California Governor Gavin Newsom declared a state of emergency on Wednesday in response to the escalating threat of bird flu, particularly the H5N1 strain. The announcement coincided with the U.S.’s first severe human case of the virus, reported in Louisiana. The declaration aims to accelerate efforts to contain the outbreak, which has raised alarm due to its spread among both animals and humans.
Why Did California Declare a State of Emergency?
The emergency was prompted by the detection of additional cases of H5N1 in dairy cows in Southern California, highlighting the virus’s continued spread beyond its usual avian hosts. Declaring a state of emergency enables the state to unlock funds and resources to address the outbreak more efficiently.
Since bird flu first appeared on U.S. dairy farms in 2022, it has spread to livestock in 16 states. While previous infections in humans had been mild, Louisiana reported a critical case this week—a 65-year-old with pre-existing health conditions who is now hospitalized.
The Centers for Disease Control and Prevention (CDC) confirmed the case, noting the patient had been exposed to infected backyard poultry. “While investigations are ongoing, this marks a significant development in the fight against H5N1,” the CDC stated.
The Spread of H5N1 in the U.S.
The H5N1 strain was first detected in the U.S. in March 2024. Since then, 61 human cases have been reported across seven states, with California accounting for 34. Most cases have involved mild symptoms, but the Louisiana case raises concerns about the virus’s potential severity.
The spread of bird flu to humans has historically been rare, but North America has seen an uptick in cases in recent years. Before 2022, the U.S. had no reported human cases of bird flu.
The virus has also affected Canada, where the first human case of H5N1 was reported in November 2024 in British Columbia.
What Is Bird Flu, and Why Is It Dangerous?
Bird flu, or avian influenza, primarily infects birds but can also spread to other animals, including dairy cows, seals, and domestic pets. The virus occasionally infects humans, though human-to-human transmission has not been documented.
H5N1 is particularly concerning due to its high mortality rate of approximately 60% among humans. The World Health Organization (WHO) reports that since its discovery in the 1990s, H5N1 has infected 860 people globally, resulting in 463 deaths.
The virus can cause severe complications, such as pneumonia and multi-organ failure, making it more deadly than other bird flu strains like H7N9, which has a lower mortality rate of 20%.
How Does Bird Flu Spread?
Bird flu spreads to humans through contact with infected animals or their secretions, including saliva, mucus, and feces. The virus can also become airborne in dust or droplets, posing risks to individuals exposed to contaminated environments.
Despite these risks, the CDC reports no evidence of human-to-human transmission.
Can Bird Flu Spread Through Food?
While there is no evidence that properly cooked poultry transmits bird flu, the CDC advises against consuming raw or undercooked poultry products. Past incidents in Southeast Asia have suggested a link between eating raw poultry and contracting the virus.
Preventing Bird Flu Infections
Health authorities recommend avoiding contact with sick or dead birds, wearing protective gear when handling infected animals, and steering clear of live bird markets in areas experiencing outbreaks.
The CDC also advises against consuming raw milk or eggs, particularly from animals suspected of being infected.
Is There a Vaccine for Bird Flu?
Currently, no human vaccine for bird flu is authorized. However, vaccines for poultry are available and play a key role in controlling outbreaks.
Efforts to develop a human vaccine are underway. The U.S. government has allocated $176 million to Moderna to create a flu vaccine that includes protection against bird flu strains.
A Growing Threat
Bird flu continues to pose a significant global health challenge. The virus, first detected in China in the 1990s, has spread to multiple regions, causing widespread fatalities among birds and sporadic human infections. Recent developments in California and Louisiana underscore the urgency of enhanced surveillance and preventive measures to contain its spread.