Get your third jab for extra protection, urges virologist
In a Facebook post on Thursday, expert virologist Dr Yong Poovorawan said people need at least three doses of the Covid-19 vaccine to protect themselves from the Omicron variant.
He said the booster dose should be AstraZeneca or the mRNA Pfizer or Moderna vaccines, as they will increase people’s immunity, especially if they have had two jabs of the inactivated Sinovac or Sinopharm vaccines.
He added that people who have received two Sinovac shots and followed up with an AstraZeneca, Pfizer or Moderna booster will have the same immunity as people who have received two jabs of AstraZeneca and then a third shot of either Pfizer or Moderna.
He added that even half a dose of Moderna provides enough immunity.
However, the virologist said this was a basic study and that we need to wait for the results of a study into neutralising antibodies that work against Omicron and Delta.
Yong added that people in the US and UK were being given half a dose of Moderna if their first two doses were AstraZeneca.
He added that the results of a study into the booster dose for people who received a combination of Sinovac and AstraZeneca will be available next year.
These studies are necessary to work out which vaccine formula is most effective, he added.