Migrating bar-headed goose in flight over Basai wetland in Haryana. Photograph: T. R. Shankar Raman/Wikimedia Commons
As avian flu swept by means of India in the direction of the tip of 2020 and early 2021, states scrambled to step up vigil and measures to regulate the unfold of the illness. The 2020/2021 outbreak, marked by the numerous involvement and mortality of untamed birds, has spotlighted the necessity for proactive monitoring of animal illness within the surroundings, conserving unprotected wetland habitats to curb illness unfold, and addressing data gaps just like the wild waterfowl–poultry interface.
Avian Influenza (AI) is a extremely contagious viral illness that impacts each home and wild birds. AI happens worldwide, and totally different strains are extra prevalent in sure areas of the world than others. In accordance with the World Organisation for Animal Well being, wild aquatic birds, equivalent to geese, shorebirds, and wild geese, are the pure reservoirs of influenza A viruses. AI viruses are broadly categorized as low pathogenic AI (LPAI) and extremely pathogenic AI (HPAI) viruses, based mostly on their pathogenicity.
The newest chicken flu outbreak in poultry and wild birds spanned 14 Indian states/union territories from Jammu and Kashmir within the north to Kerala within the south. Haryana, Maharashtra, Punjab, and Kerala have been significantly severely affected. The newest outbreak concerned extremely pathogenic viral strains H5N1 and H5N8, in keeping with the Indian authorities.
“Avian influenza and different zoonotic ailments are within the surroundings, and as human actions encroach pure habitats and environments utilized by wild species, the danger of transmission will increase. We have now reached a stage the place we should proactively improve monitoring of untamed chicken and animal illness in our surroundings to behave as an early warning system of change/arrival of potential ailments,” Taej Mundkur, worldwide waterbird census coordinator and senior technical officer, Wetlands Worldwide (The Netherlands), instructed Mongabay-India.
“Such a surveillance programme ought to be developed by means of organising year-round passive and energetic surveillance at a community of places throughout the nation. This can permit us to be higher ready and reply when a brand new pathogen or new pressure of a identified pathogen arrives,” stated Mundkur, including that the one well being framework, in its broadest sense, goals to enhance the well being of people, agriculture, and wildlife/surroundings and recognises this internet of interconnections and interactions throughout our planet earth.
The Ramsar conference on wetlands and the conference on migratory species and the scientific activity pressure on avian influenza and migratory birds have supplied helpful worldwide steerage on responses/actions to avian influenza within the wild birds-wetland interface, provides Mundkur. They embody making certain that there isn’t a consideration of killing wild birds, spraying poisonous merchandise, or negatively affecting wetland habitats as illness management measures, steerage on illness management measures are related for each Ramsar websites and all different protected and unprotected wetlands and rising biosecurity of wetland web site.
India has emerged as a world hotspot for HPAI H5N1, whereas additionally offering crucial wintering habitat for a lot of species of migratory waterfowl and year-round habitat for a number of resident waterfowl species. The nation lies on the coronary heart of central asian flyway, which spans 30 international locations and covers 279 populations of 182 migratory waterbird species that depend on wetlands alongside the flyway, together with the Pong dam wetlands (Pong lake wildlife sanctuary), a Ramsar web site, the place massive scale mortalities of long-distance migratory birds equivalent to bar-headed geese, first alerted biologists in December 2020.
Experiences of deaths of over 2000 birds at Pong lake in Himachal Pradesh have been adopted by alerts of peacock mortalities in Maharashtra, deaths of lapwings close to Kharo dam in Gujarat’s Junagadh district, and jungle crows in Uttarakhand. Upon affirmation of the avian flu outbreak, a complete of 4,49,271 poultry birds have been culled until February 12, 2021, to regulate the illness unfold, as per the nationwide motion plan for prevention, management, and containment of avian influenza. India’s poultry sector is valued at about Rs. 80,000 crore and employs over 10 lakh farmers.
Addressing data gaps
Information gaps stay within the nature of the wild waterfowl–poultry interface and the sharing of various wetland habitat amongst these birds.
Evolutionary ecologist Farah Ishtiaq underscored the necessity for a well-designed examine to display screen poultry and home waterfowl for low pathogenic viruses. “We lack such knowledge,” Ishtiaq instructed Mongabay-India. “Excessive species range and low water temperature are identified to boost virus survival in sure elements of the world. Nevertheless, within the Indian context, poultry performs an enormous position in circulating the virus all year long. Due to this fact, there have been reviews of outbreaks in non-seasonal time as properly,” added Ishtiaq, senior scientist at Tata Institute for Genetics and Society. She burdened on speedy testing for confirming the reason for dying of untamed birds. “Viruses are very delicate to temperature and RNA degrades actually quick with a rise in temperature. We’d like a simplified system to display screen such samples in real-time because the circumstances are reported to establish the trigger and viral pressure,” stated Ishtiaq.
In accordance with panorama epidemiologist Michael Walsh, co-author of a 2020 examine that systematically investigated the extent of the interface between wild waterfowl and poultry and its affect on the danger of HPAI H5N1 outbreaks in India, there was proof of interplay between poultry and wild waterfowl regarding H5N1 outbreaks.
