Arkansas, a major US chicken producer, has reported its first outbreak of lethal avian influenza in a commercial poultry flock in a year, as the nation sees an uptick in cases, reported Reuters.

The outbreak is set to expand export restrictions on US poultry in major producing states as buyers limit purchases from infected areas.

The disease infected a flock of 31,600 breeder pullets, or young hens, used to produce meat in Madison County, Arkansas, the US government said this week.

Arkansas, the third biggest producer of chickens raised for meat, last suffered an outbreak on a commercial farm in October 2022 in the same county.

Avian influenza has wiped out more than 60 million US chickens, turkeys and other birds since 2022 and has spread to new parts of the world. Cases tend to increase during the spring and autumn migration of wild birds that transmit the virus, and infected poultry flocks are culled to prevent the disease from spreading.

"We have taken immediate action to contain this disease," Arkansas Agriculture Secretary Wes Ward said.

Alabama, the second biggest US producer of chickens for meat, last week confirmed its first outbreak at a commercial farm, in a flock of 296,500 game birds, according to the US government. Mexico, the biggest export market for US chicken, quickly blocked poultry shipments from the infected county.

The US in October confirmed its first case of avian influenza on any commercial poultry farm since April in South Dakota. Minnesota, the biggest US turkey producer, and Iowa reported fresh outbreaks as well.

The World Organization for Animal Health said on Thursday that Mexico reported its first outbreak this season on a farm, just a month after the country declared it was free of the disease.