Picture of Picture of pathogens on a cutting board

© Dennis Kunkel Microscopy

What is Avian Influenza (AI)?

Picture of Picture of pathogens on a cutting board

© Dennis Kunkel Microscopy

Avian Influenza is an infectious viral disease of birds caused by type 'A' strains of the influenza virus. The flu virus appears naturally among birds. Wild migratory birds such as ducks, geese, gulls and shorebirds are natural carriers of the virus, but are resistant to severe infection from the virus. However, the virus is contagious among domesticated poultry birds and can cause very severe consequences.

How is AI Diagnosed?

AI is diagnosed in humans by isolating the virus from nasal secretions by rapid testing methods.

How is AI Treated?

Ai is usually treated symptomatically including administration of plenty of fluids. Sometimes newer antiviral medications such as ostelmavir (Tamiflu) and zanamavir (Relenza) are used, which however may only be partially effective. People at risk should receive the current season's influenza vaccine only to reduce the possibility of infection with both avian and human influenza.

How is Avian Influenza Transmitted?

Avian Influenza is transmitted by contact with infected birds or surfaces contaminated with nasal secretions or excretions from infected birds.

  • To poultry- Exposure of poultry to infected water fowl
  • Within a flock- Bird to bird by direct contact
  • Farm to farm- Movement of infected poultry, equipment and people

What is High and Low Pathogenicity Amongst AI Viruses?

There are many different serotypes of the Avian Influenza virus depending on the hemagglutinin [HA] and neuraminidase [NA] surface proteins. There are 15 different types of HA and 9 different NA. Based on the combination of these proteins, certain AI are more pathogenic than the rest.

Highly Pathogenic Avian Influenza (HPAI) infections are characterized by a severe and highly contagious illness, affecting most vital organs with mortality rates in domestic flocks approaching 100%.

Low Pathogenicity Avian Influenza (LPAI) on the other hand is the form which is commonly found in the wild bird population. Illness with LPAI is characterized by mild respiratory symptoms and has a low mortality rate in domesticated flocks. However, LPAI like all other influenza viruses has the ability to mutate and become Highly Pathogenic Avian Influenza.

Map of Avian Influenza (AI) cases in birds.

What is the Current Situation of AI?

Areas with confirmed human cases of H5N1 avian influenza since 2003

What is the Incubation Period for AI?

Most cases of AI develop within 3-7 days of exposure to infected birds or contaminated surfaces.

What are the clinical symptoms with AI infection?

People infected with AI manifest with typical flu like symptoms such as fever, cough, sore throat and muscle aches, to eye infections, acute respiratory distress, and pneumonia amongst others.

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