Scientists have sounded an alert over the outbreak of Nipah virus, a deadly lung and brain disease currently spreading into rural India and Bangladesh, by warning that the viruses are being passed through sweet food and domestic animals.
Nipah virus is rapidly spreading into rural India and Bangladesh, killing up to three-quarters of the infected people.
"People are catching this disease by drinking date palm juice or probably by eating fruit contaminated by the virus, or through contact with infected animals," said Dr Jahangir Hossain, a scientist working in the Dhaka Hospital at the International Centre for Diarrheal Disease Research in Bangladesh (ICDDR,B).
"We have seen nine outbreaks in Bangladesh since 2001, which killed 40-100% of the people who were infected," he added.
Nipah virus emerged from Singapore and Malaysia ten years ago when pigs on farms ate fruit, which had been bitten by infected fruit bats.
The pigs developed coughs and breathing difficulties that turned out to be a deadly epidemic across Asia due to the pig trade. Pig farmers and abattoir workers became infected from sick pigs.
"Three outbreaks in Bangladesh were caused when people ate fresh date palm sap, a local sweet delicacy, which had been contaminated by bats," said Hossain.
"Because both people and animals in Bangladesh often eat fresh date palm sap and fruits which have been bitten by bats, contaminated food and domestic animals form an important transmission pathway for Nipah virus to infect people," he added.
The researchers are now working on to identify the factors, which could help prevent virus transmission in the future.
"We are working with local date palm sap collectors to learn about traditional practices that prevent bats from getting at and contaminating the sap", he said.
"If we can identify the factors that allow the virus to be passed from bats to humans so frequently, we might be able to help intervene and interfere with the transmission pathways," he added.