The U.S. Centers for Disease Control and Prevention has appointed Retsef Levi, an MIT operations-management professor who has publicly questioned the safety of mRNA shots, to chair its COVID-19 immunization workgroup. The position will steer the Advisory Committee on Immunization Practices’ review of vaccine data and recommendations. CDC staff will not serve on the panel, a sharp break with past practice. Levi’s elevation follows Health and Human Services Secretary Robert F. Kennedy Jr.’s June decision to dismiss all 17 ACIP members and replace them with seven new appointees, several of whom have expressed skepticism about routine immunizations. Earlier this month the department also cancelled $500 million in federal grants for mRNA-vaccine research and withdrew blanket recommendations for COVID shots in healthy children and pregnant women. Vaccine manufacturers and public-health experts warn the administration’s broader strategy could shrink access to longstanding vaccines. Industry officials say Kennedy’s plan to expand the list of injuries covered by the Vaccine Injury Compensation Program could expose companies to litigation risks large enough to drive some products off the market. Internal resistance is growing. More than 750 HHS employees have sent a letter to Congress and the secretary urging him to stop spreading what they call medical misinformation, arguing that hostile rhetoric has endangered agency staff following an August shooting at CDC headquarters. The White House insisted policy decisions will continue to be based on “gold-standard science” and denied reports that COVID vaccines will be withdrawn in the coming months.