Avian Influenza

Avian Influenza

• The President of the World Health Organization recently issued a warning, urging everyone to get ready for a potential pandemic of bird flu.
• 15 million domestic birds have died as a result of the bird flu pandemic, and 193 million more have been culled since October 2021. It has reached North America, South America, and Central America from Europe and Asia.
• Mammal adaptation: Skunks, a raccoon, and a red foxes are among the mammals that have been verified to have the avian flu by the US Department of Agriculture. It was thought that these mammals had eaten contaminated birds.

About avian influenza:

• Both domestic and wild birds can contract the highly contagious viral disease known as avian influenza (AI), AI viruses have also been isolated from mammalian animals, including humans.
• The viruses that cause this complex disease are classified into a number of subtypes (such as H5N1, H5N3, and H5N8), and their genetic makeup is constantly changing. Although the disease is present everywhere, some places are more likely to experience specific subtypes than others.
• Influenza A viruses can be categorised as either avian influenza (bird flu, subtypes A H5N1 and A H9N2) or swine influenza depending on the origin host (swine flu, subtypes A H1N1 and AH3N2).
• They are separate from viruses that cause human influenza and are difficult for humans to spread.

Types of Influenza Viruses:

• Types A, B, C, and D are the four different subtypes of influenza viruses.
• Humans and a variety of animals are both susceptible to influenza A viruses.
• Humans are exposed to influenza B viruses, which spread and lead to seasonal epidemics. Seals can contract infections, according to recent evidence.
• Both people and pigs can contract influenza C viruses, but illnesses are typically mild and hardly documented.
• Influenza D viruses are known to primarily infect cattle; they are not known to infect or afflict humans.

Transmission and spread:

• AI viruses are excreted in the faeces and respiratory secretions of birds. All of them can be transmitted by coming into touch with the secretions of diseased birds, particularly through faeces or contaminated feed and water.
• Because to AI viruses' resistance, particularly their capacity to endure low temperatures for extended periods of time, they may also be transported on farm equipment and quickly spread from one farm to another.
• Data gathered since 2005, show that high pathogenicity avian influenza spreads seasonally, with the lowest levels in September, a surge in activity in October, and a peak in February.

Infection in Humans:

• Swine, avian, and other zoonotic influenza viruses can infect humans.
• Human infections are typically contracted through close contact with infected animals or polluted settings; these viruses do not yet possess the capacity for long-term human-to-human transmission.
• Serious illnesses include pneumonia, sepsis with shock, acute respiratory distress syndrome, and even death. Severity: These illnesses can range from a moderate upper respiratory tract infection (fever and cough), early sputum production, and rapid progression to severe illness.
• Other described symptoms include conjunctivitis, gastrointestinal issues, encephalitis, and encephalopathy.

Impact:

• Avian influenza outbreaks have the potential to have catastrophic effects on the nation, especially the poultry industry.
• Farmers may encounter a significant amount of flock mortality, with rates frequently hovering around 50%.

Prevention:

• To reduce the danger to humans, illness control in the animal source is essential.
• Tourists and residents of nations with documented outbreaks should stay away from poultry farms, going into places where fowl may be butchered, and coming into touch with any surfaces that look to be contaminated with bird or other animal faeces.
• Quality animal and human population surveillance, in-depth examination of every human infection, and risk-based pandemic preparedness are necessary to reduce the danger to the public's health.

Treatment:

• Certain antiviral medications, most notably neuraminidase inhibitors (oseltamivir, zanamivir), can shorten the time needed for viral replication and increase the likelihood that the virus will survive.
• It is advised to continue treatment for a least of 5 days, although this can be done if necessary to achieve adequate clinical improvement.

India's Situation:

• Between December 2020 and January 2021, new cases of bird flu were discovered in several Indian states, raising concerns all over the nation.
• India was previously deemed clear of the avian influenza (H5N1) virus in 2019, which had also been reported to the International Organization for Animal Health (OIE).
• An intergovernmental organisation called the OIE is in charge of raising animal health standards all over the world. Its main office is in Paris, France.

Virus potential

• Due to its potential to start an influenza pandemic, H5N1 is most important to public health.
• An influenza pandemic happens when a brand-new influenza virus with the capacity to spread from person to person over an extended period of time originates and the general populace has little to no immunity to the infection.
• Between January 2003 and November 2022, there were a total of 868 human cases of H5N1, of which 457 were fatal, according to the WHO.
• But according to the WHO, there is currently no proof that avian flu is spreading from person to person.
• It is unknown if the zoonotic influenza viruses that are presently circulating in pigs, birds, and other animals may cause a pandemic in the future.