Could Europe face similar bird flu outbreak as California?

Avian influenza, commonly referred to as bird flu, has been a common disease among livestock and wild animals alike throughout the years yet the rising cases of humans being infected linked with dramatic financial consequences to the agricultural sector has led governments around the world to grow increasingly wary.  A recent spike in both animal and human cases throughout the US state of California, including the first hospitalization, have led officials to declare a state of emergency on December 18. While experts assure that almost all cases were directly exposed to infected animals, fears of a potential health crisis are spreading throughout the world. 

Californian Governor Gavin Newsom’s office announced the emergency action in a statement, citing the detection of cases in dairy cows on Southern California farms as a signal to intensify monitoring efforts and enhance the coordinated statewide response to control the virus's spread. So far, no human-to-human transmission of the virus has been reported in the U.S., and most infected individuals have had direct contact with sick livestock or poultry. However, as an article by the NPR points out, this week’s severe case in Louisiana involved a resident hospitalized after exposure to sick and dead birds in backyard flocks, raising further concerns.

H5N1, a subtype of avian influenza, primarily spreads among wild and domestic birds but can also infect mammals, including dairy cows, and occasionally humans.

Since the start of 2024, a multistate outbreak of H5N1 has affected 866 dairy herds across the U.S., with approximately 75% of cases concentrated in California, predominantly in the Central Valley. The U.S. Centers for Disease Control and Prevention (CDC) also reported that California accounts for 34 of the nation’s 61 confirmed human bird flu cases, including the first child diagnosed with the virus.

Governor Newsom described the emergency declaration as a precautionary step to equip state and local agencies with the resources and flexibility required to respond swiftly. "While the risk to the public remains low, we will continue to take all necessary steps to prevent the spread of this virus," Newsom assured in his statement.

Avian influenza, commonly found in wild birds, typically circulates globally among migratory populations without causing illness in the birds themselves. However, it is less common for these viruses to jump species and trigger severe outbreaks in other animals, such as poultry.

The current surge in bird flu cases is a continuation of the 2022 outbreak, which has persisted over the past two years in waves. Since the beginning of this year, the virus has claimed the lives of 35 million laying hens, with half of these losses occurring in the last three months alone. In October, the United States Department of Agriculture (USDA) reported a 4% drop in egg production compared to 2023 and has since lowered its future projections for the nation’s egg supply.

The dwindling egg supply has sent prices skyrocketing to record highs in several states. In the Midwest, the cost of a dozen eggs has reached $5.57, while in California, prices have soared to $8.85.

Wild birds infected with the virus are believed to be transmitting it to commercial poultry farms. Despite efforts by farmers to curb the spread—such as culling entire flocks—these measures have so far failed to control the outbreak. Compounding the issue, this year’s bird flu has also impacted cattle, as delivery trucks used to transport poultry are often shared with dairy operations, facilitating the virus's spread across sectors.

While experts caution that it is too early to determine whether the outbreak will become more severe, flu viruses are known to mutate rapidly. Recent research on an H5N1 strain from cows revealed that a single gene mutation could potentially enable human-to-human transmission. If the virus mixes with other seasonal flu strains, it could pose a greater threat.

Despite these possibilities, the CDC maintains that the current risk to the general public remains low. Officials continue to monitor the situation closely to prevent further escalation.

By Nazrin Sadigova