Mo. Rev. Stat. § 192.460

Whenever the department of health and senior services finds that an emergency exists requiring immediate action to protect the public health or welfare, it may issue an order reciting the existence of an emergency and requiring that such action be taken as it deems necessary to meet the emergency. The order shall be effective immediately. Any person to whom the order is directed shall comply therewith immediately, but on application to the department shall be afforded a hearing within ten days. On the basis of the hearing the department shall continue such order in effect, revoke it, or modify it.