California declared a state of emergency this week over the spread of bird flu in the state as the virus continues to be detected among the state's cattle herds.
California Gov. Gavin Newsom (D) said in a statement Wednesday that the declaration of an emergency is meant to "ensure government agencies have the resources and flexibility they need to respond quickly to this outbreak."
This action marks one of the most significant developments in what has been a year marked by the underlying presence of bird flu. Since March, the Centers for Disease Control and Prevention (CDC) has confirmed 61 human cases across eight states.
No human-to-human cases have been detected so far.
Here's what to know.
Among all states that have confirmed cases of bird flu, California has by far the highest number at 34 known infections. Washington state ranks second with a third of California's cases.
The vast majority of the Golden State's infections — 33 — have been linked to dairy herds. One case is considered to have come from an unknown source. Bird flu was first detected in a California dairy cow in August.
The strain that has infected California cattle and spread to humans comes from the B3.13 genotype, different from the strain detected in wild birds and poultry in the U.S. and Canada. This latter lineage is believed to be the cause of the first severe case of bird flu that hospitalized a Louisiana patient.
The strain among birds has been found in 51 jurisdictions, while only 15 other states have detected bird flu outbreaks among their cattle herds.
Newsom's office stated that the decision to declare a state of emergency was meant to "streamline and expedite" the state's bird flu response.
As Newsom stated in his announcement Wednesday, the risk of bird flu to the general public "remains low," an assessment that federal health authorities have stated throughout this year.
The CDC reiterated this when announcing the first severe case of bird flu this week, stating, "No person-to-person spread of H5 bird flu has been detected. This case does not change CDC's overall assessment of the immediate risk to the public's health from H5N1 bird flu, which remains low."
The vast majority of cases have occurred among farmworkers, who are at most risk of being exposed to infected livestock. It is this demographic that federal and state health authorities have sought to target with mitigation and educational resources.
Earlier this year, the CDC made an investment of $10 million into the bird flu response, with $4 million going to the nonprofit National Center For Farmworker Health for training and education on the H5N1 virus.
As part of its effort to reduce the spread of bird flu, California secured a voluntary recall of raw milk products in the state earlier this month due to concerns of possible contamination.
The recalled products came from Raw Farm, LLC and was done after "multiple bird flu virus detections in the company’s milk and dairy." State health officials have discouraged consumption of Raw Farm's dairy products.
"While this voluntary recall only applies to raw whole milk and cream, due to multiple bird flu detections in the company's operation the California Department of Public Health (CDPH) urges consumers to avoid consuming any Raw Farm products for human consumption including raw milk, cream, cheese, and kefir, as well as raw milk pet food topper and pet food kefir marketed to pet owners," the California Department of Public Health said at the time.
Prior to the recall, a suspected case of bird flu is reported to have occurred in a California child shortly after they drank raw milk. The Marin County Health Department said the child had presented at a local emergency department with fever and vomiting.
The child tested positive for Influenza A, a category that includes both seasonal flu and bird flu, and has since recovered. Another child tested positive for a potential case of bird flu last month, with the cause of exposure unclear.
