Frequently Asked Questions about Adjuvants

• What is a vaccine adjuvant?
• What are some examples of adjuvants?
• How long have adjuvants been used in vaccines?
• Why are vaccine adjuvants used?
• Which childhood vaccines contain adjuvants?
• Which childhood vaccines do not contain adjuvants?

What is a vaccine adjuvant?

A vaccine adjuvant is a substance that is added to the vaccine to increase the body's immune response to the vaccine.

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What are some examples of adjuvants?

Aluminum gels or aluminum salts are the only vaccine adjuvants currently licensed for use in the United States. Small amounts of aluminum are added as an adjuvant to help stimulate better responses to vaccines. Aluminum is one of the most common metals found in nature and is present in air, food, and water.

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How long have adjuvants been used in vaccines?

Aluminum salts, such as aluminum hydroxide, aluminum phosphate, and aluminum potassium sulfate have been used in vaccines for more than 70 years. Aluminum salts were used in the 1930s, 1940s, and 1950s with diphtheria and tetanus vaccines and were found initially to enhance immune responses to protect against tetanus and diphtheria after immunization.

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Why are vaccine adjuvants used?

Vaccine adjuvants improve the body's immune response and often allow for smaller amounts of the inactivated virus or bacterial components (the parts of vaccines that prompt an immune response) to be used in the production of the vaccine.

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Which childhood vaccines contain adjuvants?

The adjuvant aluminum is present in U.S. childhood vaccines that prevent hepatitis A, hepatitis B, diphtheria-tetanus-pertussis (DTaP, Tdap) Haemophilus influenzae type b (Hib), human papillomavirus (HPV) and pneumococcus infection. This adjuvant has been used safely in vaccines for decades.

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Which childhood vaccines do not contain adjuvants?

Live attenuated (weakened) viral vaccines that prevent measles, mumps, rubella, chickenpox, and rotavirus do not contain adjuvants. An inactivated (non-live) vaccine that prevents polio (inactivated polio vaccine, or IPV) does not contain adjuvant. Seasonal influenza vaccines used in the United States do not contain adjuvants.

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