Some doctors in Alberta have criticized officials for not declaring a health emergency in the western province where measles infections are surging.

© Dave Chidley/Agence France-Presse — Getty Images

Dr. Monarez, who has been the acting head of the Centers for Disease Control and Prevention since President Trump took office, was the president’s second pick for the job.

© Tierney L. Cross/The New York Times

The health secretary ousted his chief of staff and a deputy chief of staff, both of whom were seen as practical and effective government veterans.

© Kenny Holston/The New York Times