People will continue to need vaccine jabs for long-term high immunity: Dr Yong

He stressed that Covid-19 vaccines can reduce the severity but cannot prevent infection due to the virus’s short incubation period and mutation.

Yong pointed out that using new Covid-19 variants to produce vaccines would not help improve efficiency.

He went on to write that immunity from Covid-19 is “not very high”, while vaccines cannot prevent infection even though they provide high immunity, but this would eventually decrease as time passed.

“Whatever the vaccine, its maximum efficiency is 14 to 28 days after vaccination and this will eventually decline,” he warned, adding that there is no such thing as “the best vaccine”.

Yong said people can be infected with Omicron easily, but they will develop mild symptoms if they are fully vaccinated or have been infected with other variants before.

However, he pointed out that people who were infected with Omicron could spread the virus, adding that children were among new Covid-19 cases even though they were vaccinated.

Yong stressed that children will have to go to school.

“Schools in many countries including Singapore have not closed but are conducting antigen tests on students. Those who test positive are ordered to isolate at home for seven days. They can then return to school without taking any more tests as the chance is low that they will spread the virus seven days after infection,” he explained.

Yong said he would continue to recommend “stimulating immunity” with vaccines even if people have received the third and fourth jabs.

He made it clear that receiving the third jab is necessary to reduce the severity of the disease and enable the body to become “familiar” with the virus.

“The important thing right now is protecting vulnerable people, while everyone must take care of their health and undergo prevention measures in this new normal era,” he wrote.

Life “must move forward”, he added.