New World screwworm has never had a good treatment story. The larvae eat living tissue, and a vet’s options were mostly grim: pull them out, clean the wound, manage the damage. On November 3 the FDA added a real tool, granting an emergency use authorization to Bravecto (fluralaner) chewable tablets for screwworm infestations in dogs and puppies.
Bravecto already has approval for fleas and ticks, so the ingredient is familiar to most owners. The authorization lets vets prescribe it for myiasis, the clinical name for a maggot infestation, after weighing the dog in front of them. It is not an over-the-counter fix. Fluralaner belongs to the isoxazoline class, which can cause muscle tremors, loss of coordination, or seizures in a small number of dogs. That risk is why the FDA kept the drug prescription only. If your dog has a seizure history, that conversation with your vet matters more than usual.
Risk is still geographic. The FDA says most US dogs are at low risk because confirmed cases sit in a limited region. Infested zones as of November 3 run through Cochise County in Arizona, eight New Mexico counties, and a long stretch of west and south Texas from El Paso to Zapata. Dogs that live in those counties, travel through them, or arrive from countries south of the border are the ones to watch.
What this means for your dog: check wounds daily if you are in or near an infested zone, and keep flea and tick prevention current. Maggots in a cut, a smell of decay, or a dog fussing at an ear means a same-day vet call. The warning signs are laid out in this earlier post on screwworm reaching Texas wildlife. What is new is that your vet finally has a prescription to reach for.