Vaccine Safety
Concerns related to the safety of vaccines vary. In this section of our website, you will find that we address a variety of these concerns. For convenience we have grouped them as shown below. By clicking through to each section, you will find out more about what topics we cover. If you can’t find something, you can try using the search tool at the top right of each webpage or you can contact us using this form.
![Needle and vial closeup](/sites/default/files/styles/landscape_150_3x2_160x107_1x/public/2024-07/Photo-Restricted-VEC-needle-vial-closeup-2624x1720-v01.jpg?itok=3t6kraLY)
Vaccine Ingredients
Many questions about vaccines revolve around the ingredients in the vaccine vial. Learn why certain ingredients are used, the quantities present in vaccines, and the safety of vaccine ingredients.
![Girl with insomnia](/sites/default/files/styles/landscape_150_3x2_160x107_1x/public/2024-07/Photo-Restricted-VEC-child-with-insomnia-2624x1720-v01.jpg?itok=9XSbRXRk)
Vaccines and Other Conditions
Most people agree that vaccines protect against the diseases they are meant to protect against. However, some people wonder whether vaccines are also causing other conditions in exchange for that protection, such as asthma, autism and multiple sclerosis.
![Black man looking at cell phone](/sites/default/files/styles/landscape_150_3x2_160x107_1x/public/2024-07/Photo-Restricted-VEC-black-man-looking-cell-phone-2624x1720-v01.jpg?itok=77DCspte)
Other Vaccine Safety Concerns
This section addresses safety concerns not related to ingredients or other conditions, including questions about vaccine dosing, fevers, the blood-brain barrier (BBB), and antibody-dependent enhancement (ADE).
![Magnifying glass and wooden figures](/sites/default/files/styles/landscape_150_3x2_160x107_1x/public/2024-07/Photo-Restricted-VEC-magnify-glass-wooden-figures-2624x1720-v01.jpg?itok=jlsXfd3j)
Vaccine Safety References
This library offers summaries of key scientific papers that have evaluated some vaccine safety concerns.
Reviewed on July 17, 2024