Paul Offit knows vaccines. A trained doctor, he spent 26 years working in pediatric infectious disease and studying the rotaviruses before ultimately creating the strain that became the RotaTeq vaccine.

Among the eight people Robert F. Kennedy Jr. announced would make up his new group of outside vaccine advisers to the US Centers for Disease Control and Prevention are an emergency physician who posted Islamophobic commentary on social media and two doctors who were paid to provide expert testimony in trials against a vaccine maker.

The Department of Health and Human Services sent Congress a document to support Secretary Robert F. Kennedy Jr.’s decision to change federal vaccine recommendations that cited unpublished or disputed studies and misrepresented other findings,