WASHINGTON, D.C. (Michigan News Source) – The U.S. government ordered testing of the nation’s milk supply for bird flu. The move comes as officials hope to better monitor the spread of the virus in dairy cows.

Testing will start in six states, including Michigan. Raw or unpasteurized milk from dairy farms and processors nationwide must be tested on request starting Dec. 16, according to the U.S. Department of Agriculture.

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Officials said the move is aimed at containing and ultimately eliminating the virus. It was detected for the first time in dairy cows in March. Since then, more than 700 herds have been confirmed to be infected in 15 states.

The risk to people from bird flu remains low, and health officials said pasteurization kills the virus in milk.

At least 58 people in the U.S. have been infected with bird flu. Most were farm workers who experienced mild symptoms after coming into contact with infected cows, milk, or poultry.