Update: July 2, 2026 - NWS Resource for Employers with Farm, Livestock, and Outdoor Workers
The National Center for Farmworker Health (NCFH) hosted a webinar on June 25, 2026, about the public health implications of New World Screwworm (NWS) for farm, livestock, and outdoor workers with emphasis on regions with active cases of NWS.
You can keep up to date with NWS detections via the USDA APHIS NWS Dashboard.
While human infections of NWS in California and the United States are rare, they can happen if wounds are not properly attended to and there are localized detections of NWS. In Central America and Mexico, NWS infections account for 2,193 cases out of ~187,000 cases or approximately ~1% of cases (CDC 2026).
NCFH has created English and Spanish fact sheets for recognizing potential infections in animals and people for dissemination. The most obvious symptoms of a possible infection are movement of larvae (both visible and invisible) in a wound and/or a bad odor from a wound that might be having difficulty healing. Refer to the fact sheet for more details.
Update: June 12, 2026 - CA Animal Quarantine
The California State Veterinarian has declared an Animal Quarantine for any animals entering California from states' affected by New World Screwworm (NSW) - effective June 12, 2026, at 9AM. Earlier this month, NWS was identified in a calf in Texas by the USDA Animal and Plant Health Inspection Service (APHIS).
This animal quarantine applies to:
- all livestock - cattle, swine, sheep, goats, and camelids;
- equine - horses, mules, and donkeys;
- domesticated poultry - chickens, turkeys, waterfowl, peacocks, guinea fowl, pigeons, upland gamebirds, and ratites;
- captive cervids - deer, elk, moose, and reindeer, and
- companion animals (dogs, cats, pet psittacines/parrots, rabbits, and domestic rodents.
Visit the California Department of Food and Agriculture (CDFA) for up to date information about NWS and to sign-up for live texts.
To learn more about NWS - read this factsheet provided by CDFA.
USDA APHIS has also compiled a photo gallery of NWS in various stages as well as animal infestation and treatment for educational purposes. The below image is an example. Please be aware some of these images are graphic.
June 5, 2026 - Announcement of New World Screwworm in United States
New World Screwworm (NWS) is detected in Texas. See post on the Livestock and Range blog from Dr. Fadzayi E Mashiri, UCCE Livestock and Natural Resources Advisor for San Benito, Santa Cruz, and Monterey Counties.