New World Screwworm Detected in Texas Threatens Livestock and Pets

The U.S. Department of Agriculture confirmed the first U.S. case of New World screwworm (Cochliomyia hominivorax) on June 3 in Texas, the first outbreak since 1982. The parasitic fly lays eggs in open wounds of warm‑blooded animals; larvae feed on living tissue and can cause rapid, severe damage.

Veterinarians warn pet owners and animal shelters to inspect wounds daily, keep injuries clean, and seek prompt veterinary care. Stray and unowned dogs and cats are at higher risk due to increased injuries and limited access to treatment.

The infestation poses a major risk to the state's dairy and beef industries. Experts estimate up to 38% of the U.S. dairy supply could be affected, potentially raising milk and beef prices by about 4% if even a small portion of the herd is impacted. Authorities may employ the sterile‑male release program—breeding infertile males to suppress the fly population—mirroring the successful strategy used to eradicate the pest in the 20th century.

No human cases have been reported, and the threat to consumer safety remains limited to the supply chain rather than direct food contamination.