KOLKATA (Reuters) - India has put 26 people in isolation with bird flu symptoms and hundreds more people are being monitored, officials said on Friday as Pakistan and Thailand reported outbreaks of bird flu in poultry.
India is battling its worst outbreak of avian influenza, which has spread to 13 of West Bengal's 19 districts. The densely populated state is adjacent to Bangladesh, itself trying to control a major outbreak of bird flu, and has millions of backyard fowl.
India has not reported any human infection of the H5N1 bird flu virus in its four outbreaks of avian influenza since 2006.
"The preliminary tests for bird flu are negative, but more tests are being conducted and the list of sick people reviewed every day," R.S. Shukla, a senior health official, told Reuters.
To the west in neighbouring Pakistan, authorities said bird flu had been detected at a poultry farm on the outskirts of its biggest city, Karachi.
But officials said on Friday there was no likelihood of any human infection.
"We are now monitoring the workers on the farm as well as another one adjacent to it," said an official of the Sindh provincial government.
In Thailand, the virus has been found in a second province in the north.
Tests confirmed the outbreak in Phichit, 345 km (215 miles) north of Bangkok, where about 30 village chickens died last week, Livestock Development Department chief Sakchai Sriboonsue said.
There were four outbreaks in Thailand last year, but no new reports of human infections in the country where H5N1 has killed 17 people since 2003.
In Indonesia, 102 people have died of the disease.
In the latest case, the health ministry said on Friday a woman who had lived near a poultry slaughterhouse on the outskirts of the capital Jakarta died of multiple-organ failure.
The woman, 31, is the seventh person to die of bird flu in Indonesia this year and some experts say the flare-up is caused by a combination of factors such as rainy weather and poor sanitation.
Not including the latest death, bird flu has killed 224 people in a dozen countries since late 2003, the World Health Organisation says.
In West Bengal, veterinary staff have culled 2.6 million birds, completing what officials said was a successful operation that had brought the bird flu situation under control.
The focus now is on hundreds of medical and veterinary workers and villagers who had come into close contact with dead or sick birds. Officials said health staff returning home after the culling operation had been asked to get themselves checked.
Dozens of isolation wards had been created in hospitals in the affected districts to handle any sudden rush of suspected human cases.
Experts fear the H5N1 strain could mutate into a form easily transmitted from person to person, leading to a pandemic, especially in countries such as India where people live in close proximity to backyard poultry.
Health experts also worry about the situation in Bangladesh, a crowded country of 140 million people where bird flu has spread to nearly half of the country's 64 districts.
Livestock officials said bird flu was still spreading and had resurfaced in the Feni district southeast of Bangladesh's capital, Dhaka. The government has ordered culling of all chickens and ducks in one kilometre radius around affected farms.
The virus is threatening the livelihoods of millions of people reliant on the country's poultry industry and driving up food prices.
"Now we are facing a critical situation, as bird flu struck at a time when commodity prices from rice, flour to milk powder and edible oil had already nearly doubled," said Shahedul Alam, a government employee.
Chicken prices in markets in the capital dropped 25 percent over the past two weeks, while the price of eggs has fallen 20 percent or more.
Bird flu has also meant trouble for parts of India's poultry business.
Egg exports from the world's second largest producer have dropped about 50 percent in the past two weeks, leaving the industry with losses of around $20 million, trade officials said.
Additional reporting by Ruma Paul in Dhaka, Panarat Thepgumpanat in Bangkok, Faisal Aziz in Karachi and Mita Valina Liem in Jakarta