The Indian Council of Medical Research (ICMR) Director General Dr Balram Bhargava on Tuesday said the efficacy of the Covid-19 vaccine in India is likely to remain between 50 to 100 per cent, however, they are trying for 100 per cent efficiency. “We are aiming for 100 per cent efficacy but may land between 50 to 100 per cent. However, it still would be an effective vaccine against the virus,” he said.