A lab technician in Personal Protective Equipment looks at a reagent bottle before performing vaccine tests at a French pharmaceutical company Sanofi's laboratory in Val de Reuil on July 10, 2020. Photo: AFP/Joel Saget

The Hong Kong government will provide a free coronavirus test to everyone in the city from September 1 to track down asymptomatic patients.

Chief Executive Carrie Lam said Friday that everyone should take the test, whether or not they are in a vulnerable group.

Lam dismissed doubts on the effectiveness of mass testing. She said she and other top officials would provide specimens to encourage people to follow suit.

Testing centers will be set up across all districts and run from 8am to 8pm. People will have to make appointments online and register their names, identity card and mobile phone numbers.

Medical workers will take nasal and throat swabs. Those who test negative will be told by SMS, while people who test positive will be contacted by the Department of Health for treatment and isolation.

David Hui Shu-cheong, chairman of the Department of Medicine and Therapeutics at The Chinese University of Hong Kong, said he hoped at least five million people would volunteer for tests.

He told RTHK it would be hard to detect hidden carriers and cut off the chains of transmission if there was a low turnout.

Repeated testing was only needed for those who work in high-risk jobs that involve coming into contact with many people, such as nursing home staff or people in areas where there have been outbreaks.

Hui said people should not be worried that their personal details will be released to the laboratory staff or their samples will be sent to the mainland. He said it would be insufficient to duplicate a person’s DNA if only a little specimen from the upper airway was taken.

Ho Pak-leung, head of the University of Hong Kong’s Center for Infection, said he doubted the effectiveness of the mass tests.

The government would be “wasting bullets” if the plan is not targeted at people with a higher risk of infection, Ho said. Only a few people tested positive after free tests were offered to 40,000 public housing residents in Tsz Wan Shan, where hundreds of cases were reported in July and early August.

Ho said it is better just to test all patients in public hospitals, and carry out repeated tests for staff in elderly care homes and for frontline medics.

Henry Yeung, the president of the Doctors’ Union, suggested that the government could give each citizen a small payment, such as HK$200 (US$25.8) or HK$300, to encourage them to take part in the tests.

Citing his experience delivering sample bottles in some public real estates, Yeung said some people lined up for the kits just to get a complimentary box of face masks, and they threw the test kits away afterwards.

He said some people did not want to get results. He said people think they would affect others if they tested positive.

The test-run by the government was expanded on August 7 to cover some public estates in Wong Tai sin, Tuen Mun and Kwun Tong, and two private buildings in Yau Tsim Mong, involving a total of 46 more buildings and about 86,000 residents. However, as of August 14, about 28,000 specimen samples — less than a third — have been collected from these buildings.

Meanwhile, the Center for Health Protection said 27 cases were reported in the 24 hours on Thursday, including nine imported cases and 18 local infections. The center said infections had been decreasing recently.

The government urged people to bear with the strict social distancing measures in place because the coming week is critical to assess whether the drop in new cases is sustainable.

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