Why Do Vaccine Efficacy Rates Differ?

Pharmaniaga has inked a deal with Chinese biotech firm Sinovac to fill and finish 14 million doses of Covid-19 for Malaysians. But with questions starting to emerge over the efficacy of the Sinovac vaccine, we speak to Emeritus Professor Dr P.T. Thomas, Executive Dean at the Faculty of Health and Medical Sciences, Taylor's University, to help us understand vaccine approvals and some of the data coming out of different countries.

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