A potentially fatal dengue-fever like virus has emerged in the country, according to the Health Ministry.

The Chikungunya virus is thought to be transmitted by the Asian tiger or forest-day mosquito (Aedes albopictus), said Dr Vu Sinh Nam , the deputy head of the Department of Preventive Medicine.

He said the mosquito has black and white striped legs and a black and white body.

Symptoms include a high temperature, rashes, muscular pain and sore eyes.

Nguyen Tran Hien, head of the National Institute of Hygiene and Epidemiology, said the virus had only been detected in patients, not mosquitoes. As a result, he said it could not be certain whether there has been an outbreak of the disease in the country or whether sick patients had brought the virus to Vietnam .

He added that the fever was not considered to be as serious as dengue, but that fatalities had been reported in some countries.

The Health Ministry said there had been 80,000 cases of dengue fever in the country this year that had resulted in 59 deaths.

The ministry said the disease was particularly prevalent in the Central Highlands region where conditions were more favourable to mosquitoes.

Tran Nhu Duong, deputy head of the National Institute of Hygiene and Epidemiology, said research was being conducted on wolbachia bacteria, which shortens the mosquitoes' life span./.