Achieving herd immunity via infection ‘too big a price to pay’
Achieving herd immunity to Covid-19 through natural infection in the population will lead to a higher number of deaths and infections and overwhelm Singapore's healthcare system, the Health Ministry (MOH) director of medical services Kenneth Mak said yesterday.
During a virtual briefing, Associate Professor Mak made it clear that there was "too big a price for us to pay" to reach herd immunity in this way and thus it has not been part of Singapore's strategy to fight the coronavirus pandemic.
"If we assume that we're going to let Covid-19 spread freely in our population, we will then have to accept the costs associated with more seniors getting ill, more seniors getting complications, and a significant number of seniors even dying from infection," he said.
"We will then see also high numbers of patients with Covid-19 infection potentially in our hospitals, in our ICUs, and this is a situation which is a very dangerous one."
He added that if the virus is contained well in Singapore, the country will never reach a situation where herd immunity is achieved, unless vaccination takes place.
Experts estimate 60 per cent to 80 per cent of the population needs to be infected and immune to the virus before herd immunity can be achieved, though such figures are often best guesses, said Associate Professor Vernon Lee, director of communicable diseases at MOH.
Prof Lee, who also spoke yesterday, noted countries that had high numbers of infections and conducted serological testing - which detects antibodies to determine whether a person has been infected - found the percentage of positives was "way below" the threshold needed for herd immunity.
"So to get to that kind of percentage to achieve herd immunity will require a large number of people to get infected...
"So far, I don't think there's any country in the world that has tried to use overall herd immunity as a strategy to combat Covid-19," he said.
Yesterday, MOH confirmed 884 new coronavirus cases, taking the country's total number of infections past 24,000.