U.S – The United States Department of Agriculture’s (USDA) Animal and Plant Health Inspection Service (APHIS) has announced an outbreak of highly pathogenic avian influenza (HPAI) among a commercial egg laying flock in Weld County, Colorado.
This case affecting about 1,928,000 hens, marks the third case of HPAI in a commercial poultry flock in Colorado in 2022, and the second in a commercial egg operation in the state.
HPAI is a serious disease caused by influenza Type A virus (influenza A) and requires rapid response because it is highly contagious and often fatal.
It can infect poultry, such as chickens and turkeys, as well as free-flying waterfowl like ducks, geese and shorebirds.
The virus was also confirmed in another Weld County layer flock on April 29, having affected 1,366,200 birds.
In addition, on April 19 Montrose county also reported HPAI in a commercial broiler breeder operation involving about 58,000 chickens.
Colorado has also had confirmed cases of HPAI in two backyard flocks and at one animal rescue and rehabilitation center.
Prior to the most recent Weld County case, the last time a commercial flock in the U.S. was affected by HPAI was June 2, when a commercial duck operation in Berks County, Pennsylvania was stricken.
Berks County is also where the previously most recent case of HPAI in a commercial egg operation was confirmed. The case, which involved 79,000 hens, was confirmed on May 17.
Early in February this year, a commercial turkey flock in Dubois County, Indiana, was also affected, making it the first confirmed case of HPAI in commercial poultry in the United States since 2020.
The case in Indiana known as H5N1 strain followed earlier detection of the virus in wild birds that were hunted in Virginia, North Carolina, South Carolina, Maryland and Florida.
It marked Indiana’s first case of H5N1 infection amongst commercial poultry since 2016, as reported by Reuters. During that 2016 outbreak, more than a dozen commercial flocks in the state were affected and upwards of 400,000 birds were culled, according to the IndyStar.
With the latest HPAI case, the number of commercial birds affected by the virus in 2022 has reached 39,364,200.
To date in 2022, HPAI has been confirmed in commercial poultry in the states of Michigan, Wisconsin, Oklahoma, Minnesota, North Dakota, South Dakota, Nebraska, Kansas, Iowa, Missouri, Kentucky, Indiana, Colorado, North Carolina, Pennsylvania, Delaware, Maryland and Utah.
The virus has also been found in commercial game bird operations in Texas, New York and South Dakota.