Singapore's vaccination strategy has worked on the principle of a phased roll-out for all Singaporeans and long-term residents to receive the maximum protection in the form of two shots delivered three to four weeks apart. The approach has now been tweaked so the maximum number of people can get good protection by scheduling the vaccine's second dose six to eight weeks after the first. The extended gap accelerates the opportunity for those waiting for the first dose, and thus extends the protective cover of inoculation faster over the population at large.
With the longer interval between doses, another 300,000 people can get their first dose this month, with 4.7 million, or almost all those eligible, getting at least one dose by August. The programme will be able to reach 4.3 million individuals by the end of July. Without the shift, that figure would have been 3.9 million. So far, 1.4 million people have received both doses. Another 600,000 have had one dose, and they will get their second dose as scheduled. However, those who have booked their second dose slots can also volunteer to push back their appointments to allow for someone else to get the first dose.
The key factor is a medical one. The authorities have been at pains to point out that stretching the gap between the two doses will not affect the overall immune response materially so long as the second dose is given eventually. This is because the first dose of the mRNA vaccines used here gives about 75 per cent protection 12 days after it is injected. The degree of protection goes up to about 95 per cent with the second dose. While the difference of 20 percentage points is important, the remarkable boosting of immunity levels following the first dose does create time in which others can receive it without damaging the medical integrity of the vaccination process.
Singaporeans can rest assured that the inoculation programme continues to work in favour of all of them. What matters is how to distribute the vaccine more equitably among the population so that the whole country is better equipped to emerge from the coronavirus pandemic. This fine-tuning of the vaccination drive is necessitated by the downturn in the global situation and its inevitable effects on Singapore. New strains of Covid-19 have emerged elsewhere and entered Singapore in spite of calibrated efforts to open up the economy without exposing society to a raging pandemic. To shut borders completely would be the wrong move for a country starved of natural resources. Yet to continue as usual in the face of heightened dangers from elsewhere would be equally culpable. In seeking to balance staying open to the world and safety within, Singapore needs to refine its anti-Covid-19 policies continuously. The extent and speed of vaccination hold the key to those policies at the moment.
