Bill and Melinda Gates Foundation said on Thursday it had pledged $250 million in additional funding towards the global campaign to fight the coronavirus pandemic.Part of the funds will be channelled to the distribution of life-saving doses of Covid-19 vaccines to parts of Sub-Saharan Africa and South Asia."We have new drugs and more potential vaccines than we could have expected at the start of the year," said Bill Gates in a statement."But these innovations will only save lives if they get out into the world," he said.Funding is one of the biggest hurdles for Africa, home to some of the world's poorest countries.The World Health Organization has identified the goal of vaccinating 3% of Africans by March 2021 and 20% by the end of next.