LOS ANGELES, Sept. 15 (Xinhua) -- The U.S. Department of Agriculture (USDA) on Monday confirmed the detection of highly pathogenic avian influenza (HPAI) in a dairy cattle herd in the state of Nebraska.

In a statement, the USDA said the confirmed strain is H5N1 clade 2.3.4.4b, genotype B3.13. The case was detected through state-led tracing and investigation following an initial finding from pre-movement surveillance milk samples, which are required under a federal order issued by the USDA in April 2024.

This marks the first known case of HPAI in cattle in Nebraska. Since the outbreak began in March 2024, dairy cattle infections have been reported in 17 states, though the USDA's Animal and Plant Health Inspection Service (APHIS) noted that cases have remained confined to a small number of states this year.

APHIS said it is working closely with the Nebraska Department of Agriculture to conduct additional on-farm investigation, testing and gathering of additional epidemiological information to better understand this detection and prevent further spread of the disease. The agency also urged all dairy farms to strengthen biosecurity measures, especially as the fall migratory bird season approaches.

There is no concern that this circumstance poses a risk to consumer health or that it affects the safety of the commercial milk supply, said the USDA.

The U.S. Food and Drug Administration (FDA) has confirmed that pasteurization is effective at inactivating H5N1, ensuring the safety of pasteurized milk products.

The U.S. Centers for Disease Control and Prevention (CDC) said that H5N1 viruses circulating in birds and U.S. dairy cattle are believed to pose a low risk to the general public in the United States, but warned that individuals with occupational or recreational exposure to infected birds or mammals are at higher risk and should take appropriate precautions. ■