People aged 60 to 79 can take second Covid-19 vaccine booster if they wish to

Those aged 60 and above who would like to receive their second booster can walk into any vaccination centre offering mRNA vaccines. PHOTO: ST FILE

SINGAPORE - People aged 60 to 79 can now take a second Covid-19 vaccine booster shot if they wish to, even though the Expert Committee on Covid-19 has yet to recommend that they do so.

The second booster dose should be administered about five months after a person receives the first booster, said Health Minister Ong Ye Kung at a press conference held by the multi-ministry task force on Covid-19 on Friday (April 22).

Those aged 60 and above who would like to receive their second booster can walk in before 7pm to any vaccination centre offering mRNA vaccines.

These boosters are currently recommended for those aged 80 and above, residents of aged-care facilities and medically vulnerable people.

Some 17,200 seniors have taken or booked their second booster within two weeks of the committee's recommendation, representing about 30 per cent of those eligible, with many more in this age group to become eligible in the months ahead, said Mr Ong.

Singapore’s director of medical services Kenneth Mak said local data shows that vaccine effectiveness against severe disease remains high for some time after completing both the primary course and a booster dose.

He added: “Local studies of vaccine effectiveness against severe disease for people above the age of 60 years remains well above 80 per cent and in some stages, reaches 90 per cent at the 120 to 180-day mark after booster vaccination. Vaccine effectiveness against severe disease is also high, following the booster dose, for hospitalisation.” 

He said, however, that some waning of effectiveness against severe disease takes place over time among seniors who have received their boosters.

Data from countries such as Israel with more mature vaccination programmes shows that seniors and the medically vulnerable can get additional protection against severe infection through a second booster, he said. 

“In particular, the overseas data shows the greatest benefit to decreasing severe disease risk is in persons above the age of 80 following the second booster vaccination dose,” said Associate Professor Mak. 

He added that vaccination effectiveness data also shows some benefit from a second booster dose for those aged between 70 and 79, and those aged between 60 and 69 to a slightly lesser extent, although not to the same extent as those in the above-80 group. 

“The incidence of severe infection in these age groups is lower compared with those above 80,” he said. 

Data suggests that the second booster dose is currently not as beneficial for younger age groups – for example, those aged between 12 and 60 – as the risk of getting severe infection is much lower and less associated with the presence of chronic medical conditions that render individuals vulnerable, he added. 

“If we need to provide the second booster dose for the younger population, this is more appropriate as a strategy to augment immune protection at a time when we are experiencing a new wave of a highly transmissible or highly virulent novel variant of concern, rather than at a time when the situation is improving and the community caseload has stabilised,” said Prof Mak. 

The Expert Committee on Covid-19 will also review whether there is a need for more targeted booster vaccinations in sub-populations where the immune protection from earlier primary vaccinations is still not optimal, he added.

The committee has also recommended a booster dose for recovered persons aged 12 and above who have completed their primary vaccination course, in the light of waning immunity. 

The booster should not be delayed beyond nine months after completing the primary vaccination series, and should be received at least 28 days after the infection. 

From June 1, these recovered people will need to receive the booster dose within nine months of their last primary vaccination dose, in order to maintain their vaccinated status.

Individuals may walk into any vaccination centre before 7pm to receive their booster.

The Expert Committee on Covid-19 will review whether there is a need for more targeted booster vaccinations in sub-populations where the immune protection from earlier primary vaccinations is still not optimal. PHOTO: ST FILE

The Ministry of Health said on Friday that booster vaccinations for all recovered migrant workers living in dormitories, as well as non-dormitory dwelling work permit-holder migrant workers in the construction, marine and process sectors will be scheduled and announced later.

Mr Ong added that there are two key considerations when deciding on a suitable time to proactively roll out a second booster to the general population. 

"One, whether subsequent Omicron or new variant waves break out in other countries. When they do, we will then have a good idea when a new wave may emerge in Singapore, and then we roll out a second booster before that happens," he said.

The second indicator is the level of vaccine protection against severe illness in the population who have already had their first booster.

Mr Ong said: "So far, this has been holding up well as vaccine efficacy against severe illness across different age groups continues to stay very high, well above 80 per cent.

"Scientists think that this can hold out for as long as one to two years, maybe even longer. We will watch out for early signs of waning of vaccine efficacy against severe illness, which will indicate the need for a second booster."

In considering which vaccines to use for a second booster for the general population, he said this depends on the nature of the new variant of concern - for instance, if it is a derivative of the Omicron variant with similar characteristics and there is a high chance that current vaccines will continue to confer good protection against the virus.

"However, if the new variant of concern is more dangerous than the Omicron variant, then it may require a different response strategy as far as the second booster is concerned," he said.

Two characteristics can be used to determine if a variant is more dangerous - whether it leads to more severe illnesses and deaths among infected individuals, and if it is more infectious than Omicron and dominates it.

"If it is both... we may then need to hunker down for six months or more while scientists develop a new variant-specific vaccine. This is one of the worst-case scenarios that we need to be psychologically prepared for," he added.

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