West Bengal on alert as five die in outbreak of animal-borne disease

Kolkata: A rare animal-borne disease, the Nipah virus, has killed five people in West Bengal, prompting authorities to declare a state of alert, health officials said yesterday.

Four members of a family and a health official have died since early April, said Mohan Basu, a doctor in the affected Nadia district of West Bengal.

The Nipah virus is generally spread by fruit bats or pigs. There have been no known cases of human to human infection, according to the World Health Organisation.

The last major Nipah outbreak occurred in Malaysia, where 265 people were infected between 1998 and 1999.

Slaughtered

Some 105 people died and nearly a million pigs, believed to have spread the disease, were slaughtered before the outbreak was controlled.

The virus is capable of infecting a variety of animals and is lethal to about 50 per cent of human patients, causing encephalitis.

No drugs have proved effective in treating Nipah infection.

Nadia district, 121 km from Kolkata, borders Bangladesh, which also had an outbreak of the disease in 2004.

"Initially we thought that the cases were of [mosquito-borne] Dengue, but a test later confirmed that it was Nipah virus that caused the deaths," Basu said.

No cases of human to human infection

• The Nipah virus is generally spread by fruit bats or pigs.
• There have been no known cases of human to human infection.
• The last major Nipah outbreak occurred in Malaysia, between 1998 and 1999.
• The virus is capable of infecting a variety of animals.