What the new "flesh-eating fly" headlines actually mean for us — our dogs, our yards, and the greenbelt out back.
The New World Screwworm is a fly whose maggots feed on the living flesh of warm-blooded animals — livestock, wildlife, pets, and very rarely people. The U.S. wiped it out in 1966. For 60 years a "fly wall" of sterile insects in Panama kept it south. In 2026 it slipped through, worked north through Mexico, and reached Texas.
The single biggest source of confusion online is distance. Headlines say "Texas" and people picture it next door. Here's the real geography.
For the official, always-current zone boundaries, see the Texas Animal Health Commission zone map ↗ — the authoritative source, updated as zones change.
Zero cases anywhere near Austin. The fly needs an open wound to lay eggs, and your vaccinated, vetted, indoor-sleeping dog is a hard target. Go about your life.
The single best thing you can do costs nothing: glance over your dog for cuts, scrapes, or "hot spots" after greenbelt walks, and keep them on year-round flea/tick prevention (more below).
If cases appear in the Hill Country, Bexar (San Antonio), or Travis County, that's the signal to tighten up. This page tracks the official map so you'll know.
The same chewable flea-and-tick meds millions of dogs already take also kill screwworm larvae. In February 2026 the FDA cleared NexGard specifically to treat screwworm in dogs and cats, backed by real field studies. If your dog is on one of these, you've already got a strong layer of defense.
Ask your vet, but these are the chewables that do the job:
Don't double up or switch on your own — these are real medications, and a small number of dogs react to them. Let your vet steer.
Screwworm flies target any break in the skin — even a tiny scratch or a healing surgery/spay site.
A clean, covered wound is a wound a fly can't use.
Adult screwworm flies don't hang on animals; they rest in shaded, brushy, wooded areas — exactly what a greenbelt is. And the greenbelt is full of the deer, raccoons, and other wildlife that are the fly's natural hosts. None of this is happening near Austin yet, but if you've got woods out back, these are the smart habits.
Make the wound-check a routine the moment you come in off the trail — burrs, foxtails, and barbed brush cause the small cuts flies look for. Wipe down, look over, dress anything new.
Wildlife is the early-warning system. Report any wild animal with a foul-smelling open wound, visible maggots, or acting sick/lethargic. In the 1960s outbreak, screwworm killed an estimated 80% of Texas white-tailed deer — biologists are watching closely.
Don't approach wildlife — note it and call (see below).
Keep the strip where your yard meets the belt trimmed and clear of carcasses or rotting debris that draw flies. Bring dogs in at dusk when flies are active. Simple, low-effort, good practice regardless.
The tell-tale sign across every species is the same: an open wound that gets worse instead of better, smells like rotting flesh, and may have visible maggots burrowing in (not crawling on top).
Texas law asks for suspected cases to be reported within 24 hours. Save these numbers in your phone now.
We read a lot of online chatter so you don't have to. The facts that keep getting mangled:
"The flies are already in Austin / they fly hundreds of miles."
Adult females typically travel a few miles searching for a host. Long-distance spread happens when infested animals move — which is exactly why the zone has a movement quarantine.
"It's in the meat — I'm not eating beef."
Screwworm infests living tissue, not meat, produce, or food on shelves. The food supply is safe. (Beef prices may rise from herd disruption — that's an economics story, not a safety one.)
"It spreads person-to-person like COVID."
It's not contagious between people. A fly lays eggs in a wound; that's the whole transmission route. Human cases are rare and there are none locally acquired in the U.S.
"Nothing can stop it now."
Releasing millions of sterilized flies wiped screwworm out of the U.S. before — across the country in 1966, and again in the Florida Keys in 2017. It's slow, but it works.
Skip the rumor mill. These are the primary sources this page is built from — check them directly any time.