Background: In April of 2024, studies in the United States (US) identified the presence of influenza A(H5N1) viral RNA in 20%-40% of commercially available pasteurized milk in the US, suggesting that cattle infections were widespread across the country.

Methods: As an initial assessment of the situation in Ontario, 117 samples of pasteurized cow´s milk purchased from retail outlets in Ontario in April and May of 2024 were tested for the presence of influenza A viral RNA.

Results: No influenza A viral RNA was detected.

Conclusion: The Canadian Food Inspection Agency has subsequently developed an ongoing surveillance system for testing commercially available pasteurized milk and raw milk at processing plants in Canada.