SINGAPORE - People who received the Sinovac Covid-19 jab continue to be excluded from vaccination perks like testing exemptions as there is insufficient data to show how effective the Chinese vaccine is against the Delta strain, said Health Minister Ong Ye Kung.
Mr Ong said there must also be a differentiation between those who received the Sinovac jab and who took the Pfizer-BioNTech and Moderna mRNA vaccines under the national vaccination programme, when Singapore hits the milestone of having half of its population fully vaccinated.
The multi-ministry taskforce on Covid-19, which Mr Ong co-chairs, had on Wednesday (July 7) outlined how restrictions could be further eased for fully vaccinated individuals when this milestone is reached - possibly by the end of the month.
For instance, those fully vaccinated could dine in groups of eight at eateries. However, people who got the Sinovac vaccine will not qualify.
"But once we reach an even higher level of vaccine coverage, we will have stronger herd protection, which means vaccine effectiveness may be less of a factor," Mr Ong said.
"And therefore, in time, we should be able to also be more inclusive in allowing vaccinated people or some partially vaccinated or unvaccinated people to participate in bigger events."
Currently, individuals who have received the Sinovac vaccine are not included in Singapore's national vaccination tally, MOH said on Tuesday. Only those vaccinated with the Moderna and Pfizer/Comirnaty vaccines are part of the tally.
As of July 3, one dose of the Sinovac vaccine has been given to 17,296 people.
However, MOH said those who have received the Sinovac vaccine will have the record reflected in the National Immunisation Registry. It is working on showing the information in the HealthHub mobile app as well.
The first batch of Sinovac vaccines arrived in Singapore on Feb 23, but the vaccine has not yet been approved for use in the national vaccination programme. The Chinese drugmaker has not submitted data which the HSA needs to complete its evaluation of the vaccine's safety and efficacy.
Sinovac is currently being administered in Singapore under the Special Access Route in order to enhance overall vaccination coverage.
A total of 31 private clinics have been selected to administer the Sinovac vaccine, and can also access the National Immunisation Registry.
Mr Ong noted that people have opted for the Sinovac vaccine as they cannot or are uncomfortable with taking mRNA vaccines.
"They too are contributing to the resilience of our society," he said, thanking them for getting inoculated.
"Unfortunately, when we consult the experts, there's just not enough data to show how effective Sinovac is against Delta," he added.
"But I hope this data will emerge soon and allow us to make an assessment."
The Sinovac vaccine has shown variable protection across multiple studies carried out internationally, with the most complete analysis showing an efficacy of 51 per cent. In contrast, the Moderna and Pfizer-BioNTech/Comirnaty vaccines have shown an efficacy rate of around 90 per cent.
Those who were vaccinated with either one or two doses of the mRNA vaccine under the national vaccination programme are not eligible to receive the Sinovac vaccine from the Government's stock, unless they were allergic to the first dose of an mRNA vaccine, MOH said.
Those who had allergic reactions can opt to get the Sinovac jab, but only at a public hospital clinic. This is considering "their previous allergic reaction and a lack of data on the safety profile of receiving Sinovac-CoronaVac following one dose of an mRNA vaccine", the ministry added.
Clinics administering the Sinovac vaccine are required to report adverse events or reactions to the ministry and the Health Sciences Authority (HSA).
Mr Ong said in a written parliamentary reply on Tuesday that two non-serious adverse events have been reported as of June 29.
Separately, the task force said the National Centre for Infectious Diseases and the Ministry of Health had recently concluded a study of about 1,000 household contacts of Covid cases between September 2020 and end May 2021, and found that the efficacy of the mRNA vaccines against the Delta variant is 69 per cent.
This is quite consistent with other figures worldwide, such as in Israel which has reported that the Pfizer-BioNTech vaccine was 64 percent effective against the Delta variant.
Singapore's results will be submitted to international studies, Mr Ong said.
Protection of the vaccines against symptomatic disease was also found to be between 80 and 90 per cent, he added.
Taking mRNA vaccines after getting Sinovac
Those who have taken the Sinovac vaccine or other types of vaccines and still wish to take the Pfizer or Moderna vaccines can also register to do so, though data on the efficacy of using two different vaccines is still lacking.
Such people could have taken the Sinovac vaccines locally or received a dose or doses of a different vaccine elsewhere before returning to Singapore, said Singapore's director of medical services Kenneth Mak.
"There are some theoretical benefits that may suggest that they would get good results. But there isn't much real world data available to confirm this," noted Associate Professor Mak.