New World Screwworm Preparedness

The New World screwworm (Cochliomyia hominivorax) is a parasitic fly whose larvae feed on the living tissue of warm-blooded animals. Eradicated from the United States decades ago, it is now moving north again, and early detection is the single most important factor in containing an outbreak. The Hubbard Lab leads screwworm preparedness efforts across New Mexico and the Southwest, working with livestock producers, veterinarians, county Extension agents, wildlife managers, and animal health officials to make sure suspect cases are recognized quickly and reported through the right channels.

What we offer

Hands-on trainings and workshops that teach participants to recognize suspect infestations, conduct efficient animal inspections, and collect and submit larvae and flies for identification. Webinars on surveillance tools, trapping, reporting, and response workflows for producers and agency staff. Identification support for suspect flies and larvae, including help distinguishing New World screwworm from commonly confused blow flies. Stakeholder needs assessments so that materials, protocols, and surveillance designs are practical, locally relevant, and easy to implement in the field.

Resources

Adult New World Screwworm Identification and Commonly Confused Species (NMSU Extension Guide A-156, 2026): https://pubs.nmsu.edu/_a/A156/index.html

New World Screwworm: What You Need To Know (NMSU Extension Guide B-115, 2025): https://pubs.nmsu.edu/_b/B115/

MeatEater Podcast, Ep. 835: Attack of the Screw Worms (February 2026), featuring Dr. Hubbard: https://www.themeateater.com/listen/meateater/ep-835-attack-of-the-screw-worms

If you suspect screwworm

Do not wait. Contact your veterinarian and the New Mexico Livestock Board or your state animal health official immediately, and do not move the animal. If possible, collect larvae from the wound into rubbing alcohol and photograph the wound. Our lab can help with identification; email calebh@nmsu.edu with photos and your location.

Request a training

Interested in hosting a screwworm or urban pest workshop for your county, ranch, veterinary practice, or organization? Email Dr. Caleb Hubbard at calebh@nmsu.edu with your location, audience, and preferred dates.