06/18/2026
UPDATE (6/8/2026 3:12pm): One of the NWS cases reported on the morning of June 8 has been reclassified as the first confirmed case in New Mexico. According to APHIS, "While the veterinarian who reported the case is located in Texas, the dog resides at a household in Lea County, New Mexico. Therefore, the location of the case will be reclassified to be the first case detected in New Mexico."
Details continue to emerge, and this post may become outdated.
On June 3, 2026, the U.S. Department of Agriculture's Animal and Plant Health Inspection Service (USDA APHIS) confirmed the presence of New World Screwworm (NWS) in Zavala County, Texas, approximately 50 miles north of the Mexico border. As of June 8, 2026, APHIS has confirmed a total of four cases of NWS, all located in southern Texas.
The New World screwworm fly (Cochliomyia hominivorax) is a parasite whose larvae can cause significant harm to warm-blooded animals. The female fly lays eggs in open wounds, body openings, and mucous membranes. Once the eggs hatch, the larvae burrow into the skin, consuming and tearing flesh with their sharp mouth hooks.
NWS flies are identifiable by their metallic blue or green body, orange eyes, and three dark stripes on their backs. Stay alert for maggots or white egg masses in wounds, body openings, or mucous membranes, as well as enlarging wounds, signs of pain or discomfort, and foul odors in warm-blooded animals. Currently, NWS has not been detected outside of southern Texas; however, it is crucial for residents across the larger southern United States to remain vigilant in order to protect wildlife, humans, pets, and livestock.
NWS is a reportable disease. If you observe any suspicious wounds or suspect a case of NWS, please contact a local accredited veterinarian or your state veterinarian.
You can monitor NWS presence, reports, and updates at screwworm.gov.
Read the full APHIS press release here: https://www.aphis.usda.gov/news/agency-announcements/usda-confirms-two-additional-cases-new-world-screwworm-united-states