Here's some good news for a change. A year ago, the UK hosted a vaccines summit in London where donor countries were asked to pledge money for mass immunisation programmes.

Against a backdrop of a global economic crisis that has led to belt-tightening in the west, the summit exceeded expectations and raised $4bn (£2.57bn) in four hours.

It is, of course, one thing to secure promises of financial assistance from cash-strapped rich countries, quite another to ensure that they hand over the cash. Many western countries have form when it comes to talking big at summits and then quietly forgetting about their commitments once they get back home.

This time, according to Save the Children, they have ponied up in full. Not a single donor has reneged.

But has the money actually been spent well? This is the point made by critics of aid, who say that all too often development assistance represents poor value for money and can do more than harm than good.

Not the case this time, according to STC's Justin Forsyth. "We estimate money already disbursed by donors will immunize 62 million children, averting nearly 1 million future deaths. This means that more children than ever before in history have received new life-saving vaccines against two of the world's biggest killers, pneumonia and diarrhoea."

The Save the Children report can be found here.