Screwworm Fly Infestation Prevention Guidance Issued in Yucatán, Mexico

Veterinary specialist Abdiel Martín Park, commissioned by the Mexican government's Secihti program and the Universidad Autónoma de Yucatán, warned that open wounds on animals can become sites for the screwworm fly (Cochliomyia hominivorax) to lay eggs. He emphasized that periodic inspection of livestock and immediate treatment of any wound are essential to reduce infestation risk.

Key warning signs include non‑healing wounds, increasing size, bleeding, foul odor, discharge, inflammation, pain and, in some cases, visible larvae. The fly primarily infests cattle but can also affect sheep, goats, pigs, horses, dogs, cats, wildlife and, rarely, humans. Infestation is not transmitted by direct animal contact; each case results from a female fly depositing eggs on a wound.

Affected owners are advised to seek veterinary care promptly, notify zoosanitary authorities, keep wounds clean and protected, and follow professional guidance. The outreach forms part of Secihti Yucatán’s scientific dissemination effort, targeting producers in the Mérida region and surrounding areas.