Press conference at the GAVI Alliance pledging event. UK aid will help vaccinate a child in the developing world every two seconds for the next five years, the Prime Minister announced today. Over 80 million under-fives living in some of the poorest countries in the world will be vaccinated against killer diseases like pneumonia and diarrhoea with the help of British aid as part of a broader collective effort. Opening a four-hour push to save lives hosted by David Cameron, Ellen Johnson-Sirleaf (President of Liberia) and Bill Gates (Bill and Melinda Gates Foundation), the Prime Minister called on other donors to dig deep in order to reach the target of vaccinating at least a quarter of a billion children in the next five years in order to save the lives of four million children.