Dr Albert Au Ka-wing, a principal medical and health officer at the Centre for Health Protection, said people who tested positive on RATs at home should upload their results and fill out their personal details on the online system as soon as possible.

“The leniency period to submit positive infections using RAT has already passed and we get over several thousand emails per day requesting us to issue a quarantine order or other documents,” Au said.

“We will review these on a case-by-case basis to understand why they were unable to submit their results in a timely manner, whether it was because of technical problems or other issues.”

Au added that authorities would continue to issue relevant documents for residents if their case had been verified using personal details and a photo of the RAT test, but they would not include their infection in the daily infection count as it would be considered a backlogged case.

“We may revise the figures in one go later on,” Au added.

Paul Zimmerman, a councillor for Southern district, urged the government last week to allow people who did not register their previous infections to upload their antibody serology test results instead, in an effort to help residents stuck in vaccine pass limbo and allow officials to better gauge the local epidemic situation.

Under the vaccine pass scheme, those entering 23 types of premises, including restaurants and supermarkets, must have received at least one dose of a Covid-19 vaccine. By April 30, they need to have two doses, and by May 31, three. Recovered Covid-19 patients are exempted from vaccination for up to six months.

Among the cases reported on Tuesday, 16 were imported, including 14 that were detected on arrival at the airport. The rest were identified during hotel quarantine.

Health authorities also announced a ban on four flight routes after passengers tested positive on arrival or failed to provide all the necessary paperwork, triggering a one-week flight suspension.

A Singapore Airlines’ route from Singapore and Malaysia Airlines’ flights from Kuala Lumpur will be banned from landing in Hong Kong from April 5 to 11, while a Qatar Airways route from Doha and Cathay Pacific’s flights from Manchester will be suspended from April 6 to 12.

Authorities have cancelled a total of six airline routes in just three days since changes were made to the flight suspension mechanism on April 1.

Earlier on Tuesday, officials said cameras and monitoring devices would be installed in rooms at a quarantine centre at Penny’s Bay for Diploma of Secondary Education (DSE) candidates infected with Covid-19 or close contacts taking the university entrance examination.

Ricardo Mak King-sang, director at the Hong Kong Examinations and Assessment Authority, revealed on a radio programme that affected residents would begin moving into the facility by the middle of the month.

Two isolation units, one to be used as an exam room and the other for quarantine, will be arranged for each candidate, according to Mak. Each invigilator will monitor about 10 candidates through surveillance cameras, while another will be on patrol to provide immediate help.

“We hope to minimise contact … We also used the same method last year. We think it’s an appropriate arrangement,” Mak said on Tuesday, adding he preferred invigilators at Penny’s Bay to be staff who had recovered from Covid-19.

He said candidates could not withdraw once placed under such arrangements. If a person’s health condition deteriorates and he or she is unable to complete the paper, the results will be calculated based on the completed portions of the test.

Noting the transmission risks at the facility, Mak said infected candidates and those deemed close contacts would be isolated in separate blocks and areas, adding that the rooms prepared were sufficient to accommodate some 1,000 people. Other backup venues will be used if Penny’s Bay is full.

Former secondary school principal Jonathan Lai Ping-wah, a founding member of the Power of Silver Hair, a group of retired educators, said he was confident that around eight to 10 retirees from his organisation could serve as invigilators at the Penny’s Bay exam centres.

He called on the government and exam authorities to implement a closed-loop system so that invigilators could stay at the quarantine facility during the exam period.

“[The closed-loop system] would be in the best interest of our family members and candidates as we could get infected and end up spreading the virus,” he said.

However, officials noted on Monday that such a system would not be enforced since staff currently working at the centre were not required to stay overnight.

Ng Po-shing, guidance consultant at Hok Yau Club, a voluntary organisation offering counselling services for students, welcomed the flexibility for candidates. But he voiced concerns that hotlines and designated taxis for sending students to Penny’s Bay might fall short if infections surged among this group.

He suggested that candidates should closely monitor their own health and start testing themselves with rapid screening kits the day before their paper. “They can also draft a list of necessities that they may need in isolation to better prepare themselves,” he added.

Authorities also said on Monday that students absent for Covid-19-related reasons could apply to be assessed based on other results. The highest level awarded will be revised from 4 to 5 in this year’s exam. Private candidates in such scenarios do not qualify as they do not have school assessments. Their exam fee will be refunded.

The government previously refused to arrange special centres for affected students to sit the DSE paper, saying it was a logistical challenge.

Separately, local health officials and Chinese medicine specialists held a meeting with a group of seven experts in the traditional remedies visiting from mainland China to discuss its uses on Covid-19 patients.

The group is led by Tong Xiaolin, the head of the treatment group at the National Administration of Traditional Chinese Medicine. They have prepared guidelines for prescribing various treatments for different target groups, including asymptomatic carriers, patients with mild symptoms or those admitted to isolation facilities and residents in recovery.

Health chief Sophia Chan Siu-chee called for more Chinese medicine specialists to promote their plans and said the government would step up promotion of the treatments.

Additional reporting by William Yiu