Bird Flu Update: US H5N1 News Now

This is your latest bird flu update, tracking H5N1 developments across the United States. I’m your host, and you’re listening to a Quiet Please production.

First, the big picture: the avian influenza H5N1 outbreak continues to evolve, affecting both animals and humans. As of October 2025, the CDC reports a total of 70 confirmed and probable human cases of H5N1 virus infection in the U.S. since 2024. The majority of these cases—41—are linked to dairy herd outbreaks, with 24 tied to poultry operations, and a small number attributed to other animal exposures or unknown sources. Louisiana has reported the first and, so far, only U.S. death from H5N1 bird flu. Importantly, there remains no evidence of person-to-person transmission.

Breaking down the latest cases, California remains the epicenter, with 38 of those 70 human cases—most among dairy workers on affected farms. All known cases in California have involved mild symptoms, primarily eye redness or discharge, and none have required hospitalization. This echoes findings from earlier in the outbreak: illness in humans, while concerning, has generally been mild among those exposed. The CDC emphasizes that the immediate risk to the general public is low, but people with direct exposure to infected animals face a higher risk.

On the animal side, the USDA confirms that highly pathogenic avian influenza has now affected 299 dairy herds across 14 states, with cases continuing to rise, especially in California. Just since April 2024, more than 18.7 million birds in commercial and backyard flocks have been impacted by H5N1, according to USDA data. In recent weeks, new poultry outbreaks have been confirmed in Iowa, Minnesota, and Wisconsin, with several large commercial farms affected. For example, over 520,000 birds were impacted at a single facility in Jefferson County, Wisconsin. Outbreaks are not limited to commercial settings—backyard flocks in states like Montana and North Carolina have also been hit, underscoring the virus’s reach.

In wildlife, more than 200 detections of H5N1 in wild birds were reported in the past week alone, mainly in the Midwest but also in states like Utah, Colorado, and Iowa. The virus has also spilled over into mammals, with recent detections in a domestic cat in Los Angeles County—linked to raw pet food—as well as in house mice and a ground squirrel in North Dakota. The USDA continues active surveillance in wild birds and mammals to better understand the virus’s spread.

On the containment front, the CDC has streamlined its reporting, now releasing monthly updates on the number of people monitored and tested. USDA now provides the latest animal outbreak data directly. There are no major new restrictions for the general public, but enhanced testing, monitoring, and biosecurity remain in place for those working with livestock and poultry. The CDC is also evaluating rapid point-of-care tests for farm and dairy workers and continues genetic sequencing of virus samples to track mutations.

Comparing this to previous weeks, we’re seeing a stabilization in human cases—most new infections are still among workers with direct animal exposure—but ongoing growth in dairy and poultry outbreaks. The number of affected dairy herds and bird flocks continues to climb, though the jump in California dairy cases is especially notable. The virus’s genetic makeup, as sequenced so far, remains clade 2.3.4.4b, closely related to strains found in dairy cattle, with no worrisome changes detected that would increase human-to-human transmission risk.

What does this mean for you? For most Americans, the risk of H5N1 infection remains very low. Those who work with birds, cattle, or other susceptible animals should follow strict biosecurity measures, wear protective equipment, and report any flu-like symptoms to health authorities immediately. The general public...