The U.S. Food and Drug Administration has issued an Emergency Use Authorization for Ivermectin Liquid for Horses to provide short-term prevention of New World screwworm infestations in horses, according to a news release from FDA.

The authorization is part of the Trump administration’s efforts to protect American agriculture from the threat of New World screwworm. The product, ivermectin oral solution, is authorized for use when administered within 24 hours of birth or at the time of initial wound care. It is not approved for use in species other than horses.

“The Trump administration will use every available tool to stop New World screwworm from threatening America’s horses and livestock,” said U.S. Health and Human Services Secretary Robert F. Kennedy, Jr. in the release. “This EUA expands our defenses, strengthens our preparedness, and helps protect the animals, producers, and communities that drive American agriculture."

The release said the FDA determined, based on the totality of available scientific evidence, that it is reasonable to believe Ivermectin Liquid for Horses may be effective in the short-term prevention of New World screwworm myiasis in horses when used as authorized. The FDA also concluded the known and potential benefits of the product outweigh its known and potential risks.

"President Trump has directed his entire administration to do what it can to combat and stop the spread of New World screwworm. We at USDA have been working with our federal partners to prepare for any potential infestation of animals that may occur as a result of New World screwworm, and today’s announcement is another step in the right direction," said U.S. Department of Agriculture Secretary Brooke L. Rollins. "HHS and FDA have stepped up to the plate and have moved at Trump speed to authorize as many treatments as needed to protect our livestock, wildlife, and companion animals. I am thankful to Secretary Kennedy for getting this authorization across the finish line and ensuring our horse population has access to preventative measures, should they need it.”

New World screwworm is a parasitic fly whose larvae feed on the living tissue of warm-blooded animals. According to FDA, newborn animals with healing umbilical wounds and animals with open wounds are especially vulnerable because the flies are attracted to those areas to lay their eggs. Untreated infestations can become severe and life-threatening.

“This authorization provides a short-term prevention option for horses, but owners and veterinarians should be aware of the limitations,” said Timothy Schell, Ph.D., director of the FDA’s Center for Veterinary Medicine. “This product's window of prevention lasts no more than 24 hours, so it is important that the product be used alongside other preventive measures such as bandaging, repellents, and other fly-control methods."

FDA said in the release that the Emergency Use Authorization only covers short-term prevention of New World screwworm myiasis and does not authorize treatment of existing infestations. If a wound is already infested or an infestation develops after administering Ivermectin Liquid for Horses, owners should contact a veterinarian to discuss treatment options.

“The Trump administration is leaving no stone unturned in our fight to shield American ranchers, livestock producers, and the agricultural economy from this threat,” said Acting FDA Commissioner Kyle A. Diamantas, J.D. “This marks the FDA’s 11th Emergency Use Authorization deployed against New World screwworm, and we will continue to use all available authorities, act with maximum speed, and deliver tools to protect animals in the U.S.”

The FDA said in the release that Ivermectin Liquid for Horses is a clear, ready-to-use solution that can be administered as an oral drench or through a tube placed from a horse’s nose to its stomach. The product is available only by prescription from a licensed veterinarian.

The FDA emphasized that the product should not be used in species other than horses. The authorization is intended as a temporary prevention measure and should be used with other methods, including wound care, bandaging, repellents and fly-control measures.

Detailed product information is available in the Fact Sheet: Emergency Use Authorization of Ivermectin Liquid for Horses (ivermectin oral solution) for New World Screwworm (NWS), according to the news release from FDA.

The Emergency Use Authorization will remain effective until it is revoked or until the HHS secretary terminates the declaration that the potential public health emergency presented by New World screwworm justifies emergency use authorization of animal drugs for the disease.

Ivermectin Liquid for Horses is sponsored by Alberta Vet Labs Ltd., which is based in Canada.