The Canadian Food Inspection Agency (CFIA) has released a comprehensive report on its monitoring of Canadian dairy cows for Highly Pathogenic Avian Influenza (HPAI) H5N1. As of June 18, 2024, CFIA laboratories tested 600 retail milk samples from various regions across Canada. The results were reassuring, with all samples testing negative for HPAI fragments and no evidence of the disease detected in dairy cattle milk.
HPAI, commonly known as bird flu or N5N1, has not been documented in Canadian cattle. This viral infection primarily affects birds, but there have been sporadic reports of the virus in other animals. However, these cases remain rare and typically result from direct contact with infected birds.
Commercially sold milk and milk products in Canada continue to be safe for consumption. Canadian regulations mandate that all milk must be pasteurized before sale. The pasteurization process is effective in killing harmful bacteria and viruses, including HPAI, thereby ensuring that milk and milk products are safe to drink and eat.
The CFIA’s testing focused on detecting viral fragments of HPAI in milk at the retail level. CFIA laboratories used a highly sensitive polymerase chain reaction (PCR) test, capable of identifying even non-infectious fragments of the virus. The negative results indicate the absence of HPAI fragments in the milk, supporting current reports that the virus has not been detected in Canadian dairy cows.
Additionally, CFIA laboratories and Health Canada recently concluded a study affirming that pasteurization effectively inactivates the HPAI virus in milk. This study aligns with international research published in the spring of 2024, confirming the efficacy of pasteurization in ensuring the safety of milk supplies.
The results from the Canada-wide testing are as follows:
- Atlantic Provinces: 151 samples tested, all negative
- Ontario: 149 samples tested, all negative
- Quebec: 150 samples tested, all negative
- Western Provinces: 150 samples tested, all negative
Health Canada led the study, conducted in May and June 2024, to evaluate the effectiveness of pasteurization in inactivating HPAI virus in milk. The pasteurization treatments tested were designed to simulate those used in the Canadian dairy industry and were found effective at inactivating high concentrations of the virus.
In Canada, HPAI is a reportable disease in all animals, meaning any suspected cases must be reported to the CFIA. Currently, there are no confirmed detections of HPAI in cattle in Canada.
Earlier in 2024, the USA experienced a breakout of H5N1 in dairy cattle, leading to heightened surveillance and stringent control measures to prevent the spread of the virus. This outbreak underscored the importance of vigilant monitoring and effective pasteurization processes to ensure public health safety.