Another name for the diphtheria-tetanus-pertussis vaccine (for children).

A preparation which may be added to a vaccine to improve the immune response to the vaccine.

The diphtheria

An unwanted or unexpected event after a vaccine is given, which may be caused by the vaccine, or may occur by chance after immunisation. Adverse events may be at the site of the injection, or be a general illness or allergic reaction.

A sudden and severe allergic reaction, which results in a serious fall in blood pressure, and may cause unconsciousness and death if not treated immediately.

Micro-organisms (small living organisms that can only be seen with a microscope) smaller than a blood cell but bigger than a virus. Examples of infections caused by bacteria are diphtheria

A person who has an infection which, although not necessarily causing symptoms, may still be active and may spread to others; the carrier state may last for years; an example of infections that can result in the carrier state is hepatitis B

A vaccine that contains more than one component designed to immunise against two or more diseases (e.g. dTPa, MMR or dTPa-HepB-Polio-Hib).

Some bacterial vaccines (eg. Hib and pneumococcal conjugate vaccines) are made from the chemical linking (conjugation) of a tiny amount of the ‘sugar’ (correctly known as the polysaccharide) that makes up the cell coat of the bacteria with a protein molecule, in order to improve the immune response to the vaccine.

A reason why a vaccine or drug must not be given.