For Pet Owners

Adult NWS flies can lay hundreds of eggs in even minor scratches, bite wounds, and surgical incisions. As such, pet owners should monitor for:

• • Wounds that worsen quickly or fail to heal
  • Swelling or irritation around a wound
  • A foul odor, often described as decaying tissue
  • Visible larvae (maggots)
  • Excessive licking or chewing at an affected area
  • Signs of pain or discomfort

NWS can affect any warm-blooded animal, including dogs and cats, livestock, wildlife, and people. The greatest risk factor is the presence of an open wound.

Pets may be at increased risk if they:

• • Have cuts, scrapes, bite wounds, or other skin injuries
  • Are recovering from surgery
  • Have skin infections or other draining wounds
  • Spend time outdoors where injuries may occur
  • Are not receiving veterinarian-recommended parasite preventatives

Stray or unowned dogs and cats are likely at higher risk of NWS due to fighting injuries such as bites and abscesses, complications from recent spay or neuter procedures, skin infections, or injuries associated with giving birth. Limited access to veterinary care and preventative medications also increase their risk of infestation.

Preventing NWS infestation starts with routine care, observation, and awareness. The most effective ways to reduce the risk of infestation include:

• • Checking pets daily for cuts, scrapes, or other wounds
  • Cleaning and treating wounds promptly and until completely healed
  • Monitoring surgical incisions daily during recovery
  • Keeping pets up to date on veterinary care and parasite preventatives
  • Seeking veterinary attention promptly if a wound appears abnormal or is not healing as expected

Because this is not a disease — it is an insect infestation — when the insects are removed, the animal typically recovers, especially if attention is given early.

In addition, the U.S. Food and Drug Administration has conditionally approved several antiparasitic products that prevent and treat NWS in multiple species. Visit tx.ag/approvedmeds to learn more.

If you suspect New World Screwworm in your dogs or cats, do not wait — prompt veterinary care is essential.

If your pet has a rapidly worsening wound, visible larvae, a foul odor, or any other signs of possible infestation, early diagnosis and treatment will greatly improve the likelihood of a successful outcome:

• • Immediately isolate suspected animals
  • Contact your local veterinarian

Additional educational resources:

• • NWS: What Community Cat Caregivers Need to Know
  • NWS: What Animal Shelters Need to Know
  • NWS: What K9 Handlers Need to Know
  • Texas A&M AgriLife Extension Service
  • Texas Animal Health Commission
  • Texas A&M VMBS Pet Talk: Protecting Pets from New World Screwworm
  • Screwworm.gov (USDA APHIS)
  • New World Screwworm Outbreak (CDC)
  • New World Screwworm: Info for Veterinarians (FDA)

Conduct daily hands-on wound checks. Cover wounds whenever practical and keep all wounds clean and dry. Protect and/or isolate until healed, all animals with:

• • Surgical incisions
  • Hot spots
  • Skin, foot or other wounds
  • Ear injuries
  • Tick attachment wounds

If pets are housed outdoors or there is limited indoor housing space, prioritize:

• • Pets with any preexisting skin, eye or ear issues
  • Pets with skin or ear injuries, infections
  • Pets with wounds (whether or not they are surgically repaired or small)

If your kennel or housing area is open air:

• • Increase air flow with fans
  • Install fine insect screening around kennel and housing areas
  • Add screened shade structures
  • Add fly curtains at housing entrances if possible
  • Install fly traps or fly aversion in areas where pets are kenneled, resting

Pet owners in the border area or quarantine zones should have a standard operating procedure if suspicious larvae are found:

• • Isolate animal to treat
  • Photograph lesion
  • Contact veterinarian
  • Administer Nexguard/Simparica or Capstar
  • Preserve larvae samples (put in 70% alcohol to kill)
  • Document animal origin and movement history

• • Include a visual wound inspection after search activities at the end of the day.
  • Actively record and monitor all pets daily with cuts, scrapes and abrasions.
  • Apply fly prevention products and cover wounds if possible.
  • Keep all wounds clean and dry and monitor until fully healed.

Pet owners should learn to recognize and to immediately report:

• • Enlarging wounds
  • Foul-smelling wounds
  • Bloody wound drainage
  • Unexplained pain
  • Head shaking
  • Excessive licking
  • Visible larvae