Leung said the jabs are less effective against some mutant strains, but he said people – especially vulnerable groups – should still get inoculated because the vaccines are effective in reducing illness.
“Most vaccines, including nucleic acid, viral vector and inactivated vaccines, seem to be much less effective in preventing infection, but they still offer good protection against severe illness,” he said.
Leung told a radio programme that Hong Kong might reach the 70-percent take-up target by the end of September if the current momentum continues, but said only around 10 percent of those aged 70 or above have been vaccinated, as opposed to more than 50 percent among people aged between 30 and 60.
He said the slow vaccine take-up among the elderly would hinder the city’s vaccination drive, and small outbreaks in care homes or hospitals might also be possible.
Meanwhile, Joseph Tsang, an infectious disease expert from the Medical Association, said the government could look into offering outreach vaccination services for the elderly.
He told another radio programme that authorities may also consider extending operations at community vaccination centres beyond September now that more people are making appointments.
Slightly less than 30 percent of the eligible population have now received two shots of a Covid vaccine.
Seperately, health authorities on Monday reported no new Covid-19 infections.
The Centre for Health Protection said there were a total of 16 cases, all of which were imported or import-related, over the past two weeks.