SINGAPORE, Nov 12 — When enacting Covid-19 regulations earlier this year, regulators indicated an interim time frame of 365 days for a person’s “fully vaccinated” status to remain valid so that vaccination-differentiated safety measures could be implemented, the Ministry of Health (MoH) said today (November 12).
As more data on the protection provided by Covid-19 vaccines over time becomes available, regulators will review this time frame, the ministry added.
The ministry issued this clarification in response to media queries over a reader’s letter to The Straits Times on Wednesday.
The reader, who had combed through the Infectious Diseases (Mass Gathering Testing for Coronavirus Disease 2019) Regulations 2021, noticed that the law states that a person's fully vaccinated status expires 365 plus 14 days after the second dose.
A person is considered fully vaccinated 14 days after the second dose.
The reader asked whether this meant that the Government intends for all Singapore residents to take booster shots to be considered fully vaccinated after a year, and that when the efficacy of the booster jab diminishes, residents would have to take an additional booster to maintain their fully vaccinated status.
In its response, MoH said it regularly reviews the evidence from studies in Singapore and abroad on the protection provided by the Covid-19 vaccines.
It added: “As these studies are ongoing, when enacting the regulations earlier, we had in the interim specified a duration of 365 days... to allow persons who have completed the primary series of their vaccinations to be exempted from vaccination-differentiated safe management measures.”
Exemption from these measures mean that fully vaccinated individuals are allowed to dine in at food and beverage establishments and enter malls and large standalone stores, while those who are unvaccinated cannot.
As more data becomes available, including on the increase in protection provided by booster doses, the Expert Committee on Covid-19 Vaccination (EC19V) will study the evidence and make its recommendations and MoH will review the stipulated time frame, the ministry said.
Both (mRNA) Covid-19 vaccines and non-mRna vaccines approved here are subject to the interim 365-day validity date under the law.
MoH added that while two doses of the messenger ribonucleic acid (mRNA) Covid-19 vaccines provide excellent protection against severe disease, there will be “waning protection against infection”.
“Hence MoH recommends all eligible vaccinated persons to receive their booster doses to improve their protection against Covid-19 infection and reduce transmission,” the ministry said. “This will also further increase protection against severe disease.”
In Singapore, the Covid-19 vaccines were rolled out in late December 2020, with healthcare workers being the first to receive them. They were then progressively given to more frontline workers and then to the elderly in January this year, before being offered to other groups.
Booster doses may be necessary to remain ‘fully-vaccinated’, say experts
Infectious disease experts were split on what the authorities may do in the future when vaccine effectiveness from the two-dose regimen wanes, but they all agreed that there needs to be more studies done to determine how long a person’s fully vaccinated status should last.
Associate Professor Hsu Li Yang, the vice-dean (global health) at National University of Singapore’s (NUS’) Saw Swee Hock School of Public Health, said that there is “every likelihood” that the booster dose, and future booster doses, may be necessary for a person to be considered fully vaccinated.
He added that a one-year expiry tag is “arbitrary but reasonable from a scientific perspective”, considering what we understand of the immune response after Covid-19 vaccination so far.
“This expiry date may be revised as more evidence accumulates,” he added.
Agreeing, Professor Ooi Eng Eong from the Emerging Infectious Diseases programme at Duke-NUS Medical School said that ongoing disease surveillance should help determine when booster shots are necessary.
A rising trend in fully vaccinated people getting Covid-19 would be “the clearest indicator that the protection from vaccination has waned and that booster shots are needed to restore immunity levels”, he said.
He added that whether booster vaccination would in future be required to retain one’s fully vaccinated status will likely depend on multiple factors, such as whether the breakthrough disease is mild or severe, and the capacity of the healthcare system to manage the number of such cases.
Professor Paul Tambyah, president of the Asia Pacific Society of Clinical Microbiology and Infection, also noted that the vaccines were only rolled out earlier this year, and no one other than clinical trial participants have been inoculated for more than a year so far.
“This is a policy decision and I suspect a legal one as a time limit had to be placed on the regulation,” he said. ― TODAY
