First U.S. detection of virulent H5N9 strain, at a California duck farm, draws scrutiny as evidence of genetic reassortment that could trigger human outbreaks.

Both H5N9 and H5N1 were detected at the duck farm in Merced County, according to tests conducted by the US Department of Agriculture (USDA) National Veterinary Services Laboratory. The event began on November 23, with clinical signs that included increased deaths in the ducks.

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

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

Although the virus has been detected at more than 700 California dairies, not a single non-dairy cow has tested positive, experts say.

As egg prices continue to soar across the country, there are new concerns about bird flu as a new strain was discovered at a duck farm.

Rose Acre Farms, the nation's second largest egg producer, said yesterday that tests have confirmed avian flu at its facility in Seymour, Indiana, which could further stretch the supply of eggs as commercial farms in several states continue to battle the spread of the H5N1 virus.

Commercial duck flock in California has tested positive for two strains of avian influenza. On November 23, 2024, two HPAI viruses were identified in samples from a farm rearing meat ducks in Merced County in California. Increased mortality was observed at the premises, leading the state veterinary authority to quarantine the farm.

In Riverside County, 23 dairy and poultry farms including one backyard flock have tested positive for Avian influenza (bird flu), a virus spreading through wild birds around the world causing outbreaks in poultry and dairy cows.

The U.S. is reporting its first confirmed outbreak of H5N9 avian flu at a California duck farm amid a global surge in its sister strain H5N1, according to a report from the Paris-based World Organization for Animal Health (WOAH).

The government is investigating a rare strain of avian flu, H5N9, detected on a duck farm in central California, according to the World Organisation for Animal Health. It marks the first reported outbreak of this strain in U.