In the past three weeks, New World screwworm has been confirmed in 11 animals in Texas, and one dog in neighboring New Mexico has also tested positive. Arizona has no confirmed cases at this time.
While Arizona is not currently experiencing an outbreak, now is the time for dog and cat owners to learn how screwworm infestations occur, what signs to watch for, and what steps can help reduce risk.
At Adobe Veterinary Center, we help Southern Arizona pet owners protect their animals through preventive care, early diagnosis, and treatment when health concerns arise. Understanding how screwworm infestations develop can help pet owners recognize potential problems and know when veterinary care may be needed.
Why Are Animal Health Experts Paying Attention to Screwworms?
For decades, New World screwworm was considered eradicated from the United States. However, the parasite has been moving northward through Central America and Mexico in recent years. On June 3, 2026, the U.S. Department of Agriculture confirmed the first U.S. case in nearly 60 years when screwworm was detected in a calf in Texas.
Since then, additional cases have been identified in Texas and New Mexico, including a confirmed case in a dog. These detections have prompted increased monitoring efforts and renewed attention to the importance of wound care, fly control, and early detection.
If you would like additional information about the current status of New World screwworm in the United States, the USDA maintains updated information through its Stop Screwworm program.
What Is a Screwworm?
New World screwworm is a parasitic fly that lays its eggs in open wounds and other openings on warm-blooded animals. Once the eggs hatch, the larvae burrow into living tissue and begin feeding.
Unlike ordinary maggots that feed on dead tissue, screwworm larvae feed on healthy, living tissue. Without treatment, they can cause significant tissue damage in a relatively short period of time.
The screwworm does not spread directly from animal to animal. An infestation requires both an open wound and exposure to the fly. That means pet owners have more control than many of the headlines suggest.
Good wound care, routine observation, parasite prevention, and fly control all play important roles in reducing risk.
Can Dogs and Cats Get Screwworms?
Yes. While recent news coverage has focused largely on livestock cases, dogs and cats can also develop screwworm infestations when flies lay eggs in wounds or other openings in the skin.
Potential risk factors include:
- Cuts and scratches
- Bite wounds
- Surgical incisions
- Hot spots
- Skin infections
- Draining wounds
- Areas of irritated or damaged skin
Pets that spend time outdoors may have greater exposure to flies, but any pet with an open wound or skin injury could potentially be affected.
Signs of Screwworms in Dogs and Cats
Because pets often hide discomfort, the earliest warning signs may be subtle. Contact Adobe Veterinary Center if you notice:
- A wound that worsens instead of healing
- A foul odor or unusual discharge from a wound
- Swelling or sensitivity that seems unusual
- Visible larvae within a wound
- A pet that seems lethargic, withdrawn, or not acting normally
Any wound that appears to be getting worse rather than better should be evaluated promptly.
What Should Pet Owners Do Right Now?
There are practical steps pet owners can take to help protect their animals:
- Keep dogs and cats current on veterinarian-recommended monthly parasite preventatives
- Check pets regularly for cuts, wounds, skin irritations, and hot spots
- Seek treatment promptly for wounds that are not healing normally
- Use appropriate fly-control measures around your home and property
- Monitor any healing wound closely for changes
Most importantly, do not ignore a wound that appears to be getting worse rather than better.
Traveling With Pets? Check Before You Go
Travel and movement requirements for animals are already changing as new screwworm cases are confirmed. Dogs and cats traveling across state lines or into Mexico may be subject to additional requirements depending on current regulations.
Because recommendations can change quickly, do not assume yesterday’s rules still apply today. If you are planning to travel with your pet, contact Adobe Veterinary Center before your trip so we can help you determine whether any current requirements may affect your plans.
Pet owners can also check the USDA Animal and Plant Health Inspection Service (APHIS) Pet Travel website for the latest travel requirements and updates:
If you plan to travel to or from Mexico with your dog, additional screwworm-related requirements may apply. Current information is available through the USDA APHIS Mexico Pet Travel page.
When Should You Contact Adobe Veterinary Center?
If a wound does not look right or is not healing the way it should, call us.
Early treatment is extremely important with screwworm infestations because larvae can damage healthy tissue quickly. Our team can evaluate the wound, determine the cause, and recommend appropriate treatment to protect your pet’s health and comfort.
We are tracking this situation closely and will continue to keep our clients informed as recommendations and requirements evolve.
Protecting Arizona’s Dogs and Cats
The recent cases in Texas and New Mexico are a reminder that paying attention to wounds, maintaining parasite prevention, and staying consistent with fly control are important steps every pet owner can take.
At Adobe Veterinary Center, we are committed to helping Southern Arizona pet owners keep their dogs and cats healthy. If you notice a wound that is not healing properly or have concerns about your pet’s health, contact our team. Early evaluation and treatment can make a significant difference.