A decade of vaccinating allergic travellers: a clinical audit

Adverse reactions following vaccination are rare but may include potentially fatal anaphylaxis. This audit is a retrospective review of 38 patients with a history, or potential risk, of 'vaccine allergy' referred to an Infectious Diseases Unit for vaccination over a 10 year period. A total of 59 patient encounters were recorded, of which 89.8% were uneventful. Of the 6 adverse events, 3 patients had a local reaction, 1 patient developed urticaria and 1 patient had a vasovagal episode. Only 1 patient developed anaphylaxis secondary to vaccination, and she had no prior history of vaccine allergy. Of these patients 17 had a history suggesting the need for immunological investigation but only 7 had laboratory evidence of allergy. The differential diagnosis of anaphylaxis includes vasovagal reactions and non-specific mediator release and immunological work-up of such events can help avoid such patients being incorrectly labelled as allergic. The vast majority of immunisations are uncomplicated and patients with a history of allergic reactions to vaccination may be vaccinated safely in a controlled setting. Unduly conservative guidelines risk withholding vaccines providing protection against dangerous pathogens but which can be safely administered.