AVIAN INFLUENZA - SCIENCE AND TECHNOLOGY

News: Bird culling begins in Kottayam

 

What's in the news?

       With bird flu spreading to more parts of the district, the authorities have started the culling of more than 7,000 birds in Kottayam in a bid to keep the disease under control.

       The presence of the avian influenza virus (H5N1) was confirmed in two duck farms in Arpookara and Neendoor and a broiler chicken farm in Vechoor recently.

 

Bird Flu:

       Bird flu or avian influenza is a disease caused by avian influenza Type A viruses found naturally in wild birds worldwide.

 

Avian Influenza Virus:

       Avian Influenza type A viruses are classified based on two proteins on their surfaces – Hemagglutinin (HA) and Neuraminidase (NA).

       There are about 18 HA subtypes and 11 NA subtypes.

       Several combinations of these two proteins are possible e.g., H5N1, H7N2, H9N6, H17N10, etc.

 

Infected population:

       The virus can infect domestic poultry including chickens, ducks, turkeys and there have been reports of H5N1 infection among pigs, cats, and even tigers in Thailand zoos.

 

Transmission to humans:

       Bird flu viruses do not normally infect humans. However, sporadic human infections with bird flu viruses have occurred.

       The most common route of virus transmission is direct contact - when a person comes in close contact with infected birds, either dead or alive.

       Humans can also be affected if they come in contact with contaminated surfaces or air near the infected poultry.

       There is no sufficient evidence suggesting the spread of the virus through properly cooked meat.

 

Symptoms:

According to the US CDC, the reported signs and symptoms of avian influenza A virus infections in humans have ranged from mild to severe influenza-like illness.

       Fever, cough, sore throat, muscle aches, nausea, abdominal pain, diarrhea, vomiting.

       Severe respiratory illness (e.g., shortness of breath, difficulty breathing, pneumonia, acute respiratory distress, viral pneumonia, respiratory failure).

       Neurologic changes (altered mental status, seizures).

 

Risk groups:

       Children and adults below 40 were seen to be the most affected and mortality was high in 10-19 years olds.

 

Measures against Bird Flu:

       Revised Action Plan for Prevention, Control & Containment of Avian Influenza (2021)

       Opting Culling method.

       Cleansing and disinfecting and reduction of people’s movement.

       Vaccination to humans: Avian Influenza vaccine is available outside India e.g. the USA has developed the vaccine for Human infection.