Explained: What is Avian influenza or bird flu? How is it transmitted to humans? How to prevent it

New Delhi, Jan 06: Avian influenza, the bird flu tht has been reported among wild geese in Himachal Pradesh, crows in Rajasthan and Madhya Pradesh and ducks in Kerala can also be transmitted to humans but no such case has been reported so far in India, Sanjeev Balyan minister of state, animal husbandry, dairying and fisheries, told news agency ANI on Wednesday.

The avian influenza has so far been reported from five states -Himachal Pradesh, Haryana, Rajasthan, Madhya Pradesh, and Kerala-Balyan said, adding, "In Haryana, it has been transmitted to poultry as well, otherwise the virus is found in wild and migratory birds."

What is avian influenza or bird flu?

Influenza A virus causes influenza in birds and some mammals, and is the only species of the genus Alphainfluenzavirus of the virus family Orthomyxoviridae.

When and how did the bird flu start infecting humans?

Although avian influenza A viruses usually do not infect people, rare cases of human infection with these viruses have been reported. It was in 1997 when humans are first known to have contracted bird flu following an outbreak in a live bird market of Hong Kong. It was the H5N1 strain of the virus, and 6 out of 18 infected humans died of the disease.

How does it spread to humans?

Infected birds shed avian influenza virus in their saliva, mucous and feces. Human infections with bird flu viruses can happen when enough virus gets into a person's eyes, nose or mouth, or is inhaled.

This can happen when virus is in the air (in droplets or possibly dust) and a person breathes it in, or when a person touches something that has virus on it then touches their mouth, eyes or nose.

It's also possible that some people were infected after swimming or bathing in water contaminated with the droppings of infected birds.

However, people don't catch the virus from eating fully cooked chicken or eggs.

The spread of avian influenza A viruses from one ill person to another has been reported very rarely, and when it has been reported it has been limited, inefficient and not sustained.

How to prevent it?

• Avoid sources of exposure
• People who have had contact with infected birds may be given influenza antiviral drugs preventatively
• Do not eat undercooked or raw poultry or duck
• Avoid eating raw eggs