Safety of Inactivated Influenza Vaccine in Patients with Egg Allergy in Kurdistan Province, Iran.

Most influenza vaccines are grown in embryonated eggs and residual egg proteins can cause allergic reactions in patients with egg allergy. The aim of the present study was to determine the safety of inactivated influenza vaccine in patients with egg allergy in Kurdistan Province, Iran.This case-control study was done on 876 patients referred to Kurdistan Asthma and Allergy Clinic, Sanandaj, Iran; 635 patients with egg allergy (cases) and 241 patients without egg allergy (controls) from 2012 to 2016. All of the patients were injected seasonal influenza vaccine. Side effects including anaphylactic shock, local reaction, vomiting, coughing, sneezing, wheezing, low blood pressure, redness and itching in the eyes, abdominal pain, dyspnea, oral/facial angioedema, swollen and itching of throat were checked by an allergist within 30 min after vaccination, and followed up to 24 h. Demographic and vaccination data were entered into the SPSS software and analyzed.

Out of 876 patients, 460 (52.5%) were male. Patients' ages ranged from 6 months to 80 yr (mean 13.38 ± 15.22 SD). Overall, 63 patients with egg allergy had local reactions to vaccine. Difference of local reactions between case and control groups was statistically significant (P=0.001). No anaphylactic reactions were seen after vaccination.

Although the risk of anaphylactic reactions to influenza vaccine in patients with egg allergy was rare, the vaccine should be administered by an allergist with precaution. The results of present study can be a confirmation of the existing evidences to prevent acute complications to influenza vaccine.