As fired and retired scientists rallied outside in the Atlanta heat, an advisory panel that Robert F. Kennedy Jr. handpicked to replace experts he’d fired earlier met inside the Centers for Disease Control and Prevention’s headquarters to plan a more skeptical vaccine future.

The reconstituted C.D.C. panel will revisit the standard vaccination schedule. The former head of an anti-vaccine group is now a special federal employee.

During his Senate confirmation hearings, Health Secretary Robert F. Kennedy Jr. suggested he wouldn’t undermine vaccines. “I am not going to go into HHS and impose my preordained opinions on anybody at HHS,” he said. “I’m going to empower the scientists at HHS to do their job and make sure that we have good science that is evidence based.”