Infectious disease expert Ivan Hung on Saturday said Hong Kong could shorten or even dispense with hotel quarantine for incoming travellers, if PCR tests could be arranged more frequently - and with faster results.

Hung, co-convenor of an expert committee that assesses clinical effects of Covid vaccines, told a radio programme authorities could consider shortening the quarantine period to three days, followed by home isolation for four days - provided that they could test inbound travellers every other day efficiently.

"If we could complete the testing as well as the report instead of 24 hours, if we could do it in eight hours, or even four hours... that would definitely prevent infected individuals from going into the community, and I think that will be very important in terms of controlling or containing the current wave of Covid," he said.

"And I believe the laboratories have the capacity of increasing the efficiency of performing PCR testing."

The University of Hong Kong academic said if the pandemic situation is stable, the government could even replace the quarantine policy by testing travellers every day during the first week after their arrival, and then every other day for a period.

Meanwhile, Hung said although the number of hospital admission figures has doubled since early June as coronavirus cases rise, the numbers of serious infections and deaths remains stable.

He said that is probably because nearly 90 percent of people have received two doses of Covid vaccine, or have developed immunity after contracting Covid.

Hung said anti-epidemic measures may not need to be tightened, unless there are more serious cases and Covid-related deaths.