CHICAGO, Sept 15 (Reuters) - Nebraska confirmed its first case of bird flu in a dairy cattle herd, the U.S. Department of Agriculture said on Monday, showing the virus continues to spread in livestock after an outbreak began last year.

Dairy cattle in 17 states have been confirmed to be infected since the start of the outbreak in March 2024, though reports of cases generally have slowed since last year, according to the USDA. California, Michigan, Nevada, Idaho, Arizona and Texas also reported cases in herds this year.

Infected cows often produce less milk, consume less feed and suffer other symptoms.

Bird flu viruses circulating in dairy cows and birds pose a low risk to the general public, according to the U.S. Centers for Disease Control and Prevention. Farm workers who come in contact with infected animals are more at risk.

Since 2024, the virus has infected 70 people, mostly workers on dairy farms, according to the CDC.

Pasteurized milk sold to consumers is safe because pasteurization has been shown to inactivate the virus, the USDA said in a statement.

The herd in Nebraska is located in the central part of the state and has been quarantined, according to the Nebraska Department of Agriculture.

The strain of the virus is similar to a strain from California, the top U.S. milk-producing state, which had a major outbreak last year and found more cases in 2025, the department said.

Nebraska is a major producer of cattle raised for beef, though bird flu has not been confirmed in U.S. beef cattle.

Reporting by Tom Polansek; Editing by Sonali Paul

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Tom Polansek

Thomson Reuters

Tom has been a journalist for Reuters in Chicago since 2011. He writes primarily about food and agriculture, and has reported on disruptions to global fertilizer and grain supplies from Russia's invasion of Ukraine. He also covers U.S. livestock production and meatpacking companies including Tyson Foods, Smithfield Foods and JBS. Tom was part of a team of reporters that Reuters named as Journalists of the Year in 2016 for coverage of Monsanto. He also won awards from the North American Agricultural Journalists.

Nebraska confirms first case of bird flu in dairy cattle herd