A new strain of H5N9 bird flu was detected at a commercial duck operation in California's Merced County. All the ducks were euthanized.

H5N9 is a rare subtype of the influenza A virus that can cause highly pathogenic avian influenza (HPAI), also known as bird flu. It's a reassortment strain that originated from the H5N1, H7N9, and H9N2 subtypes.

A pandemic is not inevitable, scientists say. But the outbreak has passed worrisome milestones in recent weeks, including cattle that may have been reinfected.

The Centers for Disease Control and Prevention today released an advisory recommending clinicians expedite subtyping of type A influenza samples from hospitalized patients, particularly individuals in an intensive care unit.

A new strain of a highly pathogenic and rare strain of bird flu has been reported on a duck farm in central California.

Since early 2024, the U.S. has logged 66 human cases of H5N1. Scientists are keeping a watchful eye on the virus’s spread as we enter a new year.

The findings come at a time when outbreaks of bird flu -- a different subtype of the ... of the highly pathogenic avian influenza (HPAI) H5N1 influenza virus currently circulating

A subtype of bird flu caused by avian influenza A (H5) virus has been spreading worldwide ... including avian influenza A(H5N1), have gained the ability to spread easily and sustainably among ...

U.S. authorities also detected the more common H5N1 strain on the same farm in Merced County, California, they said in a report to Paris-based WOAH, adding that the almost 119,000 birds on the

A subtype of bird flu caused by avian influenza A (H5) virus has been spreading worldwide ... including avian influenza A(H5N1), have gained the ability to spread easily and sustainably among ...

US officials are investigating the appearance of a strain of bird flu identified in the US for the first time, a worrying sign that the virus is evolving in ways that could make it harder to

A US government memo ordering a halt to communication with global health bodies has concerned scientists as a strain of bird flu is detected in California for the first time.