Sewage pipes at Fung Chak House in Choi Wan Estate are contaminated with Covid-19 virus. Photo: Google Maps

Hundreds of Hong Kong residents in a Kowloon building have to be tested after Covid-19 was found in its sewage.

Scientists from the University of Hong Kong found the virus in four samples from the sewage pipes of Fung Chak House in Choi Wan Estate between December 23 and 27, Environment Secretary Wong Nam-sing said on Monday.

As the results showed possible asymptomatic patients in the building, the government decided to issue a mandatory virus test notice to the those who visited the building for more than two hours since December 15, Wong said.

Gabriel Leung, Dean of the Li Ka Shing Faculty of Medicine at the University of Hong Kong, said his team had collected samples from Fung Chak House after 15 cases were reported at the neighbouring Ming Lai House in the same estate. Leung said some excrement of infected patients drained to the sewage pipes but the risk of the virus spreading to the housing units remained small.

Leung added that similar tests had been done to the samples from three other estates with virus outbreaks but none of the samples tested positive.

A drainage services assistant director, Eddie Pak, warned that any coronavirus in sewage could spread through the air from leaking pipes or pipes that had been modified irregularly.

The Center for Health Protection said 61 cases, one imported and 60 local infections, were recorded on Sunday. Of the local patients, 19 had no known source. More than 40 people tested positive preliminarily on Monday.

Six more infected people were identified at the United Christian Hospital on Sunday after a cluster of 15 people tested positive on Saturday.

Government expert adviser Yuen Kwok-yung said on Saturday that an 84-year-old super spreader had caused a coronavirus outbreak at the palliative care ward at the United Christian Hospital.

Hospital officials said the woman was admitted on December 15 and tested negative for the coronavirus. She was later transferred to the palliative care ward due to a bed shortage before she was found to be carrying the virus.

Last Friday, the government announced that all incoming travelers, except those from mainland China, should be isolated in hotels for 21 days, instead of 14 days.

Some newly arrived domestic workers were stuck at the Hong Kong airport on the same day as they could not present proof that their employers had reserved 21-day hotel accommodation for them. Their employers complained that they failed to extend their reservations by seven more days as the 36 hotels designated by the government suddenly raised prices.

Cheung Kit-man, chairman of the Hong Kong Employment Agencies Association, said about 1,000 domestic workers could not leave for Hong Kong these few days due to the sudden increase of the quarantine period.

The Hong Kong government said Monday it was concerned that the 36 hotels had increased their prices after the increase in quarantine period was announced. It said it would require these hotels to freeze their prices.

An 18-year-old student tested positive on Sunday, the 19th day after he came back to Hong Kong from the United Kingdom. His CT value exceeded 30, showing that the amount of virus in his body was low and not enough to infect others.

David Hui Shu-cheong, chairman of the Department of Medicine and Therapeutics at The Chinese University of Hong Kong, said the student was categorised as an imported case but he could have been infected locally. Hui said more investigations should be done in this case as about 2 to 5% of the patients had their incubation periods more than 14 days.

Meanwhile, the government on Sunday conducted mobile broadcasts in popular gathering places of foreign domestic workers to call upon them to comply with the anti-epidemic regulations on the prohibition of group gatherings of more than two people and mask-wearing in public places. 

These include Tamar Park in Admiralty, Victoria Park in Causeway Bay, footbridge near Fa Yuen Street in Mong Kok, the Cultural Centre in Tsim Sha Tsui, various places at Central and Tseung Kwan O. Police issued 43 fixed penalty notices of HK$5,000 (US$645) in these places on Sunday.

An official from the Labor Department delivers a leaflet to a domestic worker in Mong Kok on December 27, 2020. Photo: HK Govt

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