Loading the player... South African variant could significantly reduce vaccine protection, says Pfizer A laboratory study suggests that the South African variant of the coronavirus may reduce antibody protection from the Pfizer-BioNTech vaccine by two-thirds, and it is not clear if the shot will be effective against the mutation, the companies said on Wednesday. Companies are making investments and talking to regulators about developing an updated version of their mRNA vaccine or a booster shot, if needed. COVID-19 vaccine likely to be available in open market after 'prime targets' covered: Guleria The COVID-19 vaccine is likely to be available in open market only after the 'prime targets' are vaccinated and there is an equivalence of supply and demand, All India Institute of Medical Sciences (AIIMS) Director Randeep Guleria said on Wednesday. India began its vaccination programme against COVID-19 on January 16. Healthcare workers and frontline workers are to be vaccinated first, followed by people aged above 50 years in third phase, which is likely to begin in March.