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 newly identified strain of bird flu, H5N9, discovered at a California duck farm, has prompted concerns about the possibility of a larger outbreak, The Washington Post reported Jan. 29. Health experts are monitoring the situation, particularly the potential for genetic mutations that could make the virus more easily transmissible among humans.

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

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

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

The different, rarer sub-type of the common avian influenza H5N1 virus has been found on a duck farm in Merced County, California, according to the World Organization for Animal Health.

This week, the World Organization for Animal Health reported that it had been notified by the USDA that a November outbreak of highly pathogenic avian influenza on a California duck farm was caused by a strain not before seen in the United States: H5N9.

H5N9 is a rare strain of avian influenza. H5N1 is the more ... "Whether this novel H5N9 virus will cause human infections from its avian host and become a pandemic subtype is not known yet.

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

The H5N1 virus has a ways to go before it can successfully jump to humans but that it doesn’t reduce the threat it poses.