06/11/2026
❗️❗️New World Screwworm❗️❗️
As many of our pet parents may know, since the beginning of June 2026, cases of New World Screwworm have been detected in southwest Texas and New Mexico. These are the first cases of NWS in the United States in 60 years. The United States Department of Agriculture (USDA) and state departments of agriculture and health officials are working together to address the issue.
The American Kennel Club (AKC) recommends that all dog owners, or anyone who works with dogs, learn about NWS and stay updated on developments and should become familiar with new health requirements imposed to help prevent further spread of the pest.
About New World Screwworm
NWS is a parasitic fly whose larvae burrow into the living tissue of warm-blooded animals, typically through an open wound, causing painful wounds, serious infection, and sometimes death. It can affect livestock, wildlife, pets, and occasionally dogs, which may be at risk if they have open wounds or if they come into contact with infested animals or contaminated areas. People are also susceptible to NWS larvae.
Despite being eradicated from the U.S. in 1966, NWS remained prevalent in countries throughout the western hemisphere. Following an increase in the number of cases identified in Central America in 2023, NWS was identified in southern Mexico in 2024. When models predicted NWS would enter the U.S. in 2025, USDA invested heavily in tools to address NWS, including expediting the targeted and aerial release of sterile screwworm flies, increased trapping for screwworm files along the southern U.S. border and just outside of the area where sterile flies have been released, implementing NWS surveillance and management strategies in wildlife, and conducting outreach in local areas. Similar strategies were successfully used to eradicate screwworm from the U.S. in 1966 and to eliminate a small outbreak of screwworm in the Florida Keys in 2017. USDA also ensured that the National Veterinary Stockpile was supplied with treatments, equipment, and logistics to support the nation’s response to NWS.
⚠️⚠️⚠️Steps Dog Owners Can Take to Prevent New World Screwworm Infestation⚠️⚠️⚠️
According to USDA, dog owners should take the following steps to help prevent the spread of NWS:
Watch for signs of NWS, including irritated behavior, head shaking, smell of decay, and presence of fly larvae (maggots) in wounds. Seek immediate veterinary intervention if you suspect your dog is experiencing an NWS infestation.
Protect dogs from other wound-causing parasites like ticks. Oral and topical flea and tick preventatives containing afoxolaner, lotilaner, or sarolaner actively prevent and treat NWS larval infestations in pets.
Make sure pets traveling internationally are inspected for screwworm.
In addition to state-level general interstate dog movement regulations, comply with federal and state animal movement restrictions created to prevent the spread of screwworm (above).