Infectious-disease expert Joseph Tsang Kay-yan said yesterday that authorities might consider asking such individuals to do daily polymerase chain reaction tests.

"It's a balance of risks," he added.

Elderly Commission member Grace Li Fai also weighed in yesterday to say frequent PCR tests are ideal for staffers with amber codes, adding they might consider taking leave during the four-day medical surveillance period following their three-day hotel quarantine as an extra precaution.

However, Li noted, the current manpower shortage at care homes means staff who have just returned to the SAR will still be allowed to work.

Wong Chi-kwong, deputy director of the Office of the Government Chief Information Officer, said authorities have received 2,000 inquiries related to the LeaveHomeSafe app since Tuesday, with 300 of them revolving around the new color-code system.

The chairman of the Hong Kong Direct Subsidy Scheme Schools Council, Dion Chen, called on authorities to clarify the amber-code rules for recently-arrived students who are double-jabbed, including whether they are allowed to take part in maskless extracurricular activities.

The news came as Hong Kong recorded 4,593 new Covid-19 cases - 4,344 local infections and 249 imported - as well as four deaths, taking the fifth-wave death toll to 9,341. Also, a cluster at the Children's Hospital's hematology and oncology department was discovered following the infection of two doctors, a nurse and a patient-care assistant.

Authorities also logged 277 cases across 214 schools, of which four - SKH Tak Tin Lee Shiu Keung Primary School, Hong Kong Baptist University Kindergarten, Christian Alliance HC Chan Primary School and Hong Chi Morninghill School, Tsui Lam - suspended classes with clusters for a week.

Three elderly care homes and two handicapped homes also reported six cases.