Serum Institute of India's CEO Adar Poonawalla has warned there won’t be enough Covid-19 vaccines available in the world till 2024 at the earliest, according to a media report on Monday.“It’s going to take four to five years until everyone gets the vaccine on this planet," said Poonawalla to Financial Times.The CEO of the world’s largest vaccine manufacturer has estimated that if the Covid-19 shot is a two-dose vaccine — such as measles or rotavirus — the world will need 15 billion doses, reported FT.The Pune-based pharma giant has partnered with five international pharmaceutical firms, including AstraZeneca and Novavax, to develop a Covid-19 vaccine and committed to producing one billion doses, of which it has pledged half to India..