My grandfather worked on the bomb that was dropped on Hiroshima, and it troubles me.

It also troubled some of the scientists who developed it.

Find out more in the bomb, a brand new podcast from the BBC World Service, available now.

You are listening to the documentary, Part 2 of Vaccines, Money and Politics on the BBC World Service.

I'm Sandra Cantol.

People have been asking for the vaccine when is a vaccine coming. In fact even when some of the

restrictions started loosening quite a number of people, as well as the vaccine was in as we know there's no vaccine at the moment but there's hope.

Hope it's what we all need a bit of at the moment, a hope that one day there'll be an end in sight to the pandemic of 2020.

This hope rests largely on the shoulders of scientists, working around the world at a pace and scale

we've never seen before. The world first heard about a novel virus, SARS COV2, in January of this year.

Since then, it's infected tens of millions of people worldwide,

and the disease it causes, COVID-19, has killed over 700,000.

Until a vaccine is found to break this chain of transmission, much of what you and I considered normal life will remain on hold.

That's why there are more than 150 projects underway all over the world to safely develop at least one vaccine

for COVID-19 in the incredibly ambitious time frame of 12 to 18 months.

Dr. Francis Dien Wantsa is an immunization manager for the Ministry of Health and Zambia. And like public health officials around the world, he's

waiting for the day he'll be asked to roll out the new vaccine. But it's hard to plan for

something unknown. The vaccine itself is going to be injectable or almost like injectable, how many doses and so on.

So plenty of questions and answers.

The beauty though is that we've done something similar before. So we kind of have

a blueprint. In the first part of the series we heard about how complicated it will be to

discover and produce a vaccine.

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