Getting the picture on bird flu

A massive cull of poultry in a northeastern part of China, hit by the country's latest bird flu outbreak, will be carried out by some 1,700 officials and backed up by armed police, who have been sent to the affected county in Liaoning province to slaughter the birds.

In order to get a grasp of the chronology of events it is worth looking at the history of the bird flu virus so far.

It all began in December 2003, when South Korea confirmed a highly contagious type of bird flu was found at a chicken farm near Seoul and a mass cull of poultry began when the virus rapidly spread across the country.

By early January 2004, bird flu was also found on poultry farms in Vietnam.

Then in a surprising announcement in March of the same year China declared it had eradicated bird flu.

In September Thailand apparently found a case where one human probably infected another with bird flu, but this was said to be an isolated incident posing little risk to the population.

In October 2005, following Turkey's report of it's first case of bird flu, the European Commission banned imports of live birds and feathers from Turkey to the 25-nation EU.

This case was later confirmed as the type dangerous to humans, the H5N1 strain.

In the same month British tests identified H5N1 in three ducks found dead in Ceamurlia de Jos in Romania, the first incidence in mainland Europe of the deadly virus.

Also in October Hungary announced that a vaccine against the deadly strain of bird flu had proven effective.

Meanwhile scientists detect the H5 avian flu virus again in wild swans found dead in eastern Croatia, and Britain said that a parrot that died in quarantine in Essex had been found to have the deadly H5N1 strain.

By the end of October, Turkey has ended its quarantine of an area in northwest Turkey near the Aegean Sea where the outbreak of bird flu was identified three weeks earlier, after no further incidence of the virus has been recorded in any other part of the country.

Last week, November 4th, China reports its fourth outbreak of the deadly H5N1 strain of bird flu in a month after nearly 9,000 chickens died in Liaoning province, while in Indonesia the reported death of a woman from bird flu, according to the World Health Organisation, brings the human death toll throughout Asia to 63, comprising 41 in Vietnam, 13 in Thailand, five in Indonesia and four in Cambodia.