As many as 300 migratory demoiselle cranes, popularly known as Kurjan, have died in Rajasthan over the last 10 days because of bird flu, forest officials said on Monday, adding that the death rate was falling every day.
Bird flu or avian flu is an influenza that spreads among birds. In rare cases, it can affect humans.
Initially, experts felt the deaths were caused by Ranikhet disease, known in the West as Newcastle disease. But a Bhopal-based lab report later confirmed that the migratory birds were dying in Rajasthan due to bird flu, officials said.
Veterinary doctors and those involved in rescue operations have so far tested negative for bird flu.
Authorities in the state have faced criticism over the handling of the situation, especially with the disposing of the bodies.
A senior government official who wished not to be named said, “We should have waited for the lab report before acting, but the pressure was so intense to take action.”
The first death of a demoiselle crane was reported on November 5 in Kaparda village in Jodhpur, from where around 180 bodies have been recovered so far.
Officials said the number of daily deaths among the migratory birds in the area have come down to four to five fatalities per day from 30-40 in the initial days of the outbreak.
The outbreak hasn’t yet been recorded in the Sardar Samand Lake area in Pali district, around 36km from Kaparda.
A total of 134 migratory demoiselle cranes died in the last three days, including 22 on Sunday, according to Vinod Kumar Kalra, joint director of the state’s animal husbandry department. Viscera samples of the dead birds have been sent to a lab, he said.
Dr Gyan Prakash, a veterinary expert at Kaparda, said a report from a lab in Bhopal has confirmed that the birds died from avian flu, after which certain protocols were put in place, such as disinfecting the area and carefully disposing of the bodies.
Prakash also said no such case has so far been reported in Khichan village, which currently has over 14,000 migratory birds. Khichan is around 180km from Jodhpur city.
Prakash said that local birds were aware of Kaparda’s saline water, hence only the migratory demoiselle cranes were dying from bird flu.
He said the presence of black wind stilt in the area, a bird that is seen as a pollution marker as it feeds on algae and weeds that grow in polluted water, indicated that the water in Kaparda was polluted.
Prakash speculates it’s possible that the bird flu came from Japan, where an outbreak was reported in October, with migratory birds likely carrying the disease to Rajasthan.
On protocols that are followed in the event of a bird flu outbreak, retired professor and microbiologist Dr AK Kataria said the process starts the moment symptoms are spotted prima facie.
“Everyone, especially those involved in the process, need to be cautious when the disease is undiagnosed as it can be fatal and communicable. If it is bird flu, it can be fatal,” Dr Kataria said.
In November 2019, carcasses of close to 18,000 migratory birds were found at Rajasthan’s Sambhar Lake, the largest inland salt lake in India. The deaths were caused by avian botulism, a neuromuscular illness of birds.