Ask The Expert
November 18, 2013
When administering MMR vaccine, is there any concern with patients that have either egg allergy, latex allergy, or gelatin allergy? How would you go about testing for these allergens in MMR vaccine?
By Dr. John Kelso
Measles and mumps vaccines are grown in chick embryo fibroblast cultures and contain negligible or no egg protein. MMR vaccine can be administered to children with egg allergy without any special precautions.
The ‘‘rubber’’ in vaccine vial stoppers or syringe plungers can be either dry natural rubber (DNR) latex or synthetic rubber. Those made with DNR pose a theoretic risk to the patient who is allergic to latex, although the likelihood of such a reaction is exceedingly small. The MMR vaccine marketed in the United States does not contain latex in the packaging. The latex content of vaccine packaging can be found at http://www.cdc.gov/vaccines/pubs/pinkbook/downloads/appendices/B/latex-table.pdf. There are commercial assays available for specific IgE antibody to latex.
Gelatin is added to many vaccines including MMR as a stabilizer and has been shown to be responsible for many anaphylactic reactions. Some patients who are allergic to gelatin will react to the ingestion of gelatin, but others react only when the gelatin is injected with the vaccine. Patients who report allergic reactions to the ingestion of gelatin should be evaluated by an allergist prior to the administration of any gelatin-containing vaccine. There are commercial assays available for specific IgE antibody to gelatin. Also a crude (non-FDA approved) extract of gelatin can be prepared by dissolving 1 teaspoon (5 g) of any sugared gelatin powder (for example Jell-O) in 5 mL of normal saline.
If a patient has already had an apparent allergic reaction to the administration of MMR vaccine, it would be appropriate to skin test with the vaccine prick full-strength and if negative intradermal diluted 1:100.
Even in a patient who is allergic to gelatin or who has had an allergic reaction to a prior dose of MMR vaccine and has a positive vaccine skin test, if additional doses of the vaccine are required, consideration can be given to administering the vaccine in graded doses under observation prepared to treat any reaction as follows: For a vaccine in which the full normal dose volume is 0.5 mL, give the following doses at 15-minute intervals as tolerated: 0.05 mL 1:10 dilution, 0.05 mL full-strength, 0.1 mL full-strength, 0.15 mL full-strength, 0.2 mL full-strength.
John Kelso, MD
Division of Allergy, Asthma and Immunology
Scripps Clinic - San Diego, CA, USA
Note: Please read disclaimer. Ask the Expert is for licensed physicians only.