Commercial milk sampling and testing for highly pathogenic avian influenza (HPAI) viral fragments in Canada

As part of the Government of Canada's One Health approach, the Canadian Food Inspection Agency (CFIA) in collaboration with the Public Health Agency of Canada (PHAC) and Health Canada is taking proactive measures to monitor Canadian dairy cows for HPAI.

Commercially sold milk and milk products remain safe to consume. In Canada, milk must be pasteurized before sale. The pasteurization process kills harmful bacteria and viruses, including HPAI, ensuring milk and milk products are safe to drink and eat.

We conducted testing of milk at the retail level to look for viral fragments of HPAI. CFIA laboratories tested commercial milk samples from across Canada using a type of polymerase chain reaction (PCR) test. The method used to test milk for HPAI is very sensitive and is able to detect fragments of the virus, even if the virus is not infectious.

Negative results mean that HPAI fragments are not present in milk. This supports current reports that the virus has not been detected in Canadian dairy cows.

In addition, CFIA laboratories and Health Canada recently completed a study, which provides additional reassurance that pasteurization is effective in inactivating HPAI virus in milk.

Milk sampling and testing results

As of June 18, 2024, CFIA laboratories tested 600 retail milk samples from across Canada. All samples have tested negative for HPAI fragments, with no evidence of disease in dairy cattle detected in milk.

Results of the Canada-wide testing of retail milk samples are listed below. Next steps on testing will be decided as part of further discussions with federal and provincial partners.

Area Samples tested HPAI detections (positive or negative)
Atlantic provinces 151 All negative
Ontario 149 All negative
Quebec 150 All negative
Western provinces 150 All negative

Milk pasteurization study

Under the leadership of Health Canada, CFIA laboratories carried out a study in May and June 2024 on the effectiveness of pasteurization to inactivate HPAI virus in milk. Consistent with similar studies published internationally, the results showed that pasteurization is effective.

The pasteurization treatments tested were chosen to simulate those used by the Canadian dairy industry, and showed that they were effective at inactivating high concentrations of the virus that were added to raw milk.

These findings align with similar results obtained in spring 2024 by other researchers globally and provide additional reassurance that the milk supply in Canada is safe, even if HPAI virus were to be detected in Canada.

How we are responding to HPAI in cattle

In Canada, HPAI is a reportable disease in all animals. All suspected cases must be reported to the CFIA. There are currently no confirmed detections of HPAI in cattle in Canada.

Learn more about protective measures in place for HPAI in livestock in Canada.