You're listening to a podcast from the BBC World Service.

This is Hard Talk with me, Stephen Sacker.

Thanks for downloading this edition of the program.

I do hope you enjoy it.

Welcome to Hard Talk on the BBC World Service.

I'm Stephen Sacker.

My guest today has, for the past year, been at the forefront of the global scientific effort to get on top of

the COVID-19 pandemic. Sumya Swaminathan is chief scientist at the World Health Organization.

She is a trained pediatrician, an experienced researcher, and former boss of the Indian Council

of Medical Research. The WHO acts as an emergency response

coordinator, a global advisory agency, and a knowledge-sharing hub. And in the past year,

it has been sorely tested. First came questions about how it handled the first evidence of a

new respiratory disease coming from

Wuhan, China. Then came criticism of its changing guidance on preventive measures, from

travel bans to face masks and lockdowns. And now the biggest questions concern the rollout of

vaccines. The richest countries are desperate to procure supplies

to quickly immunise their populations

and return to a form of normality.

But what about the billions of people in countries

unable to spend what it takes?

If the vaccination rollout is patchy and slow,

will the virus have time to mutate and undermine the containment effort?

...