Adar Poonawalla, CEO of the world's largest vaccine manufacturer Serum Institute of India, today said trials in India have started for Covovax - the coronavirus vaccine being developed in partnership with American vaccine developer Novavax. Mr Poonawalla, who had earlier hoped to launch Covovax by June, this afternoon tweeted that it is likely to be launched by September. The Covid jab - found to be 89.3 per cent effective in a UK trial - has been tested against African and UK variants, believed to be much more infections.