The reported low frequency of bird mortality in the city may have allowed people to breathe a sigh of relief but virologists and veterinary officers all over the country, are still haunted by the possibility of a bird flu outbreak. After the deaths of some local migratory birds were recorded in Delhi around mid-October, similar cases were registered at Rajpura in Punjab and Gwalior in Madhya Pradesh.
The bird watchers suggested food as a source of the infection. “There is a possibility of the H5N8 virus being transmitted through the food that is provided to the birds with or the unhygienic conditions surrounding the water bodies may be a reason. This is a matter that demands investigation as infected birds cannot fly such a long distance,” said Anand Arya, a famous bird watcher in the city.
How did the virus H5N8 enter the city? As Delhi does not have any history of the pathogenic virus, the question regarding the origin of the bird flu virus which claimed the lives of around 92 birds in the national capital, is still unanswered. According to the experts, ascertaining the origin of the virus is crucial to prevent the disease from escalating and handling a potential crisis.
Three major sites in the city – the Delhi Zoological park, Deer Park in Hauz Khas and Shakti Sthal Lake, all, have been closed to the public indefinitely. The disease was first detected at the Delhi Zoo on October 14 with the death of two Pelican birds. The death toll soon reached to 10 within 4-5 days leading to the zoo being shut down for the visitors. At the time of detection of the disease, the zoo had 40 Pelican birds and 20 ducks. “Pelicans are local migratory birds which come here from the southern states. The first flock came here in August; they even laid eggs and produced chickens. If migratory birds were the carriers of the virus, many more would have died,” argued Riyaz Khan, spokesperson of Delhi Zoo.
“The zoo will now be closed indefinitely and any decision regarding re-opening will be made at the high-level meetings,” he informed. He added that the infection was local and is now under control. So far, 14 birds, mostly Pelicans and Ducks have died in the zoo due to the infection of H5N8 virus. The last report of bird death in the zoo was on November 2 when a captive Munia bird died. “This death seems natural,”
The veterinary officers posted at the nodal centre of Delhi government, however, differ with Khan’s argument on the origin of the virus.
“The infection started with local migratory birds particularly Pelicans. They come here from South India. We are considering that these local migratory birds were the carrier of the virus,” said a senior officer with Directorate of Animal Husbandry, Delhi Government.
He, however, added that the report of National Institute of Virology (NIV), Pune will clear the air on the issue. A team of NIV recently visited Delhi Zoo and collected samples, sensitised and trained zoo staff about biosecurity measures against bird flu.
“They will conduct a genome study to ascertain the cause and origin of this H5N8 virus,’ said a senior officer of Delhi government. He further added that a decade back H5N1 infections were reported in and around Delhi but this virus has affected the city for the first time. H5N8 is a subtype of H5N1 virus but the latter is more pathogenic and infects human as well. According to scientists, sometimes the H5N8 is used as an incubator for the highly pathogenic form of H5N1.
The Deer Pak at Hauz Khas is the second water body where deaths of birds due to the influenza virus were reported. The examination of the samples of the dead birds in Jalandhar and Bhopal laboratories confirmed infection by H5N8 virus strain. In terms of casualties, Deer Park was the most infected site in the city as it reported the deaths of 22 birds, which were mostly ducks. Besides ducks, a lake near Shakti Sthal in Paschim Vihar, reported the deaths of three crows. All the samples revealed infection by H5N8, the new virus in the city.
“The virus H5N8 is not harmful to human beings. According to the experts, no human infections have been reported so far worldwide from this virus,” said Delhi Development Minister Gopal Rai who has been monitoring the situation. The government agencies also took samples of poultry from Ghazipur Murga Mandi (Poultry Wholesale) but all the samples tested negative for bird flu.
“If the infection was local the poultry birds would have also been infected. But so far, all infections have been reported to have affected local migratory birds only,” said a senior officer of Delhi government. He further added that it’s a great relief that the poultry birds having escaped the infection or else it would have been a huge loss for the poultry farmers.
The Delhi Government, however, did not take risks and issued ‘mandatory’ for the government agencies owning water bodies in the city besides an ‘advisory’ for the chicken consumers. As per the mandatory, government agencies were asked to spray Anti-Virus – Mycrodacyn on the birds and their habitats.
They were also asked to spray lime around the water bodies and feed multivitamins and garlic to the birds. “The virus is highly responding to Mycrodacyn which contains Sodium Hypochlorite. So we decided to defer the culling of birds and go for their treatment,” added Ryaz Khan.
The government also formed a ten-member team to supervise the operations at Deer Park beside setting up a nodal helpline and monitoring teams in various departments, DDA, NDMC and three MCDs. On October 31, four birds were reported dead due to bird flu but no death of any bird was reported on November 1.
“The situation is almost under controlled in Delhi as we have controlled the death of birds,” said Gopal Rai. In the advisory to the public, the government asked poultry product consumers to ensure that chicken and eggs were boiled properly before being consumed and asked them to report any cases of infection to the government. A team of the Central government’s department of husbandry is also stationed in Delhi Zoo to monitor the situation.
Incidentally, 15 of the 28 Painted Storks died in Gwalior Zoo by October 21. Laboratory reports revealed that all the deaths were due to infection by H5N8 strain, the same virus which was found in Delhi. The same infection was also detected in the samples of the dead birds on October 29 which were found dead in a water body in Rajpura, Punjab. As the infection had been introduced by the local migratory birds which come from Southern parts of the country to Northern region, Odisha government on Monday issued advisory to all chief district medical officers (CDMOs) of the state to take precautions as the state is a preferred location for local migratory birds.