Different Booster Shots The Way Forward?

Canada, Spain, UAE and several countries are now offering Pfizer or Moderna vaccines as a booster to AstraZeneca. Russia and China, too, are looking at a mix and match of other vaccines. Russia, for instance, has been planning on testing a combination of the AstraZeneca and Sputnik V vaccines - which could be interesting for India. NDTV speaks to experts on whether this could lead to better immune response and solve delays due to vaccine supply shortage.