A resurfaced video of RFK Jr. from 2023 shows him falsely linking the polio vaccine to other diseases. Ari Melber fact checks the heath secretary's claims.

Critics say Kennedy is ordering a review of childhood vaccines to stoke skepticism, risking the spread of disease.

Health and Human Services Secretary Robert F. Kennedy Jr. fired all 17 members of the Centers for Disease Control and Prevention’s vaccine advisory panel, claiming it “has been plagued with persistent conflicts of interest and has become little more than a rubber stamp for any vaccine.