SACRAMENTO, Calif. (AP) — California Gov. Gavin Newsom declared a state of emergency Wednesday to combat a surging bird flu outbreak in dairy cattle, as federal health officials simultaneously reported the nation’s first severe human case in Louisiana.
The emergency declaration comes as California grapples with more than 300 infected dairy herds in the past month, making it the epicenter of the nation’s outbreak. The state currently accounts for roughly half of all human infections in the U.S.
“This proclamation is a targeted action to ensure government agencies have the resources and flexibility they need,” Newsom said. “While the risk to the public remains low, we will continue to take all necessary steps to prevent the spread of this virus.”
The Centers for Disease Control and Prevention revealed that a Louisiana resident was hospitalized after exposure to sick and dead birds in backyard flocks. Genetic sequencing identified the infection as the H5N1 virus’s D1.1 genotype, distinct from the strain affecting dairy cattle.
Dr. Demetre Daskalakis of the CDC emphasized during a press briefing that while this case doesn’t change their assessment of low public risk, it highlights historical concerns. “Bird flu has a well-established history of leading to severe illness and death over the past 20 years in other countries,” he said.
The CDC reports more than 60 confirmed human infections nationwide, though researchers suggest this could be an undercount. Most cases linked to dairy cattle have resulted in mild illnesses.
The Louisiana case follows a recent hospitalization in British Columbia, where a teenager contracted the same D1.1 strain through an undetermined source. The CDC is conducting additional genetic sequencing to monitor for mutations that could indicate increased human transmission risk.
While most infections stem from direct contact with sick animals, particularly among dairy workers exposed to infected cattle milk, several cases in California and Missouri have emerged without clear transmission sources. However, officials stress there’s no evidence of sustained human-to-human spread.
Scientists warn that unchecked spread in dairy cattle increases the risk of the virus developing dangerous mutations. The emergency declaration aims to expand monitoring and coordinate a more comprehensive statewide response to contain the outbreak.
The CDC continues surveillance efforts, particularly focusing on cases without clear exposure sources and genetic changes that could signal enhanced human transmission capability.
“Infections without a clear source of exposure do occur,” Daskalakis noted. “Neither these cases nor the cases with known animal or animal products exposure have resulted in human-to-human transmission.”
