Avian influenza, popularly known as bird flu, has been reported from Kerala, Rajasthan, Madhya Pradesh, Himachal Pradesh, Haryana, Gujarat and Uttar Pradesh in recent weeks.
In recent, reports of unusual deaths of a large number of birds, including wild ones, started coming in from many States, indicating that the virus is being actively transmitted among various bird groups.
Spread of the disease through outbreaks of H5N1 and H5N8:
- The two virus types identified so far in the outbreaks H5N1 and H5N8 come under the category of Highly Pathogenic Avian Influenza (HPAI), which is of major concern to those keeping birds, because it leads to disease and death of fowl and causes economic havoc. H5N1 is a known threat to humans as well.
- The spread of the disease in a variety of birds in several geographical regions, and the seasonal movement of migratory birds, have prompted the Centre to issue an alert to States to adhere to the National Action Plan for Prevention, Control and Containment of Avian Influenza 2021.
- Internationally, the World Animal Health Information System in December 2020 identified outbreaks of HPAI in Taiwan, Iran, Israel, Japan, South Korea and Vietnam, a dozen European Union countries, Ukraine, Russia and the U.K., leading to a loss of over 4.8 million birds by the end of December 2020.
While avian influenza virus crossing the species barrier and directly infecting humans happens occasionally, human-to-human spread has been rare.
But mutations or genetic reassortment of an avian influenza A virus and a human influenza A virus in a person can create a new influenza A virus that could likely result in sustained transmission between humans, thus increasing the risk of a pandemic influenza.
Hence, all efforts should be directed at stamping out the outbreaks in the affected States. It is also important to undertake genome sequencing of virus samples to track the evolution of the virus.
How serious is avian flu for bird health?
Avian Influenza (AI) is a highly contagious viral disease, affecting a variety of birds, including those connected with human consumption chickens, ducks, turkeys, quails as well as pet birds and wild birds.
The World Organization for Animal Health, which collaborates with the World Health Organization (WHO) and the Food and Agriculture Organization (FAO), says HPAI virus strains H5N1, H5N2, H5N8, H7N8 have been identified in outbreaks, indicating active circulation.
Infection histories point to H5N1 and H7N9 viruses posing a threat to human health as well.
What is the economic impact of bird flu?
- India’s poultry sector, according to the Ministry of Agriculture and Farmers Welfare, is worth Rs.80,000 crore, of which the organised sector represents 80%, and the rest is distributed among unorganised sectors, including backyard poultry-keeping which is crucial for income and nutritional security.
- Exports, mainly focused on West Asia, neighbouring countries and East Asia, were valued at ₹532 crore in 2017, with an emphasis on processed products such as egg powder, yolk powder, pharma ingredients, and chicken products.
- Avian flu is seen as a threat to the further growth of the sector as a whole.
- By the government’s estimates, there are 30 million farmers who keep backyard birds, while small and medium farmers who contribute to aggregators are crucial players in the larger ecosystem. India has a base of over 729 million poultry birds, of which 30% are layers and 40% are broilers, according to the National Action Plan for Egg and Poultry 2022.
- This large base shows that a serious outbreak of HPAI, as was witnessed during 2005-06 in some States, can be catastrophic. During that year, official data put the number of culled birds at over one million.
- In later years, bird flu surfaced in several States, such as Manipur, Assam, West Bengal, Tripura, Bihar, and Kerala, leading to destruction of millions of birds.
- Where culling of birds is undertaken to combat bird flu, the National Action Plan prescribes compensation to be given to farmers at fixed rates. This, once again, underscores the value of prevention to protect captive birds.
Way Forward: Steps can be taken to minimise risk to domestic birds:
- Governments lay down biosecurity measures to keep domestic birds safe from transmission by wild or migratory birds and prevent local spread.
- The protocol involves active surveillance of bird areas to identify emerging outbreaks.
- On the other hand, it is wrong and counterproductive, the FAO cautions, to attempt elimination of wild birds near human settlements through hunting, poisoning, and habitat destruction.
- Such activity disperses wild birds, and the viruses, to new areas. Moreover, hunting of wild birds and the absence of biosecurity measures bring the viruses directly to domestic fowl.
- In the wake of an outbreak in 2020, the U.K. issued advice making it legally necessary for bird-keepers in that country to house them in such a manner that they do not come into contact with wild birds.
The measures, which have general relevance to farmers everywhere, include housing or netting all captive birds, cleansing and disinfecting clothing, footwear and vehicles, reduction of people’s movement in the farm bird areas to reduce contamination.
Eliminating or reducing contact between captive and wild birds, particularly through feed and water storage, and cleansing and disinfecting production areas. The U.K. uses a checklist approach to help farmers with best practices.
In India, the Central government requires veterinary staff to conduct inspections periodically under the Prevention and Control of Infectious and Contagious Diseases in Animals Act, 2009, to catch any signs of disease among birds and other animals early.
However, aquatic wild birds are often found in close proximity to domestic ones in many locations in India, near lakes, dams and reservoirs, making it difficult to achieve segregation. The waterways of Kerala are a good example of this phenomenon.