Facts About Bird Flu Outbreak In Asia

[george]

Facts about bird flu outbreak in Asia

SINGAPORE, Jan 19 (Reuters) - An eight-year-old girl has been confirmed as the fifth person to die in Vietnam from an outbreak of bird flu, the World Health Organisation said on Monday.

The outbreak in Vietnam, as well as outbreaks in South Korea, Japan and Taiwan, have shaken Asia's poultry industry. Thailand, which produces about one billion chickens a year and exports mainly to Japan and Europe, said it was free of bird flu but was battling an outbreak of poultry cholera.

Here are the main facts about the disease.

WHAT IS BIRD FLU?

The outbreaks in South Korea, Japan and Vietnam have been caused by the H5N1 strain of avian influenza viruses. Avian influenza can range from a mild disease that has only minor effects to a highly infectious fatal version. It spreads in the air and in manure.

It can also be transmitted by contaminated feed, water, equipment and clothing. Clinically normal waterfowl and sea birds may introduce the virus into flocks. Broken contaminated eggs may infect chicks in incubators.

IS BIRD FLU HARMFUL TO HUMANS?

Human fatalities from avian influenza are very rare and were unknown before 1997, when six people in Hong Kong died after being infected with the H5N1 strain.

Early last year, a 33-year-old Hong Kong man contracted the H5N1 virus and died of pneumonia.

In April 2003, a veterinarian who had been working on a Dutch farm infected with bird flu became ill with an H7 strain of the disease and died of pneumonia. The vet did not take medication against avian and human flu. Rules have been tightened to ensure anyone who comes in contact with infected farms does so.

COULD BIRD FLU BECOME A HUMAN EPIDEMIC?

Although avian flu is very infectious in birds, it does not spread easily among humans.

There is a danger, however, that an avian virus mixes with a human influenza and forms a new disease. The new virus could share genetic material from both viruses, being highly infectious like human flu and dangerously fatal like the avian variety. Humans would have no natural defence against it.

New influenza strains have caused pandemics, most recently in 1956-1957 and 1967-1968, killing a combined 4.5 million people.

CLINICAL DIAGNOSIS

The World Organisation for Animal Health says the incubation period for the disease in poultry is 3-5 days. It has various affects on birds, ranging from drastic declines in egg production to sudden deaths. There is no treatment.