(Agencies)
Updated: 2008-01-26 14:43

KOLKATA - India's worst outbreak of bird flu spread as health authorities battled on Friday to stop it reaching the densely populated city of Kolkata amid heavy rain that hampered culling efforts.

Indian poultry farmer Mazlur Rahaman catches his chickens for culling 24 January 2008. India's worst outbreak of bird flu spread as health authorities battled on Friday to stop it reaching the densely populated city of Kolkata amid heavy rain that hampered culling efforts. [Agencies]

Authorities reported the disease had affected two more districts, bringing the number hit by avian flu to 12 out of West Bengal state's total of 19.

Howra, one of the new districts reporting the disease, neighbours Kolkata. The other district was Purulia on the border with the eastern state of Bihar.

"We're afraid bird flu may spread to many areas -- it has already spread to two more districts," said state animal resources minister Anisur Rahaman in Kolkata, which has 13.2 million people, many of whom live in congested slums.

"We've yet to be able to control this disease," he told AFP, adding new outbreaks were being reported in districts affected earlier.

The disease has spread to more than half of West Bengal state since the deadly H5N1 strain was first confirmed in dead chickens more than a week ago.

"The government has banned the smuggling of chicken to city markets from affected areas," Rahaman said. "All we can do is keep a watch on the markets."

Officials at entry points to Kolkata were disinfecting cars and other vehicles entering the city.

India has not had any human cases of bird flu. But Rahaman said he feared the disease would spread to humans with hundreds of people reporting flu symptoms and children "playing with chickens."

The outbreak was first reported in the village of Margram, 240 kilometres (150 miles) from Kolkata, the capital of the Marxist-ruled eastern state.

Elsewhere in West Bengal, state party workers were to join vets and doctors in a bid to ramp up the culling of hundreds of thousands more chickens after two days of rains slowed operations.

The state says it needs to reach its target of slaughtering at least 2.2 million birds in the state of 80 million people as health authorities seek to control India's third -- and worst -- outbreak of the disease.

Two days of unseasonal rains have turned many rural dirt roads into mud rivers, making it impossible for health teams to reach farms.

Nearly one million chickens have been slaughtered but villagers complained culling teams were leaving the carcasses on roadsides to rot.

Humans typically catch the disease by coming into direct contact with infected poultry, but experts fear the deadly H5N1 strain of the virus may mutate into a form easily transmissible between people.

Migratory birds have been largely blamed for the global spread of the disease, which has killed more than 200 people worldwide since 2003.

Meanwhile, in neighbouring Bangladesh from where the Indian outbreak is believed to have spread, health teams slaughtered nearly 4,600 birds in a border area amid a worsening bird flu situation across the country.

Police and officials sealed off a one square kilometre (0.4 square miles) area at Dinajpur close to the West Bengal border after tests confirmed the H5N1 strain at a farm, government spokesman Salahuddin Khan said.

The new outbreak came as the UN Food and Agriculture Organisation said the bird flu situation had worsened in the impoverished country of 144 million people and posed a danger to public health.

Since Bangladesh's first bird flu outbreak last February, the disease has been detected in 26 out of the country's 64 districts. Officials insist the disease is under control.