KOLKATA, Jan 22: An outbreak of bird flu in India’s most densely populated state could spiral out of control, officials said on Tuesday, as the disease spread to a seventh district.

The deadly H5N1 strain of bird flu was found among poultry in Malda, infecting seven of the 19 districts in the eastern state of West Bengal, according to state officials.

“There is every chance of the virus spiralling out of hand if it’s too late,” said Sanchita Bakshi, the state health services director.

At least 24 million people live in West Bengal’s seven affected districts. Officials worry the virus could spread to humans and were collecting random blood samples from villagers.

The World Health Organisation has said it was India’s most serious outbreak. Nepal, meanwhile, banned the import of poultry products from neighbour India, as authorities in Bangladesh culled thousands of chickens after the virus spread to Natore district.—Agencies