http://dx.doi.org/10.1136/bmj.h6656) FREE Full Text