The Idaho State Department of Agriculture has rolled out stricter requirements for animals entering the state following the first confirmed detection of New World screwworm in the United States since its eradication nearly four decades ago. The pest was confirmed in Texas and New Mexico on June 3, prompting state officials to act quickly to protect Idaho’s livestock industry — the backbone of the Treasure Valley economy and much of rural Canyon County.
What the New Rules Require
Under the updated entry requirements issued this week, any warm-blooded animal entering Idaho from a screwworm-infested state must be accompanied by a Certificate of Veterinary Inspection issued no more than five days before the animal’s arrival. Animals coming from areas formally designated as screwworm-infested zones must also carry a movement permit from the state of origin.
As of Wednesday, the U.S. Department of Agriculture had designated infested zones in southern Texas only. Idaho officials are watching the situation closely, as additional areas — including parts of New Mexico — could receive formal designations as the federal response continues to develop.
State officials are also urging Idaho residents to think twice before traveling with pets to affected states. Any pet returning to Idaho from a screwworm-affected area must have a health certificate from a licensed veterinarian in that state, issued within five days of the animal’s return.
Idaho State Veterinarian Scott Leibsle noted that the risk to companion animals is real and often overlooked. “Dogs and cats are just as susceptible to the pest as livestock, but pet owners may be less aware of the importance of thoroughly inspecting their pets for fly larvae,” he said.
Why This Matters for Idaho Agriculture
The screwworm threat carries particular weight in Idaho, where cattle and dairy production rank as the two largest agricultural sectors. Canyon County is home to a significant share of the state’s dairy operations, making any parasitic outbreak with the potential to spread through livestock a serious economic concern for local farming families.
New World screwworm larvae burrow into the living tissue of warm-blooded animals, causing severe and potentially fatal wounds. The USDA launched eradication efforts in the 1950s, and the pest was fully eliminated from the United States by 1986. A limited recurrence emerged in Florida in 2016 but was contained and eliminated by early 2017.
Idaho Agriculture Director Chanel Tewalt indicated the state was not caught off guard. “Idaho has been preparing for the possibility of New World screwworm reaching the United States, and we are well-positioned to respond,” she said.
What Comes Next
Idaho agriculture officials will continue monitoring USDA designations of infested zones as federal authorities respond to confirmed cases in Texas and New Mexico. The current entry requirements apply specifically to animals arriving from those designated areas, but ranchers and livestock producers across Canyon County and the broader Treasure Valley should expect requirements to expand if the pest spreads to additional states.
Livestock owners and pet owners planning travel to affected regions are encouraged to contact a licensed veterinarian before moving animals across state lines. Canyon County producers can reach the Idaho State Department of Agriculture for the most current guidance on movement permits and certification requirements.
For broader coverage of the screwworm situation and its implications for Idaho agriculture, visit Idaho News.