Singapore—Speaking at a virtual news conference on Thursday (Apr 22), the Ministry of Health’s (MOH) Kenneth Mak said a booster vaccine shot may be needed to protect people against Covid-19 eighteen months after they get their vaccinations, to combat waning immunity.
The booster shot would protect also individuals against the new variants of the virus, he added.
Associate Professor Mak, MOH’s director of medical services, said, “While vaccination gives a clear protective benefit to all who may be exposed to COVID-19 infection, the vaccination is not 100 per cent protective.”
A year and a half after vaccinations, how protected a person may be is “still a relatively uncertain situation,” he added.
Singapore, along with other countries, is therefore studying the need for an eventual booster shot.
The booster shot would be necessary because vaccinated people, explained Associate Professor Mak, may experience “gradually waning immune protection,” as evidenced by those who have been reinfected with the virus after they recovered.
If tests show that the immune levels of people who have been vaccinated “start to drift downwards,” he added, “it would then be the right time to start planning to vaccinate these people as well.”
Furthermore, the new variants that have emerged over the past few months, especially the UK, Indian and South African variants, may be able to withstand the current vaccines.
As of Tuesday (Apr 20) there have been 350 local and imported cases of different variants in the country.
Associate Professor Mak added, “It may well be the case that we need booster vaccine doses to augment the immunity that we already have from the previous vaccinations and to give us additional protection, particularly against these variants of concern.”
Workers who have recovered from the infection may be given a single booster shot, said Mr Tan See Leng, the Second Minister for Manpower.
“Studies have shown that there is a boosting of the immunity after you’ve given them a single shot, so we do have plans for that.”
At the moment, only two Covid-19 vaccines have been authorized for use in Singapore— Pfizer-BioNTech and Moderna.
The Pfizer-BioNTech has shown to be effective against the Covid-19 variant found in Brazil, but not as effective against the variant from South Africa.
Studies have also shown that two Moderna vaccines being developed are shown to protect against the South African and Brazilian variants when administered to mice.
Almost 850,000 people in Singapore have been fully vaccinated against Covid-19, or 14.9 per cent of the population. Over 1.35 million people in the country have received at least one vaccination shot.
Health Minister Gan Kim Yong urged people to get their vaccine shots, even as he acknowledged limited supplies due to the worldwide shortage.
“I therefore encourage all medically eligible Singaporeans and long-term residents to go for vaccination when it is offered to you,” Mr Gan said.
/TISG
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