The government will carry out a two-dose policy under the National Covid-19 Immunisation Programme although a study had shown that a single dose of the Pfizer-BioNTech vaccines had up to 85 efficacy against the virus, says Khairy Jamaluddin..br br The Science, Technology and Innovation Minister said that at a press conference in KLIA following the arrival of the first batch of Pfizer-BioNTech vaccines on Sunday (Feb 21), adding that the vaccination programme would be voluntary as the government had decided not to make it compulsory.br br The government will also introduce a scheme to ensure that those with serious side effects from the vaccination receive ex-gratia payments.