After the symptoms persisted, the man returned to the hospital on Saturday and was admitted. His wife was hospitalised on Sunday, after she developed a runny nose and a cough.

Although the man stopped going to work on February 7, Chuang said he had gone to a small “family-style” church in Shau Kei Wan two days later.

“We will trace their close contacts and see how many people need to be quarantined,” Chuang said, adding that the man had visited a private clinic before being hospitalised.

But she refused to name the clinic, or the church, or reveal which floor of Ming Kung Mansion the couple live on.

Chuang said the church was usually attended by about 30 people.

“But we have to check with the pastor to see … [if] the attendance is fixed or not. If it is not fixed, we might release the church’s name,” she said.

Taikoo Shing management said it was told by the Department of Health on Sunday that a resident of Ming Kung Mansion – one of the complex’s 61 residential towers – was confirmed to be infected with the virus.

There are more than 12,000 flats in the complex.

“The resident is currently quarantined in hospital for treatment,” it said. “At present, we do not know the specific floor the resident lives on, only that it is in the high zone of the building.”

The management said “intensive cleaning and thorough disinfection” would take place in communal areas of Ming Kung Mansion, including surfaces inside lifts and lobbies.

A source said the latest patient was an employee of architectural firm P&T Group, and worked in his office on the 35th floor of a building at 633 King’s Road.

An internal memo titled “Confirmed Covid-19 infection at P&T office” said the patient had been to work between January 30 and February 6.

“If you worked in close proximity to [the patient] or had other close contact, for example group or face-to-face meetings or lunch, please inform your immediate supervisor urgently,” the memo read.

Staff at the office will work from home until February 23 and are asked to monitor their body temperature.

Meanwhile, the Hospital Authority said a 24-year-old man, the 27th person to be confirmed to have the disease in the city, was discharged on Sunday after testing negative for the virus twice in 24 hours.

Dr Sara Ho Yuen-ha, the authority’s chief manager for patient safety and risk management, said both of the patients that had been discharged had received antiviral medicine, including kaletra and ribavirin.

Put a mask on, Hong Kong welfare chief told

She said the recovery of two younger men suggested the elderly and those with chronic diseases were more likely to develop complications from the disease.

“Those two discharged patients, one of them is 25 years old, the other is 24 years old. So, in general, patients without chronic disease usually recover sooner and better,” Ho said.

The authority said 103 people remained in isolation, including five patients with the virus that were in critical condition and two were in serious condition.

Also on Sunday, Secretary for Development Michael Wong Wai-lun said the Water Supplies Department had increased the amount of residual chlorine from 1 milligram per litre of drinking water to 1.2mg/l, to ensure hygiene and cleanliness.

As part of the treatment process, chlorine is added to drinking water to prevent bacterial growth.

“After increasing the amount of residual chlorine, it is still lower than the World Health Organisation’s suggestion of equal to or lower than 5mg/l [of drinking water] … it is suitable for safe drinking,” Wong wrote in a blog post.