510 ILCS 50/3
Upon its becoming known to the Department that any animals are infected, or suspected of being infected, with any contagious or infectious disease, or contaminated with any chemical or radiological substance, the Department shall have the authority to quarantine and to cause proper examination thereof to be made. If such disease is found to be of a dangerously contagious or dangerously infectious nature, or the contamination level is such that may be harmful to humans or other animals, the Department shall order such diseased or contaminated animals and such as have been exposed to such disease or contamination, and the premises in or on which they are, or have recently occupied, to be quarantined. The Department shall also have the authority to issue area-wide quarantines on animals and premises in order to control the spread of the dangerously contagious or infectious disease and to reduce the spread of contamination. The Department may, in connection with any such quarantine, order that no animal which has been or is so diseased, contaminated, or exposed to such disease or contamination, may be removed from the premises so quarantined and that no animal susceptible to such disease or contamination may be brought therein or thereon, except under such rules as the Department may prescribe.
510 ILCS 50/3