⚠ Active outbreak: [VERIFY:32] confirmed U.S. cases in Texas & New Mexico. See the latest →

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For producers

Screwworm in cattle and livestock

For a cattle operation, screwworm is a working threat, not a curiosity. Any animal with an open wound is a target, and newborn calves — with a fresh navel — are especially vulnerable.

Signs to look for

  • A wound that grows instead of heals.
  • Draining or foul-smelling discharge.
  • Visible maggots deep in the wound.
  • Animals that are restless, off feed, isolating, or headshaking (if the infestation is in the head or nose).

Check high-risk sites first: navels of newborns, castration and branding wounds, tick bites, dehorning sites, and any cut or sore.

What to do if you suspect it

Do not wait. Report immediately to your state animal health authority — in Texas, your TAHC area office or your USDA area veterinarian in charge. Isolate the animal if practical.

Full reporting steps and contacts are on Take Action.

Prevention

  • Inspect stock regularly — especially after any procedure that breaks skin.
  • Time husbandry procedures to lower-risk windows where possible.
  • Treat and cover wounds.
  • Watch newborns closely, particularly the navel.
[VERIFY] Confirm current USDA / TAHC prevention guidance before publish.

Why early detection matters for your herd

The earlier an area outbreak is caught and mapped, the faster sterile-fly coverage and quarantines can protect your operation. That's exactly what we're building.

Practical note: this page is informational, not a substitute for your veterinarian or state animal health official — loop them in early.


Related: New World Screwworm: the complete guide · Screwworm in pets & humans · Live outbreak status

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