06/20/2026
New World Screwworm: What Pet Owners Should Know
Thank you to our friends at BISSELL Pet Foundation for sharing important information about New World screwworm!
New World screwworm is a type of fly larva that can infest open wounds on living animals. Unlike most fly larvae that feed on dead tissue, screwworm larvae can burrow into wounds and cause serious damage if not treated quickly.
The most important things to know:
✅ It is serious, but it is treatable.
✅ It is not contagious like a virus or illness passed pet-to-pet.
✅ Early detection and veterinary care make a big difference.
✅ Pet owners should check wounds carefully, especially after outdoor time or travel to affected areas.
What to watch for:
• Open wounds that are not healing
• Maggots or movement in a wound
• A foul odor from a wound
• Pain, swelling, bleeding, or worsening sores
• Pets acting painful, restless, or unusually uncomfortable
What should you do?
If you see maggots or a concerning wound, contact your veterinarian right away. Do not wait. Identification and proper treatment are important. It is treatable, it is not contagious, and there are FDA-approved solutions available right now: Nexgard, Capstar, and Credelio. Early detection is the key, which is something every pet owner and shelter can do.
Pet owners traveling from or through affected areas should also be aware that some states may have temporary animal transport requirements or restrictions, including recent health certificates confirming pets are screwworm-free.
At this time, the greatest concern is in border states where cases have been confirmed, but awareness and preparation matter everywhere. For shelters, rescues, and pet owners, the best tools are prevention, wound care, fly control, careful observation, and fast veterinary follow-up when something looks wrong.
Thank you again to BISSELL Pet Foundation and their Animal Incident Management team for staying ahead of this issue and helping to provide support to pets, shelters, and communities.
