Only 3 Active Screw Worm Cases Remain in Northern Mexico

One case is 240 miles from Texas border, raising concerns for cattle industry

Published on Feb. 14, 2026

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Mexico's Agricultural Department reports that only three active cases of the New World screwworm remain in the northern state of Tamaulipas, down from 23 initially reported in December. The nearest case to the U.S.-Mexico border is 240 miles away, but the outbreak still threatens the cattle industry on both sides of the border. The U.S. has refused to accept live cattle imports from Mexico since last year due to the risk of screwworm infestation.

Why it matters

Screwworm outbreaks can devastate the beef and dairy industries if not contained, as the fly larvae burrows into open wounds and eats away at the flesh, ultimately killing the animal. Both the U.S. and Mexican governments have invested millions into eradication efforts, including a lab in southern Mexico producing sterile flies to neutralize the pest.

The details

The three remaining active cases are from the 23 initially reported in December in the state of Tamaulipas, which borders Texas. The Mexican government has been actively implementing a program to release sterile flies into the air to neutralize the pest, and so far no fertile flies have been found in 154 traps set up in Tamaulipas, compared to 28 fertile flies found in December 2025.

  • The 23 initial cases were reported in December 2025.
  • As of February 13, 2026, only 3 active cases remain.

The players

Mexico's Agricultural Department

The government agency reporting on the status of the screwworm outbreak in northern Mexico.

United States

Has refused to accept live cattle imports from Mexico since last year due to the risk of screwworm infestation.

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What’s next

The U.S. is building a multi-million dollar facility in Edinburg, Texas, near the border, to aid in the screwworm eradication efforts.

The takeaway

While the number of active screwworm cases in northern Mexico has declined significantly, the outbreak still poses a threat to the cattle industry on both sides of the U.S.-Mexico border, requiring continued vigilance and eradication efforts by both countries.