Adar Poonawalla, the chief of Covishield manufacturer Serum Institute of India, today said the billionth dose of coronavirus vaccine is a milestone for India and over the next two months, the country will catch up further. There is even a possibility of a booster shot early next year for those who need it -- there will be enough doses, he added. Mr Poonawalla, however, said "ethically and humanely, our outlook will be to vaccinate the world, especially Africa, with both doses of the vaccine first".