Repeated outbreaks in Bengal worrisome

New Delhi, January 19, 2009

With four outbreaks of bird flu among poultry in 14 of the West Bengal’s 19 districts in less than a year, the risk of people getting infected with the virus that kills two in three people it infects has risen manifold.

“Tracking the progression of the disease in Indonesia and elsewhere has shown that it takes an average of one year and nine months of exposure to the virus for the infection to build up to concentrations that can infect humans. India managed to contain the outbreaks so far, but recurrence in West Bengal within six months is a cause for worry,” said NK Ganguly, distinguished biotechnology fellow, government of India, and scientific adviser to the ministry of health.

Those living in the districts of Malda, Darjeeling, Murshidabad, South 24 Parganas and Birbhum face the worse risk because these districts have had more than one outbreak in a year.

Outbreaks of the highly-pathogenic H5N1 virus that causes bird flu was first reported in the districts of Birbhum and Dakhsin Dinajpur on January 15, 2008, after which the virus spread to 14 districts over the next five months.

After a gap of six months, Malda reported its second outbreak — and the state’s third — on December 15, followed by Darjeeling on January 2, 2009.

Over the last year, 5 million birds were slaughtered to control the virus. Assam and Tripura are the other two states that reported outbreaks in 2008.

The health ministry shot off letters to the governments of West Bengal, Orissa, Assam, Tripura, Chhattisgarh and Bihar late last month, alerting them to the dangers of human infection.

“India has not reported human cases yet, but states bordering Bangladesh, where the virus has become entrenched, need to be very alert,” Union Health Minister Anbumani Ramadoss told.

What’s worrying is that in West Bengal, ducks are not culled. “Ducks have become reservoirs of the virus because they carry it without developing symptoms or falling sick. Infected ducks pose a threat not only to other animals but also humans,” said Ganguly.
hat-tip Muscade