A civil servant working at the government’s headquarters was suspected to have caught the virus, but tested negative in a preliminary check, sources told the Post.

In a further measure to guard against a wide community outbreak, the government announced that schools would remain closed until at least March 16. Civil servants would continue to work from home until February 23.

These developments came as China’s National Health Commission reported a surge of 15,152 new cases because of a change in the diagnostic criteria. The commission said 1,367 people in the country had died from Covid-19, with 254 new deaths reported on Wednesday.

Of the new infections, 14,840 were reported in Hubei province, the epicentre of the coronavirus epidemic.

Explaining the 10-fold surge over the previous day’s tally, Hubei’s health commission said it had changed the diagnostic criteria to give doctors broader discretion to determine which patients were infected. Health experts had been calling for the move.

Beijing’s purge of officials in Hubei picked up pace, meanwhile, with the removal of the top Communist Party leaders in the region.

The official Xinhua news agency reported Hubei party secretary Jiang Chaoliang had been replaced by Shanghai mayor Ying Yong, 61, a close ally of President Xi Jinping.

Ma Guoqiang, 56, Communist Party leader of the city of Wuhan, where the outbreak started, also lost his job, Xinhua said. He would be replaced by Wang Zhonglin, 57, the party secretary of the city of Jinan, in the eastern province of Shandong.

The replacement of the officials was a response by the central government to public anger over mishandling of the coronavirus outbreak.

The Diamond Princess set sail from Hong Kong on January 25 but has been moored off Japan since February 3 after it emerged that a former passenger, who disembarked in Hong Kong in January, had tested positive for the virus. Japanese authorities placed the ship under quarantine.

On Thursday evening, a Security Bureau spokesman revealed there were 260 Hong Kong passport holders on the cruise liner docked in Yokohama, including the 10 reported as infected.

Earlier, the Centre for Health Protection’s Dr Chuang Shuk-kwan said eight Hongkongers had tested positive, up from three reported earlier.

“On which Hongkongers aboard need help, whether they should be sent back to the city or other arrangements, I know the Constitutional and Mainland Affairs Bureau will work on these areas,” she said.

Japanese authorities said they wanted to move elderly people off the ship if they tested negative for the virus, offering to put them in government-designated accommodation.

But pro-establishment lawmaker Vincent Cheng Wing-shun from the Democratic Alliance for the Betterment and Progress of Hong Kong said Hong Kong people who reached out to him were not in the eligible age group. He urged authorities there to conduct virus tests on passengers as soon as possible and allow them to be quarantined off the ship if their results were negative.

The government said two immigration officers had been deployed to Japan to help Hong Kong passengers. The Immigration Department would try to help them when they were set to end their period of quarantine on February 19.

Hong Kong to extend school closures until March 16 over coronavirus

Retiree Sherry Tsang, 60, had not been tested for the virus and admitted she was worried she might not be able to leave the cruise ship.

But another passenger, also untested for the virus, said, “There is nothing much I can worry about. I will leave in a few days. I do not have much expectation [of the government].”

In a separate development, Chuang said one of three new cases in Hong Kong was connected to an earlier case, both of whom had shared a family meal with 11 others on January 30.

The patient, a 43-year-old man, was an insurance worker who lived in Tuen Mun and worked in Yau Ma Tei. He had no recent travel history and developed a cough on January 29, followed by vomiting and diarrhoea.

“We can see that transmission [of the virus] within families, gatherings or at work is rather high,” Chuang said, urging people to avoid unnecessary activities and maintain personal hygiene.

The man consulted private doctors three times and had continued to work, Chuang said. As a result, about a dozen of his colleagues would have to be quarantined and authorities were still looking for three clients he met during that time.

His fellow diner at the family meal, Hong Kong’s 47th confirmed case, is a resident of Tuen Mun who was admitted to hospital after suffering from a sore throat, chills, a cough and a fever since January 30. His wife and mother, who live with him, have had no symptoms.

Thursday’s other two new cases – a 67-year-old woman and her son, 37 – had also dined with earlier confirmed cases, at the Star Seafood Restaurant in North Point on the evening of January 26.

The woman lives in Mount Parker Lodge, Quarry Bay during the week but stays with her son in Heung Hoi Mansion in Wan Chai on the weekend. She developed a cough on January 31 and a fever and chills the next day. She made three visits to private doctors on January 31, February 3 and 7 before going to Ruttonjee Hospital in Wan Chai on Wednesday.

Her close contacts – her daughter, son-in-law, grandson, granddaughter and domestic helper – did not show symptoms and would be put into quarantine.

Her son, who works for the Social Welfare Department, developed a fever on February 8 and consulted a private doctor the next day. He sought treatment at the same hospital as his mother on the same day.

The department said on Thursday night it would close its office in Tung Che Commercial Centre, Sai Ying Pun, until further notice for complete disinfection. The office had only offered limited services since Monday.

The duo are in stable condition and had no travel history during the incubation period.

The three earlier cases they dined with were all connected to Hong Mei House in Tsing Yi, which underwent a partial evacuation earlier this week when it was feared the virus may have been spread through a ventilation system.

Chuang said one family ordered to leave Hong Mei House had remained, refusing to go to the quarantine centre. The authorities had allowed them to stay in their home after a thorough disinfection was carried out in their flat. Their pipes were also checked and since they seemed in order, the home was considered low-risk, Chuang added.

She said more than 100 residents of the building were in quarantine and samples collected around the block had tested negative for the virus.

As of Thursday afternoon, 126 people were in isolation, according to the Hospital Authority.

Among those infected, four were in critical condition, five were serious and the rest were stable.

Meanwhile, a medical source said a 37-year-old woman, Hong Kong’s 11th patient confirmed infected with the virus, could be discharged soon.

Health officials said earlier that patients would only be discharged after testing negative for the virus twice and would be required to return for further examination.

The woman, who worked in Hong Kong, fell ill after spending time with her parents, who flew to the city on January 22 from Wuhan.

Earlier in the day, two government insiders said a support worker from the Security Bureau was in an isolation ward at Prince of Wales Hospital in Sha Tin, listed as a suspected coronavirus victim and awaiting test results.

A government spokesman said late on Thursday evening a member of staff working in the government headquarters was admitted to hospital and tested negative for the virus.

The usual protocol of environmental disinfection and putting close contacts into quarantine applied should a government worker be found with the virus, Chuang said.