The Canadian Food Inspection Agency (CFIA) has toughened import requirements on U.S. breeding cattle over the H5N1 bird flu virus. Import measures for cattle from the U.S. will now include negative Highly Pathogenic Avian Influenza (HPAI) test results for lactating dairy cattle and testing of milk at the retail level to look for viral fragments of the virus. Katherine Ward has this story and more in Health Matters for May 6, 2024.