An adjuvant is classically defined as “an ingredient of a vaccine that helps create a stronger immune response in the patient’s body.”
The most commonly used adjuvant in vaccines in the United States is aluminum. Monophosphoryl lipid A is another adjuvant that is used in one brand of HPV vaccine.
Not all vaccines have adjuvants though.
Adjuvant 65 is a water-in-oil emulsion that was tested in flu vaccines in the 1960s. Another component of Adjuvant 65, Arlacel A, was found to cause cancer in mice, so this adjuvant was never actually licensed to be used in any US vaccines.
That well known fact hasn’t kept some people from blaming Adjuvant 65 for causing an epidemic of peanut allergies, since it also contained peanut oil.
For more information:
- Antivaccine lies–peanut oil and vaccines
- Anti-Vaccination Conspiracy Theories
- CDC – Vaccine Adjuvants Concerns
- Vaccine Ingredients – Corn and Peanut Oils