Vice President M Venkaiah Naidu on Saturday said while vaccines do offer hope of shielding people from Covid-19. Also he pointed out that determined efforts are needed to bring the country's economic growth back on track. Naidu was speaking at Goa Legislators' Day event in Porvorim. The Vice President said: India and the world are passing through difficult times with the Covid-19 pandemic compounding the situation caused by the economic slide that was unfolding even earlier.