As optimism rises over the promise of Covid-19 vaccines, experts have warned that even the best vaccine will be no panacea alone and must be combined with effective treatments, as well as individual responsibility, to reduce the spread of the virus.
Professor Ooi Eng Eong, deputy director of Duke-NUS' emerging infectious diseases programme, one of three experts at a Straits Times Covid-19 webinar yesterday, said: "At the end of the day, the control of Covid isn't going to rely on vaccines, it isn't going to rely on drugs, it isn't going to rely on measures like social distancing alone.
"It's probably a combination of everything that we can throw at this virus."
Attracting over 1,000 participants, the 11/2-hour session focused on lessons learnt in six months of Covid-19 in Singapore and how these would shape the way forward in tackling the viral disease.
Singapore, with 49,098 cases and 27 deaths, is in the midst of a cautious reopening as the spread appears to be under control.
Globally, the pandemic is still in full force, with 15.4 million people infected, and more than 630,000 dead, lending urgency in the race for a solution.
Professor Dale Fisher, a senior infectious diseases expert at the National University Hospital, said there has been a lot of hype recently about positive developments in vaccine research.
With 130 candidates, of which 24 are in clinical trial stages, Prof Fisher said it is economically lucrative for companies to share positive news about their work.
But the truth is that there will not be a commercially viable vaccine this year, and when one does become available, there will not immediately be enough for everyone, he warned. It is also unlikely that any vaccine would fully protect everyone.
Prof Ooi, who leads a team working on a vaccine, said he would be satisfied if it was 50 to 75 per cent effective. A 50 per cent efficacy means only half of the people vaccinated are actually protected, and the rest could still become infected. Still, it would offer a sufficient level of protection, he said.
"Even a natural infection would not give you 100 per cent protection from a second infection," he noted.
Vaccines generally work better in young healthy people, and less well in those who are older or have underlying medical conditions, but this may be good enough.
Prof Ooi said: "If the young people are solidly immune, they would not pass the virus on to older people, even if (older people) are not immune or not vaccinated."
Prof Fisher said having a vaccine does not spell the end of the Covid-19 pandemic. "Even after the vaccine comes, we're still going to have cases. We're still going to have little clusters. It'll just be a lot easier to manage with the vaccine."
It is also important to be able to treat patients, so most do not get severely ill or die, the panel noted.
Professor Teo Yik Ying, dean of the NUS Saw Swee Hock School of Public Health, said the economic impact of the pandemic would be harder on some segments of the population.
He said: "There will be some sectors that are being forcefully kept shut to allow the rest of the economy to function as per normal.
"How do you explain this to people: that you have to lose your job so this other group of people can continue working and earning a living? Countries will have to put in place the necessary safeguards to maintain social cohesion."
