Bird flu outbreak and all you need to know about Avian Influenza
Bird flu outbreak and measures taken
- As many as 35,000 chicken have died in 20 days at Melakera in Humnabad taluk, sending shockwaves among those in the poultry farming industry.
Bird flu outbreak outbreak in Karnataka and its effect on poultry sector
- Animal Husbandry Minister A Manju confirmed that the chicken deaths were due to bird flu.
- A series of measures have been put in place by the department of health and family welfare, following reports about the outbreak
- Officials of the department have urged people to eat only completely cooked meat and not consume raw eggs.
- A five-member rapid response team headed by Dr Harshavardhan, a senior official in the department, and comprising doctors, microbiologists and a chief health officer from the Health department has been asked to do a spot inspection
- Measures have been put in place to ensure that the one lakh plus chicken are culled immediately and the eggs are destroyed and buried to contain the spread of the disease. The 50 culling teams which were formed, cleared an area in a 500 to 1,000-metre radius near the private farm. Teams are being trained and given disinfectant apparel for culling. The carcasses would be dumped in a huge pit excavated near the farm’s gate
- As a precautionary measure, those who came in contact with chicken will undergo medical examination and will be given Tamiflu tablets
- An anganwadi in Bidar has been converted into a makeshift hospital to provide treatment should any person be identified with the symptoms.
- Hospitals with ICU facility have been identified in Bidar and Kalaburagi districts and beds have been kept ready to attend to emergency cases.
- The staff of the ‘104’ Arogyavani helpline have been updated about the flu and the precautionary measures to be taken.
- Restrictions have been put on the movement of poultry, eggs and other input from the affected areas.
- Poultry farmers have been advised to take appropriate bio-security measures and approach the Animal Husbandry Department for any assistance
- Around 1.5 lakh chickens are said to be infected with the Avian Influenza and will be culled
The spread of the disease not only entails loss to poultry farmers and the government because of stamping out of infected birds, but also in terms of payment of compensation to farmers and commercial loss in trade
Are Indian’s Safe?
- Indians were less likely to contract the H5N1 virus because of their distinct cooking culture. The virus dies at temperature above 60 degrees Celsius. Since the Indian food is cooked at a higher temperature and is even boiled, the virus likely dies down
- Outside of India, chicken and egg are eaten raw or half-cooked, increasing the chances of the virus spread
What is the symptoms of bird flue?
The typical symptoms of bird flu will be fever, body ache along with sever cold and cough. Sometimes patients may come with rashes too
What to do Should anyone be suspected to be carrying the virus?
Blood samples should be immediately sent to the National Institute of Virology at Nimhans, Bengaluru, for examination. If the sample tests positive, the individual must be quarantined.
About Avian influenza —
- It is known informally as avian flu or bird flu — refers to “influenza caused by viruses adapted to birds.
- “Bird flu” is a phrase similar to “swine flu,” “dog flu,” “horse flu,” or “human flu” in that it refers to an illness caused by any of many different strains of influenza viruses that have adapted to a specific host.
- Out of the three types of influenza viruses (A, B, and C), influenza A virus is a zoonotic infection with a natural reservoir almost entirely in birds
- Avian influenza, for most purposes, refers to the influenza A virus.
- Though influenza A is adapted to birds, it can also stably adapt and sustain person-to person transmission.
- Avian influenza strains are divided into two types based on their pathogenicity: high pathogenicity (HP) or low pathogenicity (LP)
- Avian influenza is most often spread by contact between infected and healthy birds, though can also be spread indirectly through contaminated equipment
- The virus is found in secretions from the nostrils, mouth, and eyes of infected birds as well as their droppings.
- HPAI infection is spread to people often through direct contact with infected poultry, such as during slaughter or plucking
- Though the virus can spread through airborne secretions, the disease itself is not an airborne disease. Highly pathogenic strains spread quickly among flocks and can destroy a flock within 28 hours; the less pathogenic strains may affect egg production but are much less deadly.
- Although it is possible for humans to contract the avian influenza virus from birds, human-to-human contact is much more difficult without prolonged contact. However, public health officials are concerned that strains of avian flu may mutate to become easily transmissible between humans
- Five manmade ecosystems have contributed to modern avian influenza virus ecology: integrated indoor commercial poultry, range-raised commercial poultry, live poultry markets, backyard and hobby flocks, and bird collection and trading systems including cockfighting. Indoor commercial poultry has had the largest impact
H5N1
- The highly pathogenic influenza A virus subtype H5N1 is an emerging avian influenza virus that is causing global concern as a potential pandemic threat.
- It is often referred to simply as “bird flu” or “avian influenza”, even though it is only one of many subtypes.
- Health experts are concerned that the coexistence of human flu viruses and avian flu viruses (especially H5N1) will provide an opportunity for genetic material to be exchanged between species-specific viruses, possibly creating a new virulent influenza strain that is easily transmissible and lethal to humans. The mortality rate for humans with H5N1 is 60%.
Prevention
- Those at high risk include poultry farm workers, animal control workers, wildlife biologists, and ornithologists who handle live birds
- Biosecurity of poultry flocks is important for prevention. Flocks should be isolated from outside birds, especially wild birds, and their waste; vehicles used around the flock should be regularly disinfected and not shared between farms; and birds from slaughter channels should not be returned to the farm.
- With proper infection control and use of personal protective equipment (PPE), the chance for infection is low. Protecting the eyes, nose, mouth, and hands is important for prevention because these are the most common ways for the virus to enter the body.
- Proper reporting of an isolated case can help to prevent spread.
Vaccines:
- Vaccines for poultry have been formulated against several of the avian H5N1 influenza varieties.
- Control measures for HPAI encourage mass vaccinations of poultry though The World Health Organization has compiled a list of known clinical trials of pandemic influenza prototype vaccines, including those against H5N1
Culling
- Culling is used in order to decrease the threat of avian influenza transmission by killing potentially infected birds.
- Zoning strategy which begins with the identification of an infected area (IA) where sick or dead birds have tested positive. All poultry in this zone are culled while the area 1 to 5 km from the outer boundary of the IA is considered the restricted area (RA) placed under strict surveillance.
- The risk of mass culling of birds and the resulting economic impact led farmers who were reluctant to report sick poultry. The culls often preempted actual lab testing for H5N1 as avian flu policy justified sacrificing poultry as a safeguard against HPAI spread
- Not only did culling result in severe economic impacts especially for small scale farmers, culling itself may be an ineffective preventative measure. In the short-term, mass culling achieves it goals of limiting the immediate spread of HPAI, it has been found to impede the evolution of host resistance which is important for the long-term success of HPAI control.
- Mass culling also selects for elevated influenza virulence and results in the greater mortality of birds overall
- Effective culling strategies must be selective as well as considerate of economic impacts to optimize epidemiological control and minimize economic and agricultural destruction.
Precautions
- Do not eat raw or par-cooked chicken
- Do not eat raw or semi-cooked eggs
- Maintain hand hygiene
- Change clothes immediately on coming into contact with poultry
For future avian influenza threats, the WHO suggests a 3 phase, 5 part plan
A. Phase: Pre-pandemic
- Reduce opportunities for human infection
- Strengthen the early warning system
B. Phase: Emergence of a pandemic virus
- Contain or delay spread at the source
C. Phase: Pandemic declared and spreading internationally
- Reduce morbidity, mortality, and social disruption
- Conduct research to guide response measures
