Covid: How do you vaccinate a billion people?

When it comes to vaccine making, India is a powerhouse.

It runs a massive immunisation programme, makes 60% of the world's vaccines and is home to half a dozen major manufacturers, including Serum Institute of India - the largest in the world.

Not surprisingly, there's no lack of ambition when it comes to vaccinating a billion people against Covid-19. India plans to receive and utilise some 500 million doses of vaccines against the disease and immunise up to 250 million people by July next year.

This confidence is bolstered by...