Three more California dairy herds infected with H5N1 bird flu

California officials have identified three new outbreaks of H5N1 bird flu in Central Valley dairy herds, bringing the total number of infected farms to six.

Wednesday’s announcement comes as health officials in Missouri are trying to determine how a human who had no connection to dairy or poultry farming became infected. It is the 14th human case reported this year.

According to a statement from the U.S. Centers for Disease Control and Prevention, “while other novel flu cases have been detected through the country’s national flu surveillance system, this is the first time that system has detected a case of H5.”

The California Department of Food and Agriculture said the newly reported herds were in a “group targeted for testing due to elevated risks from their recent connections with the initial affected premises.”

Nationwide, 201 herds have been affected across 14 states. Another infected herd was identified in Michigan earlier this week.

A statement from the state agriculture agency said the finding of three additional herds was not unexpected, and was a testament to the agency’s surveillance methods, which are designed to find “affected farms as early as possible.”

Affected dairies have been quarantined and “enhanced biosecurity measures are in place to prevent the spread of the virus,” the agency said.

The risk of H5N1 remains low for the general population, and the state’s milk supply and dairy foods are safe and “not impacted by these events,” the statement said. Health officials say pasteurization inactivates the virus so there is no cause for concern for consumers of pasteurized milk or dairy products.

Steve Lyle, a spokesman for the state’s agriculture department, said none of the affected farms are raw milk farms.

There are at least four raw milk dairies in California. Three are located in the Central Valley, the fourth in Grenada, north of Mt. Shasta.

Mark McAfee, the owner of Raw Milk Farms — which operates farms in Fresno and Hanford — said he tests his milk regularly and so far, his herds are negative for the virus.