Luk Chuen House at Lek Yuen Estate in Sha Tin in the New Territories. Photo: Google Maps

The residents of 28 units in a public housing block in Hong Kong’s Sha Tin district were evacuated on Thursday after one more local coronavirus infection was identified in the building.

A 72-year-old man was found to be infected on Thursday and became the seventh patient identified in Luk Chuen House at Lek Yuen Estate in Sha Tin in the New Territories, according to the Center for Health Protection.

On June 1 the man, who resided in unit No 12 in Luk Chuen House, sent a deep-throat saliva sample to the Centre for Health Protection for a test after a cluster of six people in the building were infected. However, his sample tested negative.

On Wednesday, he developed a fever and his latest sample tested positive. The man has diabetes and high blood pressure.

It was possible the coronavirus was spread through water or sewage pipes as the man and two previous patients were living in unit No 12 on different floors, said Chuang Shuk-kwan, director of the Communicable Disease Division at the Centre for Health Protection.

All residents in units No 10 and No 12 were evacuated to a quarantine center, while the government will check the pipes, Chuang said. 

According to the building’s architectural drawing, units No 10 and No 12 share the same sewage pipe. An infected couple were living in a No. 10 unit. 

Tse Chin-wan, the Under Secretary for the Environment, said it was also possible that the patients were infected after touching other public facilities such as mailboxes and door handles.

Chuang added that the Centre for Health Protection had received 1,200 sample bottles from residents in Luk Chuen House, but failed to get in touch with residents in six units. She said the government had issued a mandatory quarantine order to these residents. 

The partial evacuation has been the second one after a similar decision was made in February to evacuate more than 100 people in Hong Mei House, Cheung Hong Estate, Tsing Yi, to a quarantine center.

At that time, two people who lived in the same unit on different floors were identified as infected, indicating that the virus could have been transmitted through sewage pipes. 

The first case in the cluster in Luk Chuen House was a 34-year-old woman whose infection was confirmed on Sunday. Since then, her husband and four other residents have been diagnosed with the virus, along with two of the woman’s colleagues and a paramedic who had treated her.

Earlier this week, health experts said there was no need for the housing block to be evacuated, and it was unlikely that any structural issues with the building were allowing the virus to spread.

Meanwhile, the Centre for Health Protection also identified five imported cases in Hong Kong on Thursday, bringing Hong Kong’s total to date to 1,098. They all arrived in the city from Bangladesh. 

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