Booster shot can increase your immunity by up to 200 times: expert virologist
People who have received two vaccine doses against Covid-19 can benefit by getting a third jab, or booster shot, which will significantly boost their immunity against the coronavirus, Chulalongkorn University expert virologist Dr Yong Poovorawan said on Tuesday.
During the virtual seminar “Covid-19 Vaccine Quarterly Outlook”, Yong said using inactivated vaccines (for example Sinovac) as a booster can increase recipients’ immunity by up to 10 times, while a viral vector vaccine such as AstraZeneca will increase immunity by up to 100 times.
“Meanwhile, mRNA vaccines such as Pfizer and Moderna can boost recipients’ immunity against Covid-19 by up to 200 times,” he said.
“However, a study in Israel found that the immunity of mRNA recipients decreased at a faster rate than that of viral vector vaccine recipients, and can last for about three months,” Yong said. “The country is therefore considering giving a fourth jab to people in high-risk groups to keep their immunity at a high level.”
Yong also said the optimal interval between 2nd and 3rd shots should be from three to six months, but recipients who carry a high risk of contracting Covid-19, like medical professionals, should get a booster jab as soon as they hit the three-month mark after the second jab.
Yong estimated that the Omicron variant would replace Delta in the next 1-2 months in Thailand due to its faster rate of spread.
“Many studies have found that two doses of any vaccine are still not enough to prevent the Omicron variant, therefore everyone should get a booster shot as soon as they can to reduce the risk of developing severe symptoms and death,” he suggested.