FDA Authorizes Emergency Treatment for New World Screwworm Infestations Amid Arizona Cases
The U.S. Food and Drug Administration has authorized emergency use of a treatment for New World screwworm infestations in dogs and puppies. This comes as Arizona has confirmed five cases of the parasitic fly's larvae in animals, including horses, dogs,…
Tucson, AZ, November 10, 2026 — The U.S. Food and Drug Administration (FDA) has granted emergency use authorization for a treatment aimed at combating New World screwworm infestations in dogs and puppies. This development follows recent confirmations of the parasitic fly’s larvae in animals within Arizona.
Arizona has reported a total of five cases of New World screwworm infestations. The affected animals include horses, dogs, and a sheep. The majority of these confirmed cases are located in the eastern and southeastern regions of the state.
The New World screwworm (Cochliomyia hominivorax) is a species of New World fly that is known to lay its eggs in the open wounds of warm-blooded animals. Upon hatching, the larvae burrow into the living flesh of the host animal, feeding on it and causing severe tissue damage, pain, and potentially death if left untreated. The infestation poses a significant threat to animal health and can impact livestock and companion animals.
The emergency use authorization by the FDA signifies a critical step in addressing the current and potential future outbreaks. While the summary indicates the authorization is for dogs and puppies, further details regarding the specific treatment and its broader applicability were not provided.
The precise timeline for when these Arizona cases were identified was not specified in the provided information. Similarly, details about the origins of the infestations, the specific veterinary or public health agencies leading the response on the ground beyond the FDA’s authorization, or any preventative measures being implemented in affected areas were not detailed. The contractor responsible for any related services or the outcome of any specific interventions were also not mentioned.
New World screwworm infestations were historically eradicated from the United States in the mid-20th century through large-scale control programs. Their re-emergence in recent years has raised concerns among animal health officials and veterinarians, prompting vigilance and the need for effective control measures and treatments. Further updates on the spread and management of these infestations are anticipated.
Story summarized from the original created by Karina Bazarte on www.kold.com, see more information here.
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