Canada is temporarily restricting imports of livestock, including horses, from Texas after last week’s confirmed finding of New World screwworm in a calf in the state.
The Canadian Food Inspection Agency said in a statement Friday that animals that originate from Texas, or were present there within 21 days before reaching the border, will not be accepted into Canada. The agency said the move is a precautionary measure aimed at preventing the parasite from entering the country and protecting animal health.
Several U.S. states have also taken steps to reduce the risk of the parasite spreading. The CFIA said it will continue working with U.S. officials to monitor developments and adjust its measures if needed.
New World screwworm is a parasitic fly whose larvae feed on the living tissue of warm-blooded animals. Infestations can cause serious and often deadly damage to livestock, pets, wildlife and, in rare cases, people. The parasite is endemic in parts of South America and the Caribbean, and Mexico has also reported cases.
The CFIA said Canada’s colder climate is not suitable for the long-term establishment of the fly, which prefers hot and humid conditions of about 25 to 30 degrees C. However, officials warned the flies can survive for shorter periods during the summer months, making temporary import controls an important safeguard.
Animal owners and veterinarians are being urged to watch for signs of infestation. A wound that worsens over time, especially one with discharge or a foul odour, may indicate the presence of screwworm.
New World screwworm is not found in Canada and is considered an immediately notifiable disease under the Health of Animals Act. Owners who suspect an infestation should contact a veterinarian, as confirmation requires laboratory testing. Laboratories must notify the CFIA of any suspected or confirmed cases.
Canada also does not allow the importation of cattle, bison, sheep, goats, cervids and swine from Mexico and stringent import conditions are in place for import of horses from Mexico to prevent introduction of animal disease.
