USDA updated its unified New World screwworm response hub on September 21, 2026, giving U.S. animal owners one place to check confirmed detections, prevention guidance, travel rules, and reporting instructions. The agency says the current risk to animals and people in the United States is very low, but pet owners—especially those in or traveling through affected areas—should inspect wounds and contact a veterinarian immediately if they see maggots, a rapidly worsening wound, drainage, or a foul odor.

This is not a reason to panic or treat every fly as dangerous. New World screwworm is not contagious, and not every maggot infestation is caused by this species. The practical message is to notice suspicious wounds early and let veterinary and animal-health professionals identify the cause.

What happened?

The U.S. Department of Agriculture’s Animal and Plant Health Inspection Service consolidated federal screwworm information at Screwworm.gov, with the main response page last modified on September 21. The hub now connects pet owners, veterinarians, travelers, livestock producers, wildlife officials, and public-health agencies to the same current-status and reporting resources.

The update matters because New World screwworm has returned to parts of the region after decades of control. The CDC says USDA confirmed the first U.S. animal case in the current outbreak on June 3, 2026. Federal agencies have since maintained surveillance, animal-movement controls, reporting systems, and sterile-fly releases. USDA’s dashboard tracks confirmed animal cases by county, state, species, confirmation date, and status.

For pet owners, the most important change is not a new nationwide warning. It is easier access to verified information during an active animal-health response. USDA continues to state that the overall U.S. risk is very low, and the CDC reported no locally acquired human infestations as of its August 11 situation update.

What is New World screwworm?

New World screwworm is a fly whose larvae feed on the living tissue of warm-blooded animals. A female fly can lay eggs on an open wound or around a body opening such as the nose, ears, eyes, mouth, or genital area. After hatching, the larvae burrow into tissue and can make the wound larger and deeper.

Dogs, cats, livestock, wildlife, birds, and people can be affected. A scrape, tick bite, surgical incision, irritated skin, or another small break in the skin can create an opening. Pets that spend substantial time outdoors in an affected area or travel to a region with active cases deserve closer checks, but any suspicious wound should be evaluated regardless of location.

USDA emphasizes two facts that help keep the risk in perspective:

  • It is not contagious. An infestation does not spread directly from one pet to another or from a pet to a person. A screwworm fly must lay eggs on a wound or body opening.
  • Not every maggot is New World screwworm. Other fly species can cause myiasis. Laboratory or expert identification is needed to confirm the species.

Which U.S. pet owners should pay the closest attention?

All owners should know the warning signs, but vigilance is especially important for:

  • Dogs and cats living in or visiting an area listed on USDA’s current-status map.
  • Outdoor, working, hunting, or farm pets that are more likely to develop unnoticed cuts.
  • Pets with recent surgery, skin disease, bite wounds, sores, or draining injuries.
  • Animals traveling to or returning from Mexico, Central America, or another location with active cases.
  • Households near livestock or wildlife activity in an affected region.

Owners planning international travel should review official import requirements before departure and again before returning. Our U.S. dog-travel guide covers broader preparation, but current USDA and CDC rules take priority whenever an animal-health alert is active.

Warning signs in dogs and cats

USDA advises owners to focus on the animal and its wounds rather than trying to identify adult flies. Released sterile flies may look like wild flies, and many harmless species are visually similar.

Contact a veterinarian immediately if you notice:

  • Maggots or clusters of pale eggs in or around a wound.
  • A wound that is enlarging, draining, bleeding, or failing to heal.
  • A strong foul or decaying odor from the wound.
  • Larvae around the nose, ears, eyes, mouth, genital area, or another body opening.
  • Sudden pain, persistent licking, head shaking, agitation, hiding, depression, or isolation.
  • Reduced appetite or an unusual drop in activity alongside a suspicious wound.

These signs can also occur with other urgent conditions. Waiting to see whether the problem resolves can allow tissue damage or secondary infection to worsen. Do not apply livestock pesticides, insecticides, essential oils, or leftover medications to a pet. Treatment and any sample collection should be directed by a veterinarian.

What pet owners should do now

1. Check your pet after outdoor activity

Run your hands over the coat and inspect the ears, face, paws, skin folds, belly, tail area, and any known wound. Long-coated pets may need the fur gently parted to see the skin. Outdoor dogs deserve an additional check after hiking, hunting, ranch work, or time in brush.

2. Keep wounds clean and follow veterinary instructions

Small wounds still matter. Ask your veterinarian how to clean and protect an injury, and schedule a recheck if it is not improving. Do not seal a dirty or draining wound under a home bandage without professional guidance.

3. Use only veterinarian-recommended fly control

Products labeled for livestock may be unsafe for dogs or cats, and dog products containing certain insecticides can be dangerous to cats. Your veterinarian can recommend an appropriate product based on species, age, weight, health, and local risk.

4. Confirm travel and movement requirements

Pets and service animals entering the United States from affected countries must meet USDA and CDC import requirements. Rules can change during an outbreak, so do not rely on an old checklist or a social-media post. Verify the requirements with the agencies and your airline close to the travel date.

5. Have an emergency-care plan

Save the phone numbers for your regular veterinarian and the nearest emergency clinic. If cost is a concern, review your options before a crisis; our overview of pet insurance in the United States explains common coverage limitations and waiting periods. Insurance should never delay urgent evaluation.

How to report a suspected case

For a dog, cat, or other companion animal, USDA’s instruction is straightforward: contact a veterinarian to evaluate the pet. The veterinarian can coordinate required reporting and diagnostic identification with state animal-health officials and USDA APHIS.

USDA’s reporting page provides separate routes for livestock, wildlife, pets, and people. Do not transport a potentially infested pet over a long distance without first calling the clinic; staff may give arrival and isolation instructions.

If a person has a suspicious wound or visible larvae, contact a healthcare provider. The CDC says human cases require prompt medical evaluation and public-health reporting. This article’s guidance for pets is not a substitute for human medical advice.

What the federal response means for pet owners

USDA says its response includes surveillance, inspections, animal-movement controls, public outreach, and the production and targeted release of sterile male flies. When sterile males mate with wild females, the resulting eggs do not hatch, interrupting the life cycle without asking pet owners to identify or kill flies themselves.

The new federal hub also separates verified guidance from rumors. USDA states that screwworm is not a food-safety issue, does not spread like a virus, and should not be diagnosed by appearance alone. That distinction matters because panic can lead owners to misuse pesticides or mistake an unrelated wound for a confirmed infestation.

For ongoing routine care, owners can also review the site’s dog health resources, dog care articles, and cat care articles. During this response, however, USDA, CDC, state animal-health officials, and your veterinarian remain the authoritative sources.

Frequently asked questions

Can New World screwworm spread from my pet to me?

Not directly. USDA says it is not contagious between animals or from animals to people. A person or animal becomes infested when a fly lays eggs on a wound or body opening.

Should I take my pet to the veterinarian for any maggots?

Yes. Not all maggot infestations are New World screwworm, but any maggots in a wound need prompt veterinary evaluation. Expert identification is required, and treatment should not wait for an owner to determine the species.

Is there a preventive screwworm medicine for pets?

Do not give or apply a product unless your veterinarian recommends it for that pet. Federal drug authorizations and treatment options may be specific to species and circumstances. Wound prevention, regular checks, safe fly control, and early veterinary care are the appropriate owner actions.

Sources

Veterinary disclaimer: This article provides general news and safety information. It does not diagnose an infestation or replace examination and treatment by a licensed veterinarian.

Featured image: Photo by Karsten Winegeart on Unsplash.