In light of the ongoing Highly Pathogenic Avian Influenza (HPAI) H5N1 outbreak affecting North American cattle, testing of all 95 licensed dairy farms across the state of Massachusetts has produced 100 percent negative results. To date, Massachusetts is the only state in the U.S. to test the entirety of its dairy herds for the virus.

Samples were collected in August 2024 by Massachusetts Department of Agricultural Resources (MDAR). The Massachusetts Department of Public Health (DPH) then worked with the Broad Institute at the Massachusetts Institute of Technology (MIT) and Harvard University to test the samples at no cost to farmers.

The testing was conducted in an effort to protect public health and demonstrate the safety of the dairy supply at Massachusetts farms. “Massachusetts dairy farmers follow stringent safety protocols,” said MDAR.

According to the U.S. Centers of Disease Control and Prevention (CDC), as of September 17, 2024, 207 dairy herds in 14 states have been affected by the HPAI H5N1 outbreak. Additionally, there have been four human cases of HPAI H5N1 infection attributed to dairy cow exposure reported in the U.S.

U.S. Food and Drug Administration (FDA) testing of milk at retail for the presence of HPAI H5N1 has shown no public health threat from the consumption of pasteurized products.

Moreover, the U.S. Department of Agriculture (USDA) recently announced that it is beginning field trials for a vaccine to address the virus, and that it will begin testing dairy cows at slaughter for the presence of HPAI H5N1.