About a dozen incoming travellers, who arrived on different flights, declared on their health declaration form that they had symptoms, a spokesman for the Department of Health said. Centre for Health Protection officers arranged for them to be hospitalised and most had minor respiratory symptoms.

The Post was told that, according to the departmental operation manager of the Infectious Disease Centre at Princess Margaret, the hospital could not take in new cases as it had already received about 30 referrals from Hong Kong International Airport on Monday.

The Hospital Authority activated its major incident control centre to divert cases to five other public hospitals. They were Prince of Wales, Yan Chai, Tuen Mun and North District hospitals, as well as Caritas Medical Centre.

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One of the cases confirmed earlier on Monday was a 30-year-old man who had recently been in West Africa and Dubai before visiting Chungking Mansions and the Kowloon Mosque in Tsim Sha Tsui. The managers of the mosque said it would be closed until further notice as a precaution.

Eight of the nine cases had recent travel history.

Another was a 26-year-old woman who is a friend of a previously confirmed male patient. The pair visited Hokkaido in Japan between February 26 and March 11. She did not have symptoms but was tested after her travel companion was found to be infected. She was admitted to Prince of Wales Hospital.

A 58-year-old employee, who drove the couple home on their return to Hong Kong, also tested positive. He was the only confirmed case on Monday who did not have a travel history. He was contacted by health officers and sent to hospital on Sunday after his employer was earlier found to be infected.

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Among the other confirmed cases, three had been to Europe and two had taken a holiday in Canada, while another had also visited Africa.

They included a 42-year-old woman who had been on a skiing holiday between March 7 and 14 and developed symptoms while in Austria. She was sent to hospital on Sunday.

A 59-year-old man, who had been to Switzerland between January 22 and February 28 and then to Austria until March 6, was also confirmed as infected after he returned to Hong Kong on March 12.

A 37-year-old man, who had been to the Netherlands for a business trip between February 28 and March 15, was also confirmed with the coronavirus. He developed a fever while overseas. He took flight CX270 back to Hong Kong and was admitted to Kwong Wah Hospital in Yau Ma Tei.

A colleague, who had joined the man between March 2 and 7, also felt discomfort and attended Princess Margaret Hospital in Kwai Chung.

The other patient who visited Africa was a 73-year-old man.

He tested positive in Tuen Mun Hospital, where he was admitted on Sunday on his return from a 20-member package tour to Egypt, which he joined on March 5. He had developed symptoms while on holiday. He went with his wife who had also felt discomfort but had tested negative.

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Meanwhile, two friends, women aged 41 and 45, were confirmed with the virus after returning from a skiing trip in Vancouver. The 41-year-old is a surgeon at Pamela Youde Nethersole Eastern Hospital in Chai Wan. She has not been back to work since returning from her trip and has not experienced any symptoms.

At Monday’s regular press conference on the coronavirus, Dr Chuang Shuk-kwan, head of the communicable disease branch at the Centre for Health Protection, said the health department had collected samples of saliva from residents in flats numbered 13 and 14 at Heng Tai House on Fu Heng Estate in Tai Po, where three people had contracted the virus.

“We have collected samples from about 80 residents, and all of them have tested negative,” she said.

The department expected to collect samples from about 100 people, some of whom had stopped staying in the building, which had slowed down the collection process, Chuang said.

The results from the environmental samples collected from the residential block were expected in another one to two days, she said.

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Hospital Authority chief manager of clinical effectiveness and technology management Dr Linda Yu Wai-ling said three more patients had recovered and been discharged.

Sixty-five patients were still being treated in 12 hospitals. One of them was in critical condition, while others were stable.

Separately, People Power lawmaker Raymond Chan Chi-chuen questioned whether the government was prepared to run the Legislative Council election in September amid the coronavirus outbreak.

“If the [epidemic] situation is similar in September and the number of cases keeps growing, what will be the arrangements for the Legco election?” Chan asked during a panel meeting on Monday.

“Can those under quarantine vote?”

Undersecretary for Constitutional and Mainland Affairs Andy Chan Shui-fu said the government would study emergency response measures, but gave no further details.

“We hope by that time the outbreak will not be too serious and the election can be held,” Chan said, adding that the government would “make every possible preparation”.

Additional reporting by Alvin Lum, Tony Cheung and Sum Lok-kei