Vaccines include ingredients to help them do their work. Each ingredient used to make a vaccine has a specific purpose. Certain ingredients, just like preservatives in foods, help keep vaccines safe from contamination and toxins that could make us sick.
Learn more about the two new Omicron (bivalent) vaccines, Pfizer and Moderna, which were recently authorized to be used as booster doses to help protect against the Omicron variants of the virus that causes COVID-19.