The following is an open letter from Oklahoma State Veterinarian Dr. Rod Hall as he updates stakeholder on the New World Screwworm situation:
“I wanted to give a New World Screwworm update, now that we’re on our way into summer and fly larvae will be a common occurrence.
“Mexico, USDA, and Texas continue to take actions to prevent incursion of NWS into the United States. Mexico is reporting cases almost daily within 100 miles of the Texas border.
“100 million sterile flies continue to be produced in Panama. They are all being released in northern Mexico in the States of Tamaulipas, Nuevo Leon, and Coahuila, and about 25 miles into Texas from around Del Rio to Matamoros. USDA and Texas are setting out fly traps along the border to hopefully find fertile NWS flies if they do make it into Texas. There is a map above that shows the area of fly releases.
“Later this summer, Mexico will have a plant online producing an additional 100 million sterile flies. Our hope is that the partners can keep the flies south of the border until fly reinforcements are available.
“The message I want you to remember is:
- There are no confirmed cases of NWS in the USA currently.
- NWS does not affect food for human consumption.
- Don’t panic or frighten the public unintentionally.
- Be aware and report suspicious cases BEFORE sending samples to the lab.
- It’s very common to see fly larvae (maggots) during fly season. Just because there are maggots does not mean they are NWS maggots.
- NWS flies only lay eggs on living, warm blooded animals. The eggs tend to be laid in “shingle like” patterns. The maggots tend to burrow deep into the living tissue with their rear ends pointing toward the outside of the wound. NWS myiasis has a very distinct foul smell and wounds commonly have drainage.
“To report suspicious cases, please call our office at 405-522-6141.”
Learn more about the efforts at the federal government level- click here for Screwworm.Gov.
Note: The May 18th cases of screwworm reported by the Mexican government include a sixteen month old feline 57 years from the US border- discovered on May 16, 2026..
