By Emmy Powell
Communications Specialist

The U.S. Food and Drug Administration (FDA) issued an Emergency Use Authorization for a topical drug to help prevent New World screwworm (NWS) infestations in livestock and certain wildlife species.

CLiK Extra, a dicyclanil topical suspension, can be applied on or around wounds in sheep, cattle, goats, swine and camelids (e.g., camels, llamas, alpacas). The authorization also covers certain captive and captured wildlife: cervids, American bison, bighorn sheep and Sonoran pronghorn.

“Under President Trump’s leadership, we are giving American farmers, ranchers, veterinarians and wildlife managers the tools they need to fight back,” said Acting FDA Commissioner Kyle Diamantas, J.D. “Emergency use authorization provides a new tool for preventing the spread of New World screwworm infestations, and we will continue to work to combat this threatening pest.”

Unlike products that kill NWS larvae, CLiK Extra acts as an insect growth regulator. It disrupts larval development and stops the lifecycle before the larvae can cause tissue damage. The product is authorized only for prevention and should not be used to treat an existing NWS infestation.

“The FDA recognizes that the impact of New World screwworm extends beyond the farm gate,” Dr. Timothy Schell, director of FDA’s Center for Veterinary Medicine, said. “Authorizing this product for captive and captured wildlife species, including bighorn sheep, Sonoran pronghorn, American bison, and cervids like deer and elk, is about protecting these animals and helping ensure they do not contribute to the spread of NWS in the United States.”

This EUA authorizes CLiK Extra wound spray only for prevention of NWS myiasis associated with wounds, birth, and after surgical or husbandry procedures (e.g., dehorning, ear tagging, castration, tail docking, shearing). It is applied at the time of wound appearance or creation.

If a wound is already infested or if an infestation develops after administering the product, contact a veterinarian to discuss treatment options.

The wound spray is available over the counter.

The emergency use authorization will remain in effect until it is revoked or the federal emergency declaration for NWS is terminated.

Several other animal drugs have been conditionally approved or authorized by FDA for the prevention or treatment of NWS in livestock, horses, companion animals and other species.

For more information, read the CLiK Extra wound spray for New World screwworm fact sheet.