Bird flu virus: What you need to know

UK Daily Mail | October 12, 2005

Britons have been urged to be vigilant against bird flu and to report suspicious bird deaths. The call comes after a ban on the import of live poultry and feathers from Turkey where more than 1,000 cases have been confirmed.

But what is the virus and why has it created such urgency among governments worldwide? See our factfile below to find out.

What is bird flu?

Also known as avian influenza, bird flu is an infectious disease of birds caused by a variant of the standard influenza A virus.

Since mid-December 2003, a growing number of south east Asian countries have reported outbreaks of bird flu in chickens and ducks.

Infections in several species of wild birds and in pigs have also been reported.

Bird flu is unique in that it can be transmitted directly from birds to humans. There are 15 different strains of the virus. It is the H5N1 strain which is infecting humans and causing high death rates.

How does it affect humans?

Humans can catch bird flu directly through close contact with live infected birds and those who work with infected chickens are most at risk.

The virus cannot be passed from human to human. However, experts fear that this may change in the future as the virus develops.

This could result in the infection spreading rapidly across the globe, which was the situation during the great influenza pandemic of 1918-1919.

A completely new influenza virus subtype emerged and spread around the globe in around four to six months, killing an estimated 40�50 million people.

What are the symptoms?

In humans, symptoms include fever sore throats and coughing. People can also develop conjunctivitis. It takes three to five days to develop symptoms.

Chickens may die without showing any symptoms but typically birds suddenly show swelling about the eyes and ear lobes.

How severe is the disease?

This appears to vary. In Hong Kong in 1997 an outbreak of the H591 bird flu virus affected 18 people and caused six deaths.

In the current outbreak in southeast and east Asia (caused by H5N1) human illness is very severe in most cases.

There have so far been 108 cases of H591 flu and 54 deaths recorded in Vietnam, Thailand and Cambodia.

Could bird flu affect flocks in UK?

Bird flu can affect all birds including waterfowl. There was an outbreak of HFN1 flu in wild migratory geese in western China.

Experts have expressed concern that these infected birds could migrate to the UK and pass the disease on to our chickens.

Bird flu could also be spread by the international trade of live chickens. This is why the European Community has banned the import of live poultry and feathers from Turkey where over 1,000 cases of avian flu have been reported.

How serious could this be?

The World Health Organisation has warned that bird flu could be more serious than Sars.

They believe if the virus mutated into a more lethal strain or one that could be passed from human to human the effect could be catastrophic.

The organisation predicted that it could cause some 50,000 deaths in the UK.

If bird flu reached Britain's shores it could already be too late to contain the disease. Professor Neil Ferguson, who led a team investigating the disease said:

"What can we do if it hits our shores? We couldn't stop it. There would be a constant number of new cases and we would be overwhelmed very rapidly."

He added urgent research is under way to see how far deaths could be prevented in the UK should this scenario occur.

What are the current plans to deal with a possible outbreak?

Your usual annual flu vaccination will not provide any protection against avian flu. A new vaccine would need to be produced for this new strain of flu.

There is not yet a definitive vaccine, but prototypes which offer protection against the H5N1 strain are being produced.

However antiviral drugs, which are already available, may help limit symptoms and reduce the chances the disease will spread.

Currently the antiviral drug Tamiflu, made by Swiss-based pharmaceutical company Roche, stands the best chance of curbing pandemic bird flu.

The Government has ordered around 14.6 million courses of the drug Tamiflu - enough to treat around a quarter of the UK's population.

It is effective against multiple strains of influenza and can also be used as a preventative treatment.

Last modified October 15, 2005