In his confirmation hearings, Robert F. Kennedy Jr. told U.S. senators that he would not cut funding for vaccine research or change the nation's official vaccine recommendations. He did both.

The recent request goes against decades of precedent, and puts noncitizens at further risk of immigration enforcement actions.

Booz Allen’s stock slumped over 11% on Monday after the contracts were cancelled.

The new directive asks workers to check the backgrounds of foreign nationals collaborating with the department’s scientists for evidence of “subversive or criminal activity.” Their names are being sen...