http://www.phac-aspc.gc.ca/publicat/ccdr-rmtc/96vol22/dr2214ea.html

Vaccines that contain small quantities of egg protein can cause hypersensitivity reactions in some people with egg allergy.  [So let's take this one step further. If it can cause an allergic reaction if you already have an egg allergy, it also can be the first exposure for the baby and CAUSE the allergy! - bfg]

Adverse reactions are more likely with vaccines, such as yellow fever and influenza vaccines, that are grown in embryonated eggs. In contrast, measles and mumps vaccine viruses, which are most widely used in Canada, are grown in chick-embryo cell culture. Even after extensive purification, final vaccine products may contain trace quantities of avian proteins resembling proteins present in hens' eggs (1,2) . Anaphylaxis after administering measles-containing vaccines is rare and has been reported in individuals with anaphylactic hypersensitivity to eggs as well as those with no history of egg allergy. In some of these instances, allergy to neomycin (3,4) or gelatin (5) was hypothesized but, in most cases, no allergen was identified (6-8) . [or it could be a reaction to any of the other food proteins in the vaccine - bfg]

skin testing was abandoned after the first 120 children because of its lack of predictiveness (16)

In addition, a total of 38 anaphylactic reactions after measles immunization have been reported in the literature in individuals without a history of egg allergy; [But didn't they have a history of being vaccinated with a vaccine that contained egg protein? - bfg]

As previously recommended by NACI, all immunizations should be administered by persons capable of managing vaccine-associated adverse reactions such as anaphylaxis and should take place in appropriate facilities.