Nearly 40,000 chickens have died from a mystery virus in two provinces in southern Vietnam but as many as 400,000 are thought to be infected, officials said Tuesday.
The disease, which first emerged last week, has triggered panic selling of chickens among local farmers in Tien Giang and Long An, raising concerns that it could spread among poulty across other parts of the Mekong Delta region.
"We are taking urgent measures because this epidemic could threaten all the Mekong Delta," said Nguyen Duy Long, an official from the Long An provincial government's veterinary department.
"The virus causes a quick death among infected chickens. It is a very dangerous virus that could also affect other domestic animals," he added.
Long refused to speculate on whether the virus could be the highly contagious bird flu that killed six people in Hong Kong in 1997, and which triggered panic in South Korea following an outbreak there last month.
"We plan to send blood samples to overseas laboratories to determine the type of virus but first we are awaiting a decision from the Ministry of Health," he said.
Health ministry officials could not be contacted for further comment.
"I don't think this is linked to outbreaks of bird flu overseas," said Bui Quang Anh, director of the veterinary department in the Ministry of Agriculture and Rural Development.
"We are investigating carefully the situation and if necessary we will ask for help from foreign specialists. Our first priority at the moment is to prevent any further transmission."