() President Donald Trump has ordered a “blackout” for federal health agencies, banning them from publishing external communication.

Agencies such as the Centers for Disease Control and Prevention, the Food and Drug Administration, the National Institute for Health and the Department of Health and Human Services will not be allowed to publish scientific reports, issue health advisories or update their websites.

The blackout, first reported by the Washington Post, comes at a time when experts are raising the alarm about public health concerns.

During a change in administration, it’s not uncommon for agencies to pause external communications. However, the blackout comes at a time of concern over public health issues and as Robert F. Kennedy Jr., nominated for Health and Human Services secretary, faces a potentially lengthy confirmation.

CNN reported that a follow-up memo specified the blackout is set to last through Feb. 1, and includes public speaking engagements and communications with lawmakers. Communications deemed urgent, such as recall notices or that are required by law, are exempt but higher-ups must be notified.

Another issue of concern is the increased spread of bird flu. The virus has been rapidly spreading among birds, wreaking havoc on the poultry industry, and a strain has been circulating among livestock, as well.

There have also been cases of bird flu reported in humans. The majority of cases have been reported in farm workers, though there have also been cases in which it’s less clear how it was contracted.

While continuing to stress that the risk to the public is low and there is no evidence of human-to-human transmission, the CDC recently advised hospitals to speed up testing for bird flu in admitted patients, urging subtype tests for those positive for influenza A be done within hours of admission.

A blackout would cut off such advisories and recommendations, leaving the public and health care professionals in the dark about new developments.

The Senate has yet to set a confirmation hearing date for Kennedy, even as it hurries to push through other Trump nominees. It’s not clear whether this would impact the length of the blackout.

Kennedy’s nomination has been controversial even among Republicans, with Sen. Mitch McConnell, R-Ky., a polio survivor, criticizing efforts by a lawyer working for Kennedy to revoke approval of the polio vaccine.

A group associated with former Vice President Mike Pence has also begun running a series of ads urging Republican senators to oppose Kennedy’s nomination.

Other Republican senators, however, including Sen. Ron Johnson, R-Wis., and Sen. John Cornyn, R-Texas, have expressed support for Kennedy. Some of Kennedy’s critics have also supported aspects of his platform, including efforts to reduce some of the ingredients used in processed food.