Archive · 25 Aug 2026
US Border Reopens to Mexican Cattle Amid Screwworm Concerns
The United States has started allowing cattle from Mexico to enter again.
The first reopened crossing is in Douglas, Arizona.
More crossings in New Mexico may reopen later.
Officials are worried about screwworm, a pest that can harm animals by feeding on their flesh.
Mexico says it is checking animals and controlling where livestock can move.
It is also releasing sterile flies that cannot produce babies with wild flies.
Some American cattle groups and officials think reopening the border could spread the pest.
The United States says the plan has safeguards and can be paused if the risk increases.
The United States reopened the Douglas, Arizona, port to Mexican cattle under a phased plan.
Ports in Santa Teresa and Columbus, New Mexico, could reopen after further evaluation.
Mexico reported 183 screwworm cases in Chihuahua and two in Sonora.
U.S. cattle groups and state officials warned that renewed imports could increase risks.
Mexico plans to expand sterile-fly releases, while the United States is building a Texas production facility.
- Who
- The United States Department of Agriculture, Mexican agricultural authorities, cattle producers, and state officials are involved.
- What
- The United States has begun a phased reopening of its border to Mexican cattle imports while Mexico strengthens screwworm controls.
- When
- The reopening began Monday, August 24.
- Where
- The first reopened port is in Douglas, Arizona; additional ports in New Mexico are under evaluation, while cases have been reported in northern Mexico.
- Why
- The border is reopening under agreed safeguards and a science-based protocol, while authorities seek to protect livestock from screwworm.
Reopening Supporters
Reopening Critics
Border trade
Reopening Supporters
U.S. and Mexican authorities support a phased reopening based on overlapping safeguards and a science-based import protocol.
Reopening Critics
Some U.S. cattle groups and state officials oppose or criticize renewed imports because they could increase screwworm risks.
Disease-control strategy
Reopening Supporters
Mexican authorities say sterile-fly releases, inspections, movement controls, and treatment campaigns can contain the pest and support reopening.
Reopening Critics
Critics point to the parasite's continued spread in northern Mexico and reported detections in Texas and New Mexico as reasons for caution.
Ability to respond
Reopening Supporters
The United States Department of Agriculture says ports can be paused if audits or other information show increased risk in Sonora or Chihuahua.
Reopening Critics
The presence of cases in key cattle-exporting regions means critics remain concerned that safeguards may not prevent further spread.
- First reopened port
- Douglas, Arizona
- Ports under evaluation
- Santa Teresa and Columbus, New Mexico
- Reported Chihuahua cases
- 183 confirmed cases since the first detection in July
- Reported Sonora cases
- Two confirmed cases
- Key control method
- Releasing sterile flies that produce no offspring when mating with wild females
- Mexico's measures
- Surveillance, inspections, livestock movement controls, treatment campaigns, and sterile-fly releases
- U.S. facility
- A sterile-fly production facility is being built in Texas and is expected to be completed by spring 2027