H1N1 Vaccination: Recommendations for persons with chicken egg protein allergy

The European Centre for Allergy Research Foundation – ECARF recommends caution with regard to the vaccine against the H1N1 virus (also known as “swine flu”) for people with chicken egg protein allergies. Egg protein allergy predominantly affects children and young adults up to the age of 30.

As a result of the production process, influenza vaccines can contain measurable amounts of egg proteins. Vaccines free of egg protein are currently (as of 24 November 2009) available only in very few countries in Europe, for example in Austria. The H1N1 virus vaccine most commonly available in Germany, Pandemrix®, is produced from embryonic chicken egg cells. In the past, strong allergic reactions have been observed in individual cases after administration of the vaccine. The 1-2% of children affected by egg protein allergies and adults with existing or newly appearing egg protein allergies are at risk of experiencing an allergic reaction associated with the vaccine. The acuteness of the reaction depends on the severity of the egg protein allergy.

Comprehensive evidence has also been gathered regarding the use of vaccines produced using chicken egg cultures. This evidence shows that vaccination with these substances is possible in persons with a known egg protein allergy.

The European Centre for Allergy Research Foundation – ECARF makes the following recommendations with regard to the H1N1 vaccine for persons with egg protein allergy, in the case that no vaccine free of egg protein is available:

Low-level egg protein allergy

Persons with a low-level egg protein allergy who can eat cooked egg in small amounts or who experience only local symptoms upon consumption of a small amount of cooked egg (e.g. one teaspoon of scrambled egg) or raw egg can receive the vaccination from their general practitioner in keeping with the usual medical precautions, but should be sure to inform their physician of the allergy beforehand.

Severe egg protein allergy

Allergy sufferers with a severe egg protein allergy, who show positive results in a skin and/or blood test and who have experienced symptoms after consumption of a small amount of chicken egg (e.g. one teaspoon of scrambled egg), or who have a record of severe physical reactions (e.g. shortness of breath or skin rash) in their medical history, should be referred to the allergy centre of a clinic or a similar medical facility for administration of the H1N1 vaccine, so that the appropriate course of action can be determined according to all available information.

Hard-to-control asthma


Allergy sufferers with asthma that is difficult to control should be referred to the allergy centre of a clinic or a similar medical facility for the H1N1 vaccination, regardless of the severity of the egg protein allergy.

Vaccination procedure

In the case that a severe egg protein allergy is suspected, a skin test should be performed before the vaccine is administered. If the skin test is negative, it is recommended that the vaccine dose be administered in proportions, first one tenth and then nine tenths, with a waiting period of 30 minutes and in the presence of emergency medical personnel. If the vaccine produces a positive skin test result, a careful assessment of the risks and benefits must be carried out. In the case that the vaccination is deemed necessary, the dosage can be administered in incrementally increasing amounts. This option should be carried out only by allergy specialists with experience in the treatment of severe allergic reactions.

Summary

The risk of an allergic reaction to the H1N1 virus vaccine must be tested in persons with an egg protein allergy. Vaccines free of chicken egg protein are currently available only in very few European countries. For most patients with a low-level egg protein allergy, vaccination is possible under appropriate medical supervision. In the case of a pre-existing severe egg protein allergy, the vaccination must be administered under medical supervision in a hospital specialising in allergy treatment (allergy centre) and/or in a similarly specialised medical facility.

Press contact:

Matthias Colli
European Centre for Allergy Research Foundation – ECARF

Clinic for Dermatology, Venerology, and Allergology
Charité – Universitätsmedizin Berlin
Charitéplatz 1
D-10117 Berlin

Tel. +49-(0)30-450 518 050
matthias.colli(at)charite.de

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