Flu Vaccine and Egg Allergies

Flu Shots Contain Egg Protein Which May Lead to Allergic Reaction

Nov 14, 2009

While the flu vaccine is getting widespread support, it can be dangerous for a select population. Those with an allergy to egg may not be able to get the suggested shot.

During this flu season, it has been widely recommended that people get a seasonal flu shot, as well as the swine flu (also known as H1N1 flu) vaccine. Vaccination has been called the best defense we have to prepare for the flu. The expectation is that the swine flu vaccine will have the same safety record as the seasonal flu vaccine, which has been offered since the 1940s to millions of people each year.

History of Influenza Vaccine

It was the discovery of viral growth in embryonated hen egg in 1931 that led to the development of flu vaccine. The U.S. military was able to mass produce the vaccine and its use became widespread during World War II. Unfortunately, these egg-based vaccines may exclude people with an egg allergy from getting flu shots.

Each year, the seasonal flu vaccine and this year in the H1N1 vaccine, the serum contains a varying amount of egg. Every year is different, allowing someone with an egg allergy to successfully get the vaccine one year, only to have a serious reaction the next when the serum contains more egg protein. For people who may have an anaphylactic reaction to egg protein, the shot can cause a serious health risk, possibly even death. Generally, the CDC (Centers for Disease Control) recommends egg allergic individuals avoid both the seasonal and swine flu vaccines. However, some doctors will administer the shot if they believe the benefit outweighs the risk. Through a careful procedure that starts with a skin prick test to determine the level of sensitivity, doctors can administer small amounts of the vaccine over a period of time. This must be done in a closely monitored environment with a plan in place to deal with a possible allergic reaction.

Flu Vaccine Without Egg Protein

Newer methods for flu vaccine are on the horizon. Advances in molecular technology have allowed the creation of a flu vaccine that would be safe for those with an egg allergy. FluGen, Inc.® recently announced a cell-based production of flu vaccine that doesn't use egg in any part of the process. The company hopes to ramp up production and have vaccine ready "in the very near future." This cell-based process would save weeks in manufacture time and is less likely to become contaminated.

Another pharmaceutical company, Novartis®, also claims to be close to being able to offer a cell-based vaccine. They are hoping for U.S. shipment of cell-based swine flu vaccine in December 2009 or January 2010.

In the meantime, the difficult decision of whether a person with an egg allergy should receive the vaccine should be discussed with an allergist. It is possible for some egg allergic individuals to get the vaccine. For additional information about egg allergy and flu vaccination, check out a thorough list of recommendations from the Canadian Society of Allergy and Clinical Immunology. For those unable to tolerate the vaccine, the recommended practices of frequent hand washing and avoiding those who are sick, are the best defense against catching either the seasonal flu or the H1N1 strain of influenza.

The copyright of the article Flu Vaccine and Egg Allergies in Food Allergies is owned by Joanne LaSpina. Permission to republish Flu Vaccine and Egg Allergies in print or online must be granted by the author in writing.