Canada’s beef industry is not at risk from screwworms, but a spokesperson suggests that the recent reappearance of the flesh-eating parasite in the U.S. serves as a valuable reminder for Canadian farmers and ranchers to enhance their biosecurity measures. The Canadian Food Inspection Agency (CFIA) declared a temporary restriction on livestock imports from affected areas in the United States after New World screwworm was identified in a calf in Texas. The U.S. Department of Agriculture (USDA) confirmed additional cases in Texas and one case in a dog in New Mexico. While experts confirm that the screwworm cannot survive the Canadian winter, there is still concern about potential disruptions if an infected animal were to enter Canada.
Leigh Rosengren, the chief veterinary officer at the Canadian Cattle Association, commended the CFIA’s decision to ban Texas livestock imports, emphasizing the importance of safeguarding Canada’s export markets. The screwworm, historically prevalent in North and South America, resurfaced in the U.S. after decades, with the recent detection of an infestation in Texas. Although the parasite poses no direct food safety threat, it highlights the significance of maintaining national herd health.
Screwworm flies, known for their destructive larvae that feed on live tissue, have caused significant losses in the past. Canadian producers are advised to update their biosecurity protocols, especially for vulnerable animals like neonatal cows. The USDA is actively deploying sterile flies to combat the screwworm infestation and prevent its spread among wildlife. Efforts to ramp up sterile fly production are underway to control the parasite population effectively.
Despite minimal direct risk to Canadians, the presence of screwworms underscores the need for international collaboration to eradicate the parasite from the Americas entirely. This crisis presents an opportunity for Canada to engage with South American nations and work towards a comprehensive solution. Cooperation across borders is deemed essential for successful long-term management of the screwworm issue.