Breaking down the escalating U.S. bird flu situation
CBC
California officials have declared a state of emergency over the spread of bird flu, where infections in dairy cows are increasing and causing sporadic illnesses in people in the U.S.
That raises new questions about the virus, which has spread for years in wild birds, commercial poultry and many mammal species.
The virus, also known as Type A H5N1, was detected for the first time in U.S. dairy cattle in March. Since then, bird flu has been confirmed in at least 866 herds in 16 states.
More than 60 people in eight states have been infected, with mostly mild illnesses, according to the U.S. Centers for Disease Control and Prevention (CDC). One person in Louisiana has been hospitalized with the first known severe illness caused by the virus, U.S. health officials said this week.
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Gov. Gavin Newsom said he declared the state of emergency to better position state staff and supplies to respond to the outbreak.
California has been looking for bird flu in large milk tanks during processing. And they have found the virus it at least 650 herds, representing about three-quarters of all affected U.S. dairy herds.
The virus was recently detected in Southern California dairy farms after being found in the state's Central Valley since August.
"This proclamation is a targeted action to ensure government agencies have the resources and flexibility they need to respond quickly to this outbreak," Newsom said in a statement.
Officials with the CDC stressed again this week that the virus poses low risk to the general public.
Importantly, there are no reports of person-to-person transmission and no signs that the virus has changed to spread more easily among humans.
In general, flu experts agreed with that assessment, saying it's too soon to tell what trajectory the outbreak could take.
"The entirely unsatisfactory answer is going to be: I don't think we know yet," said Richard Webby, an influenza expert at St. Jude Children's Research Hospital in Michigan.
But virus experts are wary because flu viruses are constantly mutating and small genetic changes could alter the outlook.