06/10/2026 | Press release | Distributed by Public on 06/11/2026 08:31
The Colorado State Veterinarian proposed, and the Commissioner of Agriculture adopted, upon the Colorado Agricultural Commission's recommendation, an emergency rule to control the spread of New World Screwworm (NWS) into Colorado. This action follows detections of NWS in Texas and New Mexico.
NWS is a threat to all warm-blooded animals, including livestock, pets, wildlife, and occasionally people. This emergency rule is part of the Colorado Department of Agriculture's One Health response to the NWS. Vigilance in monitoring for myiasis is critical, and early detection is key. A NWS infestation can be treated, but early detection is important to ensure animals can recover. The New World Screwworm does not pose a food safety risk, and the US food supply continues to be safe.
"This emergency rule is a vital step in safeguarding the health and well-being of all of Colorado's animals, including livestock, companion animals, and wildlife," said Colorado State Veterinarian Dr. Maggie Baldwin. "By working with veterinarians and animal owners to implement these protective measures, we can mitigate the impact of the New World Screwworm on Colorado animals. By strengthening our requirements for veterinary inspections before animal movement into Colorado, we are ensuring a safer, healthier future for all animals across our state."
The rule stipulates that no animal with NWS myiasis may enter Colorado. It also follows USDA's NWS Continuity of Business guidance which requires specific movement protocols for livestock originating from an NWS Infested Zone. The USDA defines the Infested Zone as a 20 km (12 mile) radius from a confirmed detection.
The emergency rule includes the following restrictions on all warm-blooded animals coming to Colorado from Infested Zones:
Additionally, the emergency rule establishes critical protections for cats and dogs, requiring additional inspection protocols within 5 days prior to their entry into Colorado if they originate from states with active NWS Infested Zones. Owners and facilities must ensure companion animals are examined for any signs of the screwworm, particularly open wounds, which must be treated according to authorized guidelines before movement. This preventative measure is essential to curbing the potential spread of this pest among household pets.
Livestock and pets traveling into Colorado from areas that are not in the Infested Zone must continue to follow our state's animal import requirements.
CDA is collaborating with facilities licensed through the Pet Animal Care and Facilities Act (PACFA) program to implement these new requirements. Through proactive education and outreach, CDA is providing resources and guidance to help licensees implement increased safety protocols and maintain the highest standards of biosecurity. The PACFA program is working in partnership with licensed shelters, rescues, and boarding facilities to ensure they are well-equipped to protect the animals in their care from the threat of New World Screwworm.
The Colorado State Veterinarian's Office is holding an informational webinar on Thursday, June 11 at 6 pm that is free and open to the public. You can register at ag.colorado.gov/events or directly via Zoom.
Violations of this rule can lead to orders to return animals to the origin or quarantine of the receiving premises and potential legal action. For more information, visit ag.colorado.gov/NWS.