Singapore yesterday confirmed a local coronavirus case linked to a meeting at the Grand Hyatt Singapore as the World Health Organisation (WHO) began an investigation into the business gathering.

The meeting is now linked to four confirmed cases in three countries.

The Singaporean, a 27-year-old man, is one of four Singapore residents referred to the National Centre for Infectious Diseases after attending the meeting.

He had no history of recent travel to China.

The cases provide more evidence that the virus is spreading through human-to-human contact outside China, which the WHO has said is deeply concerning and could signal a much larger outbreak.

"WHO is coordinating with relevant ministries of health in relation to it," said spokesman Olivia Lawe-Davies. "As countries are stepping up surveillance, the detection of more cases of local transmission can be expected."

Malaysia and South Korea also have cases linked to the 109-strong meeting in Singapore of staff from a multinational sales firm, where one Chinese delegate was from the Chinese city of Wuhan, the epicentre of the coronavirus outbreak.

Malaysia said yesterday that the sister of an infected Malaysian man who attended the meeting at the Grand Hyatt Singapore has been infected as well. South Korea has two cases linked to the event.

The authorities have not revealed the name of the company, although South Korea has said it is an international sales firm.

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Malaysia offered the first revelation when it confirmed the case of the 41-year-old citizen who had attended the meeting at the plush hotel near the Orchard Road shopping district.

South Korea then confirmed two cases involving its citizens who were also at the meeting.

The Koreans and the Malaysian shared a buffet meal during the conference, South Korean media said.

Singapore said earlier that virus symptoms had surfaced in four of the 15 local staff of the company, and that all 94 overseas attendees had left Singapore.

The hotel will carry out "thorough sanitisation and deep cleaning" of guest rooms that were potentially affected and will monitor staff and guests for symptoms, its general manager Willi Martin said.

REUTERS