For the final instalment of this series we are turning over the programme to you, our listeners. Over the past four months we’ve asked you to send us your questions, and you have obliged. But we haven’t always managed to reciprocate by answering them. In this episode, Tim Harford talks with a panel of experts who will try to answer as many questions as we can fit into a half an hour. Guests include Professor Beate Kampmann from the London School of Hygiene and Tropical Medicine, Professor Melinda Mills of Oxford University, and the GP Dr Helen Salisbury.

Way back in the distant past that was last November, we rushed to produce the first episode of How To Vaccinate The World. Those were heady days. Pfizer and BioNTech seemed to be able to produce a stunningly effective vaccine using a brand new technology faster than we could learn how to pronounce BioNTech.

Producers: Sandra Kanthal and Beth Sagar-Fenton

Listener questions can be sent to: [email protected]

Tim Harford is an economist not an immunologist, so he's on solid ground with this week’s programme which is all about numbers. Some of them are small but significant: 7 reported cases of cerebral venous thrombosis in Germany. Others are huge: 400 million doses of Covid 19 vaccine administered around the world.

Producers: Sandra Kanthal and Beth Sagar-Fenton

Listener questions can be sent to: [email protected]

More than 300 million doses of Covid 19 vaccines have been administered - that’s nearly three times the number of official Covid cases. But, the novelist William Gibson once said: the future is already here, it’s just not very evenly distributed and that’s certainly true for Covid 19 vaccines. Some countries are the haves, and others the have nots. So, where do we go from here if we are going to bring this pandemic to an end? That's the question Tim Harford asks this week's panel of guests: Gian Gandhi of UNICEF, Hannah Kuchler from the Financial Times and Prashant Yadav from Center for Global Development.

Listener questions can be sent to: [email protected]

In the UK alone, more than 20 million people have had a first dose of a Covid 19 vaccine, and the government hopes to speed up the roll out by offering every adult a first dose by the end of July. But the word “offering” may be doing a lot of work in that sentence. Not everyone is taking up that offer - and there is a lot of talk about lower take-up rates of people in who are not both British and white - sometimes lumped together with the acronym BAME - Black, Asian and Minority Ethnic.

Producers: Sandra Kanthal and Beth Sagar- Fenton

Listener questions can be sent to: [email protected]

What Are Vaccines and Why Do They Work? Produced by Hip Hop Public Health

Monopoly is a good parallel for life in a pandemic because it deals out suffering at random, and it seems to go on forever. So people can be forgiven for asking: where’s our Get Out of Jail Free card? The answer might be vaccination passports. Or, it might not; the possibility of unintended consequences looms large. This week on How To vaccinate The World, Tim Harford will be asking if we need or want vaccine passports, and what problems they are trying to solve with his guests: Simon Calder, Travel Editor of The Independent, Professor Carsten Maple of the University of Warwick and Professor Melinda Mills of Oxford University.

Vaccines and Variants is a great title for a fun new geeky game but a very bad combination for public health. New variants of the virus which causes Covid 19 are turning up in countries all over the world. Can the vaccines we have keep up with them, or do years of booster jabs await us? Tim Harford answers these questions with this week's panel of guests: Professor Peter Hotez of the Baylor College of Medicine, Professor Emma Thomson of the University of Glasgow and Dr Adam Kucharski of the London School of Hygiene and Tropical Medicine.

Listener questions can be sent to: [email protected]

More than a 100 million people around the world have received a jab for Covid 19. But, we’re greedy - we want more. The virus is mutating, so vaccinations need to happen faster. And our vaccines are good, but will have to get better. Economists like to talk about incentives to get products to market faster, but will these tools that will work for the development of vaccines? This week Tim Harford puts this question to Professor Michael Kremer, winner of the Nobel Memorial Prize in Economics,

Producers: Sandra Kanthal and Josephine Casserly

Listener Questions can be sent to: [email protected]

This week's panel of guests include President Biden’s Chief Medical Adviser, the long-serving director of the Infectious Disease Institute at the US National Institutes of Health, and a doctor who has been played on screen by Brad Pitt. All three of them are, of course, Dr Anthony Fauci. In this episode of How To Vaccinate The World Tim Harford talks with the world famous immunologist about the effectiveness and the roll out of vaccines in the US and around the world, what it’s been like to share a stage with Donald Trump in the depths of a pandemic, and answers questions from some of our loyal listeners.

Listeners questions can be sent to [email protected]

No one’s safe until everyone is safe - it’s a phrase we are getting used to hearing. We are all going to look after each other and make sure everyone gets the vaccines they need. But this noble sentiment seems to be buckling under first contact with political reality, as rich countries jockey for position at the front of a very long queue. The elbows are out - just ask AstraZeneca. In this episode of How To Vaccinate the World, Tim Harford and a panel of expert guests, have a lively discussion about the dangers and perhaps the advantages of vaccine nationalism.

Producers: Sandra Kanthal and Josephine Casserly

Listeners questions can be emailed to [email protected]