US Health and Human Services Secretary Robert F. Kennedy Jr. has fired two of his top aides in an abrupt shakeup of the leadership at the nation’s sprawling health department, two people familiar with the matter told CNN.

Health Secretary Robert F. Kennedy Jr. has shaken up his top staff just months into his tenure atop the Health and Human Services Department. Why it matters: Kennedy's time atop the huge federal health bureaucracy has already been marked by tensions with the White House over the measles outbreak,