Can my pet get New World screwworm? Here’s what to know about keeping them safe

The resurgence of the New World screwworm, a flesh-eating parasitic fly with the potential to wreak havoc on the cattle industry, has drawn headlines as cases of infected cows in Texas grow. 

But it’s not just cows these New World screwworms pose a threat to. 

The U.S. Department of Agriculture on Thursday reported a case of New World screwworm in a dog in Lea County, New Mexico. An initial news release from the USDA, that was later corrected, said the case was reported in Andrews County, Texas, on the New Mexico border. The USDA also said it is investigating the dog’s travel history but did not immediately respond to a request for comment. 

The USDA and state partners are working to halt the resurgence by breeding and releasing sterile male flies to minimize the amount of fertilized eggs. 

Here’s what to know on keeping your pets safe. 

The New World screwworm is a parasitic fly that lays eggs inside open wounds and bodily openings including eyes, ears, mouths, noses and reproductive areas, according to the CDC. These eggs hatch into screwworm larvae, which feed on living flesh or tissue for around seven days before dropping to the ground, burrowing into soil and re-emerging as adult New World screwworm flies.  

Related: What to know about New World screwworm flies – and what’s at stake for Texas livestock 

Pets and even humans are susceptible to these parasites, according to the CDC. 

Dr. Jean Eye, chair of the veterinary technology department at Dallas College, said there is a low risk that pets in Dallas-Fort Worth are exposed to New World screwworm, especially as the USDA and state authorities work to contain the outbreak. 

Still, she said pet owners, especially those planning to travel with their pets to areas where cases have been reported, should be aware of how to prevent, identify and treat New World screwworm in pets. 

Eye said the wound does not need to be large for a New World screwworm to lay its eggs; even unnoticed tick bites and small scratches under a dog’s fur pose a risk. 

These larvae can do a “great deal of damage” to an animal’s tissue, Eye said. 

Eye says the disease is easy to spot in pets. Impacted wounds will grow large and emit a foul smell. Animals will also become irritated and frequently lick or rub the wound, she added. Maggots may also be visible surrounding wounds, according to the CDC. 

To prevent damage to pets, Eye said “the best prevention method is being vigilant.” She recommends petting down animals a couple times a week, especially checking inside a pet’s ears for larvae. 

Eye added that if you see a wound impacted by New World screwworm on your pet, it is essential to act quickly and take them to a veterinarian; there are no at-home methods to treat the parasite, and it is imperative the case is reported by the veterinarian to health authorities. 

The USDA is encouraging residents in the impacted areas of Texas and New Mexico to check livestock and pets daily for enlarged wounds, maggots, egg masses, signs of discomfort or irritability and lesions around body openings. Screwworm has been reported in cows and goats in Edwards, Gillespie, La Salle and Zavala counties in Texas.

This ease of identification in pets is what makes New World screwworm treatable.

“The biggest risk for animals is an untreated wound,” Eye said. Untreated wounds can become seriously harmful and even deadly. Since people spend time with their pets frequently, it would be challenging not to notice, she said. 

Eye explained that treatment entails a combination of removing maggots and administering medication to kill off larvae buried in the tissue. 

If maggots fall out of wounds, they should be placed in a leak-proof container with rubbing alcohol to kill them and brought to a healthcare provider, the CDC says. Throwing maggots in the trash could result in the spread of New World screwworm.