The state of Odisha in eastern India has culled more than a thousand chickens after a positive test for the highly pathogenic H5N1 strain of avian influenza, or bird flu, a state government official told Reuters on Sunday.

The epicentre of the outbreak was in the Puri district, about 19 miles from the state capital Bhubaneswar, and follows the recent death of 1,800 birds at a local poultry farm.

“The work is ongoing. We are going to cull about 20,000 birds,” Additional Director of Disease Control Dr Jagannath Nanda told Reuters.

The H5N1 strain is considered highly pathogenic and can also be transmitted to animals such as pigs, horses, large cats, dogs, and occasionally humans.

The spread of the virus is a concern for governments and the poultry industry due to the devastation it can cause to flocks, the possibility of trade restrictions and the risk of human transmission.