Officials downplay risk that tourists will test positive.

A DAY after tests of three Cambodian-Americans believed to have been exposed to influenza A(H1N1) came back negative, authorities in Siem Reap were awaiting results for two Japanese tourists who landed at Siem Reap International Airport with high fevers after a flight from Ho Chi Minh City, health officials said Monday.

The tourists - who had temperature readings of 38 degrees Celsius (100.4 degrees Fahrenheit) - were taken Sunday night to Siem Reap Provincial Hospital and released on Monday, said Iem Pon, the hospital's deputy director.

Iem Pon said Monday that the tourists, a married couple, had not exhibited any other symptoms of the influenza virus, commonly known as swine flu. He said he could not provide their names or ages.

He said blood tests had been sent via taxi on Monday to the Pasteur Institute in Phnom Penh. Dr Sok Touch, director of the Health Ministry's Communicable Diseases Control Department, said Monday evening that officials were still waiting on the results.

Iem Pon said he believed the odds of the tests coming back positive were low.

"I have observed that their health condition is no significant matter," he said.

Iem Pon said the husband had a fever before travelling to Vietnam. He received medical treatment for five days, during which, Iem Pon said, the wife "got diarrhoea because she ate the wrong food".

"When she got diarrhoea, this likely caused her temperature to rise," he said. "But there is no sign of the flu because there is no cough."

I have observed that their health condition is no significant matter.

Japan has confirmed 342 cases of swine flu, according to the government health ministry, AFP reported. There have been no reported fatalities in Japan and the government has said the spread of infections appears to be easing. Media reports on Monday indicated that Vietnam had not seen any cases of the virus.

Past suspected cases

The three people believed to have been exposed to AH1N1 flew from Seattle to Seoul on a flight with a woman who later tested positive for the virus, before flying to Cambodia.

But so far, Cambodia has reported no cases of the virus. Sok Touch said Sunday that increased monitoring at points of entry had allowed officials to prevent introduction of the virus into the Kingdom. All passengers on international flights have been required since last month to fill out a health declaration form upon arrival.

The WHO said Monday the global tally of recorded swine flu cases had risen to 12,515, including 91 deaths, AFP reported.