Arizona Sets Pet Travel Rules as Screwworm Cases Reach Six

Arizona's Office of the State Veterinarian has issued travel guidance for dogs and cats as the state's confirmed New World screwworm case count reaches six. The November 9, 2026, memo, signed by assistant state veterinarian Sarah Heinrich, DVM, is addressed to veterinarians and clients, and it makes USDA-accredited veterinarians responsible for verifying destination states' entry requirements.

The six confirmed cases, per the Arizona Department of Agriculture dashboard as of November 13, are two in dogs, three in horses and one in a sheep. Officials set a mandatory infested zone of 20 kilometers, about 12.4 miles, around every confirmed detection. Arizona has three active zones. The state's first detection, a dog in Cochise County, was announced by the USDA's Animal and Plant Health Inspection Service on October 28, 2026.

Where a pet starts decides what it needs. Dogs and cats outside an infested zone face no movement restrictions inside Arizona, and Arizona sets no requirements of its own for them to leave the state. Their owners still have to meet the destination state's import rules, which is where the accredited veterinarian and the certificate of veterinary inspection come in.

Inside a zone, the rules tighten. A dog or cat moving within Arizona from an infested zone must be on an FDA-approved, conditionally approved or emergency-authorized treatment for screwworm. Leaving the state from a zone takes three things: an Arizona premovement permit, an electronic certificate of veterinary inspection, and whatever the destination state adds on top.

The memo tells owners with a trip planned to start with the destination state's current requirements, and it tells the accredited veterinarian to verify that information directly with the destination state's animal health official. The screwworm situation is moving, and the memo doesn't treat a website as the last word.

One case explains the caution. The fifth confirmed case was a domestic dog near Thatcher in Graham County with no known history of travel. A parasite that shows up in an animal that hasn't moved is harder to draw a clean map around, and that's the map Arizona is now asking pet owners to travel with.