Thiruvananthapuram (Kerala): Bird Flu - which primarily affects birds and can also affect humans - has been confirmed again in four states of the country including Kerala.
The disease was earlier detected in the Kuttanad region of the Alappuzha region in Kerala and on Friday, it was detected in the Neendur region in the Kottayam district. If bird flu spreads elsewhere, it could have major repercussions on the poultry sector in Kerala.
Although there are no reports of H5N8 viruses being detected in humans, major caution is necessary because the genetical variant of bird flu viruses can infect humans and cause rapid genetic variation in humans. It is due to this reason that the domestic birds around a one-kilometre radius to the epicentre are being killed.
Here are the key facts related to Bird Flu:
What is Bird Flu?
Avian influenza or bird flu is a bird disease caused by the influenza A virus. Influenza A viruses are classified into subgroups based on the structure of their surface proteins, Hemagglutinin (H) and Neuraminidase (N). This is the basis of names like H1N1 and H5N1. Highly pathogenic avian influenza (HPAI) is a virus that falls into the H subgroups H5 and H7 causing disease. The virus infects domestic birds, including domestic birds such as chickens, ducks, quails, turkeys, geese and pigeons.
What are the symptoms of Bird Flu?
Symptoms of bird flu include blue spots on the jaws and flowers, diarrhea with greenish droppings, bloody discharge from the nose, and redness on the legs and feet. These symptoms may not be present in all infected birds. The main indication of bird flu is often sudden death in numbers without specific symptoms.
Is Bird Flu possible in humans?
Most avian influenza viruses are usually transmitted to birds only. However, there are also viruses that have the potential to transmit from birds to humans and cause disease. Humans are more likely to be infected through close contact with infected birds and contaminated conditions. H5N1 bird flu was first confirmed in humans in Hong Kong in 1997. From 1997 to 2015, 907 cases and 483 deaths were reported in humans due to bird flu.
Avian influenza viruses such as H5N1, H7N9, H7N7 and H9N2 have all been found to be capable of transmitting and infecting humans. Special care should be taken by those who come in contact with infected or dead birds in any way, farmers who use bird droppings as manure, those assigned to disease control activities and those living in diseased areas
But the fact is that bird flu is not one of the most rapidly spreading animal-borne diseases, such as the corona virus or Nipah. Although transmission to humans and human-to-human transmission are extremely rare, mortality rates are as high as 60 per cent.
The World Health Organization (WHO) has warned that bird flu viruses could combine with the influenza viruses found in humans to become a global pandemic, similar to the new genetic antigenic (antigenic shift) Covid-19 virus.
Can Bird Flu affect other animals?
The disease has been reported only in feline animals (cats, leopards and tigers) that feed on infected birds. In 2004, 41 tigers died after eating the meat of infected birds at a zoo in Thailand.
Why are all the domestic birds killed in the disease area?
Infected birds excrete large numbers of avian influenza virus through their noses and droppings. Through direct contact with these, the disease can spread rapidly indirectly through contaminated feed, drinking water, farm equipment, farm workers' clothing and footwear. Infections can be spread over short distances through airborne contaminated water droplets, feathers, and dust particles. Some species of flies and other bird species that come in contact with the droppings of infected birds can also spread the disease to other birds.
Bird flu viruses also have the ability to survive long-term damage in cold climates. Some infected birds (except poultry, quail and turkey) may become permanent carriers of the virus without showing any symptoms. If it spreads out of the disease area, it will be extremely difficult to control. For these reasons, it is of utmost importance that all pathogenic and potentially infected domestic birds within one kilometre of the disease be killed and safely buried.
As bird flu is a global epidemic, there are strict controls and guidelines regarding it. It is part of the national bird flu control protocol to kill and safely bury all birds within a kilometre radius of detection of the disease.
Local authorities are also responsible for the rapid implementation of these disease control measures. The main preventive measure adopted in all bird flu outbreaks around the world is to kill and bury all diseased birds.
In addition to domestic birds, shouldn’t birds such as crows, minnows etc. be killed?
Humans are more likely to come in contact with domestic birds than other birds. Therefore, if domestic birds become infected, the risk of transmitting the disease to humans will increase. This is the main reason for killing all the disease-prone domestic birds in the disease zone.
It is impractical to capture and safely kill native, wild and migratory birds such as mynas, crows and hawks. The only possible preventive measure is to keep domestic birds out of contact with infected birds. For this, effective biosecurity measures must be adopted. Poultry, ducks and other domestic birds should not be allowed to be reared in areas within a radius of 10 km (observation area) for the time being. Feed manure and waste should not be deposited within the farm limits in such a way that they attract migratory birds. Reservoirs and tanks should be securely closed with nets to prevent waterfowl and migratory birds from entering.
How did the Bird Flu virus reach Kerala?
Waterfowl, including migratory birds, are natural carriers of the influenza A virus. The viruses inhabit their airways and esophagus. The bird flu outbreak in Bhubaneswar, Odisha was caused by migratory birds seeking Chilka lake. The outbreak of bird flu in Alappuzha in 2014 and 2016 was also caused by migratory birds. Rarely, however, the virus can be transmitted to these carriers. In Odisha, bird flu was first identified in 2015 in dead crows.
Are there effective vaccines to be administered on birds?
Although different types of vaccines have been developed against the virus, vaccination is not currently recommended in India. Because vaccination does not provide immunity to 100 per cent of birds, there have been cases of flu even after vaccination in countries regularly reported. Although vaccination can exacerbate the disease and significantly reduce mortality, vaccinated chickens are more likely to excrete the virus through secretions and droppings. Therefore, even after vaccination, the same measures have to be taken to kill the birds en masse in the infected areas.
Can Bird Flu affect humans by eating chicken eggs or meat?
Poultry and egg prices have plummeted following the outbreak of bird flu. But the fact is that there is no need to fear in eating thoroughly boiled eggs or meat in non-diseased areas. However, precautions are required when handling meat and eggs.
- When heated to 70 Degrees Celsius, the viruses are killed within 30 minutes
- When cooking the meat, make sure that all the parts of it are well cooked. If cooked well, the pink colour of the chicken will change
- Avoid half-fried or half-cooked meat, half-boiled eggs and bullseye
- As a precaution, wash your hands with soap and water before and after handling raw meat
- Cooking utensils and spoons of uncooked meat in hotels should be cleaned with soap before coming into contact with the stored meat
- Eggshells from infected birds, egg whites and yolks are not free from the bird flu virus. Even if stored in the fridge or freezer, viruses do not die. The virus has the ability to survive for more than a month at a temperature of 4 degrees and for a week at a temperature of 32 degrees. Before using eggs, if there are any droppings on the eggshell, wash and clean them. Hands should be cleaned in the same way
- When feeding pets (dogs, cats, pigs), chicken or its organs, make sure they are well cooked
