Anaphylaxis is a severe and potentially life-threatening allergic reaction that occurs rapidly and affects multiple body systems.

The Centers for Disease Control and Prevention (CDC) is a national public health agency in the United States.

The European Medicines Agency (EMA) is an agency of the European Union (EU) in charge of the evaluation and supervision of pharmaceutical products.

Measles is a highly contagious viral infection caused by the measles virus.

Measles vaccine protects against becoming infected with measles.

The MMR vaccine is a vaccine that helps protect individuals from three major diseases: measles, mumps, and rubella.

Mumps vaccines are vaccines which prevent mumps.

The National Institutes of Health (NIH) is an agency of the United States Department of Health and Human Services.