BANGKOK: A Chinese woman has been quarantined in Thailand with a mystery strain of coronavirus just days ahead of the Lunar New Year, when Chinese tourists flock to Thailand, authorities said yesterday, the first time it has been detected outside China. A 61-year-old man has died from pneumonia in the central Chinese city of Wuhan after an outbreak of the yet to be identified virus while seven were in critical condition, Wuhan health authorities said on Saturday.

Thai authorities are stepping up monitoring at airports ahead of the Lunar New Year holiday when hundreds of thousands of Chinese tourists are expected to visit. Of 12 passengers quarantined since Jan 3, lab results show that a 61-year-old Chinese woman carried a strain of the coronavirus, the Thai Health Ministry said yesterday.

The woman, who was quarantined on Wednesday, had received treatment and was well enough to return home, the ministry said. "Being able to identify a patient shows that there is efficiency in our monitoring system. We are confident that we can manage the situation," Public Health Minister Anutin Charnvirakul told reporters.

The Chinese outbreak of pneumonia appeared to be linked to a single seafood market in Wuhan and had not so far spread beyond there, the World Health Organization said on Sunday. WHO officials in Thailand were not immediately available for comment yesterday. Thailand receives about 10 million Chinese tourists each year. The Lunar New Year holiday begins on Jan 25.

This comes less than a day after the World Health Organization had stated on Sunday that the pneumonia outbreak which already infected 40 people in China and appears to be linked to a single seafood market in the central city of Wuhan has not spread beyond there.

The cluster of infections had raised fears of a potential epidemic after China said last week that the virus causing it was a previously unknown type but came from the same family of viruses that caused the SARS and MERS epidemics. The seafood market in Wuhan - a major domestic and international transport hub - is now closed and no cases have been reported elsewhere in China or internationally, it said.

"The evidence is highly suggestive that the outbreak is associated with exposures in one seafood market in Wuhan," the WHO statement said, adding that the market was closed on Jan. 1 "At this stage, there is no infection among healthcare workers, and no clear evidence of human to human transmission."

The Wuhan Municipal Health Commission said in a separate statement late on Sunday that four additional patients have been released and that no new cases have been discovered as of Saturday. Another 717 people deemed to be in close contact with the patients remain under medical observation, the authority said.

The WHO said last week that a newly emerging member of the 'coronavirus' family of viruses that caused the deadly Severe Acute Respiratory Syndrome (SARS) and Middle East Respiratory Syndrome (MERS) outbreaks was the likely cause of the outbreak. Coronaviruses can cause infections ranging from the common cold to SARS. Some types cause less serious disease, while others can be far more severe.