Signs Your Pet Might Have New World Screwworm

New World screwworm (NWS) is a parasitic fly larva (maggot) that can burrow into and feed on the flesh of a living animal. NWS can infest warm blooded animals, including livestock, pets, wildlife, birds, and in rare cases, people. Adult female flies lay eggs in wounds and body openings of live animals.

Signs of New World screwworm

• Visible maggots or eggs: Look for maggots or egg masses in or around wounds or sores, or in the ears, nose, eyes, mouth, or genital areas of live animals.
• Worsening wounds: Painful skin wounds or sores that enlarge rapidly, deepen, or bleed within a few days.
• Foul odor: A distinct smell of decay or rotting flesh coming from the site of infestation.
• Behavioral changes: Irritated behavior, head shaking, constant licking or biting at the impacted area, depression, or animals isolating themselves.

Contact a veterinarian if you suspect your pet has a New World screwworm case. Cover the wound before heading to the veterinarian to avoid dropping any materials from the wound.

Image

Risk factors

• Your pet might be more likely to get New World screwworm if you are in areas where the flies are present. Head to our screwworm resources page and screwworm.gov to learn more.
• Animals that have deep skin folds and matting of hair around their face can provide moist sites for New World screwworm to set up.
• Spend lots of time outdoors. Have any open wounds or sores, no matter how small.

Prevention tips

• Recognize signs of New World screwworm in pets.
• Proactively protect pets from ticks and fleas. Their bites are enough to attract New World screwworm.
• Protect pets from injury caused by sharp objects or aggressive animals.
• If wounded or recovering from birth or surgery, keep animals indoors and wounds clean