“Our outcomes confirmed that outbreak danger did enhance with rising poultry density, which is in step with earlier research. Nevertheless, what we additionally confirmed (and what earlier research haven’t explored) is that when you think about the landscapes the place these poultry are held, outbreak danger was truly highest amongst low-density poultry holdings the place poultry have been in prime wild waterfowl habitat. Conversely, outbreak danger was increased amongst high-density poultry holdings solely when these holdings have been in areas the place the poultry have been least prone to come into contact with wild waterfowl,” Walsh, on the College of Sydney, instructed Mongabay-India.
The examine additionally discovered that H5N1 outbreak incidence was increased with better proximity particularly to lakes, rivers, and coastal wetlands. These findings present particular factors within the panorama which may be good targets for interrupting the biking of avian influenza viruses, for instance, by blocking the mixed-use of floor water by home poultry and wild waterfowl.
Whereas the emphasis ought to be on monitoring a number of waterbird websites of native, nationwide, and worldwide significance, surveillance is difficult by the character of the poultry-wildbird-wetlands interface. “The story isn’t easy; home birds in an contaminated space are interacting with wild birds and a few of these birds could also be resident or migratory; the surroundings might be contaminated so you’ve these interactions taking place in an space the place there may be an an infection,” defined Mundkur.
“As poultry themselves don’t fly round, the virus might be carried within the commerce of poultry/poultry merchandise, pet birds, and in tools (fomites) between farms and from the farms to wetlands and to markets. As soon as the virus is launched right into a wetland, it may infect migratory or home birds, and from the place the virus can transfer to a different space by means of native actions of those birds. This will then reinfect poultry or resident birds. Moreover, the virus could also be picked up by predatory birds or raptors in the event that they feed on lifeless or dying contaminated wild birds or poultry.”
There are totally different peculiarities in coping with the virus, and understanding the state of affairs in an space is especially necessary, he noticed.
Farah Ishtiaq provides that unprotected wetlands are below fixed stress from urbanisation and air pollution. With the lack of habitat and enhance in poultry, the wildbird and poultry buffer has lowered and elevated interplay and change of viruses – not simply spillover however in all probability spillback from poultry as properly, she stated.
Kamal Saini, an assistant zoologist at zoological survey of India’s excessive altitude regional centre at Solan, Himachal Pradesh, was a part of the crew that did an preliminary survey of Pong dam wetlands in January following reviews of mass dying of migratory birds. He noticed lifeless bar-headed geese, pochards, pin-tail, black stilt, sand plovers, mallard, spot-billed duck, coot, widespread teal, lapwing, amongst others at Pong.
“We noticed the bar-headed geese attempting to strategy the land from the water, fall, squirm for a couple of minutes, after which drop lifeless. This was earlier than avian influenza was confirmed. The forest division had put in place restrictions. After the birds die, their carcasses are attacked by predators like stray canines, black kites, and tawny eagles; they might carry the virus to distant wild and domesticated animals,” Saini instructed Mongabay-India. So it stays a problem for the division to bury the carcass earlier than these predators assault them. “Moreover, the bar-headed geese which are unable to achieve the financial institution, and die on the water could pose one other menace to people by means of consumption of affected fish,” he stated.
Saini noticed that yearly 1000’s of winter migratory birds, such because the bar-headed goose, make a pit cease at Pong dam and different wetlands on their journey from central Asia, Tibet, Russia, Siberia, Mongolia and any modifications in habitat high quality can push them to search for different habitats.
Bar-headed goose (Anser indicus) is a long-distance migrant to the Indian subcontinent, with its main inhabitants breeding in China. There’s a small breeding inhabitants in Ladakh, Mongolia, and Kyrgyzstan. Migrating bar-headed geese have been reported from many protected and non-protected wetlands of Assam, Himachal Pradesh, Jammu and Kashmir, Uttar Pradesh, Rajasthan, Andhra Pradesh, Odisha, Karnataka, Tamil Nadu, Kerala, and Maharashtra.
“This 12 months their stoppages at Sukhna lake in Chandigarh have been lowered, however they have been seen in good numbers in small ponds in Haryana which signifies that defending habitat high quality even in these small water our bodies is crucial,” stated Saini.
Researchers at Bangor College collaborating with a big worldwide crew of researchers, reported in 2011 that bar-headed geese can fly as much as 6,000 m in solely 8 hours whereas passing over the Himalayan mountain vary – an identical intense climb might kill a human with out prolonged acclimatisation. “When the birds arrive right here they’re subjected to fatigue following their lengthy flight and they’re extra prone to the an infection,” suspects Bivash Pandav, director, Bombay pure historical past society (BNHS), including that the poultry and piggeries are essentially the most prone to the virus.
“Most of those wetlands the place you see migratory birds are unprotected websites, so involving communities in wetland administration is important,” Pandav instructed Mongabay-India.
Pandav reiterates common well being monitoring and sampling of untamed birds in chosen wetland spots to get a way of the illness prevalence and the strains. “In any other case, we attempt to do all this when the mortalities happen. At BNHS, we’ve got been capturing and ringing birds in several elements of the nation. However we are attempting to include the illness monitoring part into our ringing programme. We’re in search of monetary help for the evaluation of the samples,” added Pandav.
This text was first printed on Mongabay India. Learn the unique article.