The Canadian Food Inspection Agency (CFIA) has implemented temporary import restrictions on livestock, including horses, from entering Canada from areas in the U.S. that have been affected by New World screwworm (NWS).
Animals that originate from or were present in the state of Texas within 21 days prior to border crossing will not be accepted into Canada. Several U.S. states have also taken precautionary actions to mitigate the risk of spread. The CFIA will continue to work closely with U.S. counterparts to assess developments and adjust measures as needed.
The flesh-eating larvae of this parasitic fly threatens the lives of its host animals. While a colder climate is not hospitable for the long-term establishment of the fly in Canada, they can survive shorter periods of time in the summer months. Taking this action now is an appropriate risk mitigation measure to prevent its introduction and protect animal health.
Animals owners and veterinarians are encouraged to be on the lookout for signs of screwworm infestations in livestock. A wound that worsens over time and is accompanied by discharge or foul odor is also usually observed. For Canadians traveling to Texas with their companion pets, they are encouraged to remain vigilant and inspect their pets regularly for any signs.
In Canada, NWS is an immediately notifiable disease under the Health of Animals Act. Owners should contact their veterinarian if they suspect signs of NWS as identification of the fly can be confirmed only with laboratory testing. Laboratories are required to contact the CFIA regarding the suspicion or confirmation of infestation.
