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

An attenuated vaccine (or a live attenuated vaccine, LAV) is a vaccine created by reducing the virulence of a pathogen, but still keeping it viable (or "live").

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

In public health, contact tracing is the process of identifying people who may have been exposed to an infected person ("contacts") and subsequent collection of further data to assess transmission.

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

HIV/AIDS is a global pandemic caused by the human immunodeficiency virus (HIV).

John Franklin Enders (February 10, 1897 - September 8, 1985) was an American biomedical scientist and Nobel Laureate.

Maurice Ralph Hilleman (August 30, 1919 - April 11, 2005) was a leading American microbiologist who specialized in vaccinology and developed over 40 vaccines, an unparalleled record of productivity.