HONG KONG - The total number of people in Hong Kong infected with a novel coronavirus has risen to eight, the Hong Kong Special Administrative Region (HKSAR) government's Department of Health (DH) announced early Monday.

The Centre for Health Protection (CHP) of DH has been investigating three additional imported cases of the novel coronavirus infection since Sunday.

The respiratory samples of the three patients tested positive for the novel coronavirus and all of them are in stable condition

The CHP said at a press conference on Sunday that the first case involves a 47-year-old male with a good past health record who worked in Wuhan, Hubei province, and returned to Hong Kong by train on Thursday.

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The second case involves a 68-year-old woman, also with record of good health, who lives in Shenzhen. She traveled from Shenzhen to Hong Kong's Lo Wu Control Point on Saturday with fever and was intercepted by staff of DH's Port Health Division at the control point. She was immediately taken to hospital for isolation and treatment.

According to the patient, she had visited family members in Wuhan during the incubation period but had neither been exposed to wild animals nor visited any wet markets there.

The third case involves a 64-year-old Wuhan resident whose wife has been confirmed as Hong Kong's third imported case of the novel coronavirus infection. He traveled with his wife to Hong Kong by train on Jan 19 to visit their daughter and son-in-law, and was put into quarantine on Friday as a close contact of his wife. The patient, with underlying illness, developed fever on Saturday night and was transferred to hospital for isolation and treatment.

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The respiratory samples of the three patients tested positive for the novel coronavirus and all of them are in stable condition.

The CHP is continuing its epidemiological investigations and relevant contact tracing of the eight confirmed imported cases in Hong Kong. As of 8:00 pm local time on Sunday, 31 persons with "close contact" and 73 with "other contact" with the confirmed cases have been traced. Eight of them had developed relevant symptoms and were taken to the hospital for isolation, among whom six were discharged later after their laboratory results were confirmed negative for the novel coronavirus.

As of noon on Sunday, the CHP has received reports of a total of 382 cases fulfilling the reporting criteria, including the eight confirmed cases. Of the reported cases, 219 have been ruled out as carrying the novel coronavirus infection, while 155 people remained hospitalized for investigation.