Vaccine ingredients

Vaccines are usually made of six main components or ingredients: 

• antigens that train the body’s immune system to recognise and respond to the bacteria or virus of interest/concern
• adjuvants that help strengthen the immune system’s response to the antigen so less vaccine or fewer doses are needed (example: aluminium salts)
• stabilisers that help keep the important components of the vaccine working properly (example: gelatin)
• preservatives that protect the vaccine from getting contaminated with harmful bacteria or fungi (example: alcohol)
• residues (or residual by-products) that are present in extremely small amounts in the vaccine after the manufacturing process (example: yeast)
• diluents that are used to mix with the powdered or pellet-form of the vaccine to create a liquid vaccine so it can be injected (example: sterile water).

To read more about each component, visit: 

• Types of vaccine ingredients – Children's Hospital of Philadelphia
• What is in the vaccines – SKAI

To find out what components or ingredients are in a specific vaccine, visit: 

• Components of immunisation products used in Australia – Australian Immunisation Handbook
• Product information sheet for the vaccine of interest – Therapeutic Goods Administration

For more information about specific component or ingredient in vaccines, visit: 

• Specific ingredients – Children's Hospital of Philadelphia