SINGAPORE - Singapore is studying the possibility of spacing out the time between two doses of the Covid-19 vaccine for the next phase of the national vaccination exercise, so that more people can receive the first dose, said Health Minister Ong Ye Kung on Sunday (May 16).

Experts overseas and in Singapore believe that the two doses of the vaccine can be spaced further apart - up to six to eight weeks instead of three to four weeks currently - without affecting their efficacy, he said at a press conference to announce home-based learning for Singapore schools from Wednesday (May 19).

But those who already have an appointment for their second dose of the vaccine will not be affected. "This is a strategy for phase two of our vaccination exercise moving forward," Mr Ong added.

More details will be announced soon once they are finalised, he added.

He said that the first phase of the vaccination exercise has been focused on those who need it most, such as the more vulnerable population and those working on the front-line in places such as hospitals, sea ports, airport and schools.

"And so for this group, we want to give them the maximum protection, meaning two doses. And today, the progress has been good, so one-quarter of our population today are fully vaccinated - two doses," Mr Ong said.

"MOH has been studying what phase two should look like, and one possibility to think about is... we should try our best to give as many people as possible a good level of protection against Covid-19.

"That means give as many people as possible one dose of Covid-19 vaccination, without reducing the effectiveness, and there has been many international studies and it showed that even with one dose, it confers good protection, without compromising efficacy."

On its website, the Ministry of Health said that two doses of the Pfizer-BioNTech and Moderna vaccines are required to achieve "optimal protection" against Covid-19.

Currently, the two doses of the Pfizer vaccine are required to be taken 21 days apart, while this is 28 days for the Moderna vaccine.

As at May 10, more than 1.8 million people in Singapore have received their first dose of the vaccine, and more than 1.2 million have completed their full vaccination regimen.