SINGAPORE, June 3 — Infectious disease experts believe vaccination is the key prong of Singapore’s long-term Covid-19 strategy, while contact tracing is possibly its weakest link, as it depends on the common sense of individuals to step forward if they suspect they have contracted the virus.
The experts whom TODAY spoke to added that it is crucial that more testing methods — such as do-it-yourself (DIY) test kits — are introduced, as the burden and cost of testing would be shifted away from the Government, making the exercise more sustainable.
The three-pronged strategy of vaccination, contact tracing and testing was laid out by Prime Minister Lee Hsien Loong in a live address on Monday (May 31).
He also shared specific initiatives such as the introduction of over-the-counter DIY test kits and isolating household members of close Covid-19 case contacts to further curb the spread of the virus.
Lee had said that Singapore will have to “learn to carry on with our lives even with Covid-19 in our midst”.
The experts agree that the Covid-19 strategy Lee laid out will prepare Singapore for a future where Covid-19 is endemic.
“This is a pragmatic move, since for a while now, public health experts have already said it will not be possible for the world to eradicate the coronavirus,” said Professor Teo Yik Ying, dean of the Saw Swee Hock School of Public Health at the National University of Singapore (NUS).
“This means we will put in place the necessary measures, including vaccinating the population and planning for the need for booster shots, in order to allow our lives and our economy to regain the normalcy that we had prior to Covid-19.”
Vaccination at the forefront
At the forefront of this three-pronged approach is vaccination, said Professor Dale Fisher, an infectious disease expert from the NUS Yong Loo Lin School of Medicine, as it will lead Singapore to the “end point” of herd immunity.
In his speech, Lee said that Singapore can expect faster vaccine deliveries over the next two months, and that those above 60 can now walk into any vaccination centre to receive their jabs without an appointment.
Students will also be vaccinated in the coming months, he added, after the green light was earlier given for students aged 12 to 15 to receive the Pfizer-BioNTech vaccine.
“The vaccine converts (Covid-19) to a mild disease,” Dr Fisher said, referring to how even those who had contracted the virus while fully vaccinated did not suffer any serious symptoms.
“If a small number of people end up on oxygen, and nobody dies, and the rest have asymptomatic disease, like a sore throat and a runny nose, then there’s no need for (as many) restrictions.”
Agreeing, Dr Teo said that it is clear Singapore intends to rely on mass vaccination as a long-term strategy to cope with Covid-19.
This is evident in how Singapore is allowing World Health Organization-approved vaccines to be offered by private healthcare providers, via a special access route.
This will mean that those with medical conditions such as allergies to the two mRNA vaccines currently approved in Singapore — Pfizer BioNTech and Moderna — will be able to seek alternative Covid-19 vaccines such as those by Johnson & Johnson, AstraZeneca and Sinopharm.
“This will help to address the above population segment that are unable to take the mRNA vaccines,” he said.
The authorities have also allowed pregnant women, mothers who are breastfeeding, cancer patients undergoing active treatment and some with allergies to sign up for the Covid-19 vaccines.
As for what proportion of the population needs to be inoculated to constitute herd immunity, Dr Fisher said that this will depend on Singapore’s “tolerance” levels for Covid-19 cases and deaths.
“Will Singapore get to a point where we’re okay with 100 deaths a year because of Covid-19? Of course, now we’d say no, this is not acceptable.
“But (at the same time), we accept influenza deaths as part of the deal,” he said. “So these conversations will need to happen.”
Contact tracing has its limits
In his address, Lee said that the authorities will be casting the net wider with contact tracing by isolating household members of close contacts.
Experts said that stepping up contact tracing is a sound strategy.
Dr Teo cited an issue where the new viral variants are more transmissible, and where the incubation period may span several days.
“So, household contacts may also be infected and be contagious before contact tracing can catch up,” he said.
“Extending the isolation to household members is precautionary, especially since we know around 70 per cent of transmissions happen within the household, between its members.”
However, contact tracing cannot be overdone as it will be labour intensive and may cause financial difficulties to families, especially those who take home lower salaries.
President of the Asia Pacific Society of Clinical Microbiology and Infection, Professor Paul Tambyah, said that this move could inadvertently deter individuals from coming forward, as they may fear that they will inconvenience their entire households.
“This is especially so with low income individuals, who may be badly affected if they are off work in quarantine or isolation,” he said.
It would also make no sense to go beyond a first-degree contact to also target second- and third-degree contacts.
“If you want to go all the way, that’s called a lockdown,” said Dr Fisher. “Obviously, we don’t want to do that because the social and economic impact is something no one wants.”
More testing to be done by individuals and private sector
Aside from DIY Covid-19 test kits that can be purchased over the counter at pharmacies, Lee said that Singapore residents can expect routine testing to be carried out at work, and in social and community settings.
This will give Singapore the confidence to resume larger scale gatherings, he said.
Experts said that testing, when placed in the hands of individuals and the private sector, can help offload the strain on manpower since most testing has thus far been carried out by the authorities.
Lee had said that various testing methods such as saliva tests, breathalysers and wastewater surveillance have been rolled out or evaluated here.
Dr Teo noted that these alternatives are less time consuming and resource intensive to deploy, compared to the traditional polymerase chain reaction (PCR) tests.
“PCR tests remain the confirmatory test to diagnose an infection,” he said. “However, community screening or event screening can rely on these simpler and quicker tests.”
Lee had said in his speech that individuals such as frontline workers can administer these tests on themselves frequently or even daily.
Dr Leong Hoe Nam, an infectious disease specialist at Mount Elizabeth Novena Hospital, said that although DIY test kits have been shown to be less sensitive compared to PCR tests, repeated testing means that the chance of detecting a positive case is higher.
He added that with testing seen as a personal responsibility, this will relieve the stress on testing capacity on the Government’s part.
“When you push the tests out to the masses, you are empowering the individual, and the corporations and companies to take their own initiative for more testing, thus splitting the costs,” he said.
A new normal by the end of the year?
What will the new normal look like?
Lee said that while Singapore will see small outbreaks of the disease from time to time, there will come a time where people here can gather at entertainment and sports events, go maskless outdoors and visit lower-risk countries.
Dr Fisher said that Singapore can expect to reach this scenario as early as the end of the year, as this aligns with when the vaccine would have been offered to all age groups.
“Once we start to see very few deaths and very few hospitalisations, then we may ease restrictions, and by then Singapore will, step by step, come out of this (pandemic).”
There will also be a day where Singapore may be able to stop case-counting, and instead do macro reports of the total number of Covid-19 patients hospitalised, much like is done with influenza, Dr Fisher added.
But if vaccines are the key to attaining herd immunity, would the ramping up of testing and contact tracing be too resource heavy in the meantime?
No, said Dr Fisher, as there are still the intervening months between now and until Singapore attains herd immunity that the Republic has to weather, and these intermediate strategies will help the country get there safely.
“(Testing and contact tracing) is the approach that we need until we get to that end point,” said Dr Fisher. “If we take our foot off the brakes now, then we are going to have an explosive situation, with only less than 40 per cent of people having had at least one jab.”
Prof Tambyah added that as vaccination rates go up over the next few months, there will likely be a lower demand for measures such as testing.
This will happen as Singapore “gains confidence in the vaccines and the real world data shows how effective they are”, he said. — TODAY