Lin Chen, a Harvard Medical School associate professor at Mount Auburn Hospital and a specialist in infectious disease, helped shape recommendations on vaccines until the process was dismantled by U.S. Secretary of Health and Human Services Robert F. Kennedy Jr. On June 9, Chen and all sixteen of her colleagues on the Advisory Committee on Immunization Practices (ACIP), the group that makes vaccine recommendations to the CDC, were dismissed. Chen had contributed to ACIP’s work for more than ten years. “The ACIP process is transparent. It’s always been nonpartisan until the past few months," Chen said. "And it’s always based on evidence, on scientific data.” Now, Chen worries about the future of the U.S. health care infrastructure and the spread of preventable diseases. She anticipates confusion as states consider formulating their own vaccine recommendations. There is also concern about loss of insurance coverage for some vaccines. “It’s just one of the steps toward dismantling the...