President Donald Trump's first week in office came with big changes to U.S. health agencies, including the pausing of all external communications and banning travel.

The Centers for Disease Control and Prevention is going dark, along with other federal agencies within the umbrella of the U.S. Department of Health and Human Services. This week, the returning Trump administration told these agencies to stop talking to the public—for how long, no one knows.

The Trump Administration has frozen many federal health agencies’ communications with the public until at least the end of the month.