A poultry farm in Chhattisgarh’s Koriya district has reported an outbreak of the highly contagious H5N1 bird flu virus, a disease alert by the World Organisation for Animal Health said. The virus has killed 5,634 out of 21,060 birds on a farm in Baikunthpur town while the remaining 15,426 were killed and disposed of.

“H5N1 is a type of influenza virus that causes a highly infectious, severe respiratory disease in birds called avian influenza [or “bird flu”],” according to information on the World Health Organization website. “Human cases of H5N1 avian influenza occur occasionally, but it is difficult to transmit the infection from person to person. When people do become infected, the mortality rate is about 60%.”

Nearly every person contracts the virus because of close contact with infected live or dead birds or environments contaminated with the virus. “The virus does not infect humans easily, and spread from person to person appears to be unusual,” WHO added. “There is no evidence that the disease can be spread to people through properly prepared and thoroughly cooked food.”

In its notification, the World Organisation for Animal Health said that it received the information on Wednesday from Dr Atul Chaturvedi, the secretary of Department of Animal Husbandry and Dairying. It added that weekly follow-up reports will be submitted on the case.

“After some chickens and quails were found dead on December 7 last year in the farm, their samples were collected and sent to local laboratories for testing,” Koriya Veterinary Department Deputy Director Dr RS Baghel told PTI. The samples were then sent to Jabalpur in Madhya Pradesh, where the doctors suggested that it was a respiratory disease. But since the treatment did not work, the samples were sent to the National Institute of High Security Animal Diseases, where, on December 23, the tests were positive for the H5N1 virus.

“Immediately after getting reports of bird flu, we took permission from the Koriya district administration, as per the standard procedure, and culled all 15,426 birds and destroyed 30,000 eggs in the farm and its adjoining areas,” Baghel said. More than 600 of the culled chickens were raised in a one-km radius of the farm. The rearers were compensated, the official said.

“We have completed the culling process and sealed the farm,” Baghel added. “After sanitising the area in 10 km of its radius, we submitted a report to the state’s directorate of veterinary services on Wednesday. No human has been affected due to the outbreak and the situation is under control.”

Workers at the poultry farm in Baikunthpur were given medicines as a precautionary measure, said state Veterinary Services Director CR Prasanna. He added there would be further surveillance in a 10-km radius, which includes about 40 villages, for the next three months.