More or Less

Cases of Covid 19 began to soar in the US in the autumn. By early January there were around 300,000 new cases a day. But since then the numbers have fallen steeply. What caused this dramatic drop? From herd immunity to the weather, Tim Harford explores some of the theories with Derek Thompson of The Atlantic magazine and Professor Jennifer Dowd, deputy director of the Lever Hume Centre for Demographic Science at the University of Oxford.

Are different countries counting deaths from Covid 19 in the same way? Tim Harford finds out if we can trust international comparisons with the data available.

We discover Peru currently has the most excess deaths per capita over the course of the pandemic, while Belgium has the highest Covid death count per capita.

Tim speaks to Hannah Ritchie from Our World in Data and John Burn Murdoch, senior data visualisation journalist at the Financial Times.

The UK was the first European country to surpass 100,000 deaths from Covid 19. The UK has one of the worst death rates. But can we trust the numbers? Many of our listeners have asked us to investigate.

If we brought all the virus particles of the Sars-CoV-2 virus from every human currently infected, how much would there be? This was a question posed by one of our listeners. We lined up two experts to try to work this out. YouTube maths nerd Matt Parker and Kit Yates, senior lecturer in mathematical biology at the University of Bath, UK give us their best estimates. One believes the particles would fit into a small can of coke, the other a spoonful.

Are exports to the EU from the UK down 68% since Brexit? This apocalyptic statistic is being widely reported, but does it really tell us what’s happening at Dover and Folkstone?

Ministers are tweeting reassuring numbers about flammable cladding on high rise buildings. We’re not so sure.

Is it really true that one in five people are disabled?

Plus, if you assembled all the coronavirus particles in the world into a pile - how big would it be?

Tim explores a shocking claim that life expectancy in some parts of Glasgow is less than it is in Rwanda. But is that fair on Glasgow and for that matter is it fair on Rwanda? And a listener asks whether loss of smell is a strong enough symptom of Covid that it might be used to help diagnose the virus, replacing rapid testing.

Presenter: Tim Harford

(Left: Rwanda refugee - photo Reza. Right: Glasgow homeless man - photo Christopher Furlong / both Getty images)

Prominent Labour politicians have claimed teachers are more likely to catch Covid-19, is that true?

England’s Test and Trace programme has been widely criticised, has it raised its game in recent months? A ferocious row has broken out between scientists about how effective fast turnaround Lateral Flow tests are, and how they should be used. We examine the data.

Plus, we examine a claim from Extinction Rebellion that British butterflies have declined by 50% since 1976.

A ferocious row has broken out among scientists about new coronavirus tests. Lateral flow tests provide results within minutes and some scientists believe they are offer accurate enough results at a speed that could allow us to resume business as usual. Others think they are so poor at detecting the virus that they could pose a huge danger.

In this week’s More or Less, Tim Harford looks at the evidence and what we know about these new tests.

Since the start of the pandemic there have been many warnings that people might die not just from the coronavirus itself, but also if they didn’t seek medical help out of fear that hospitals might be dangerous. Is there any evidence that this has happened? David Spiegelhalter is on the case.

The UK is in lockdown, but tens of thousands of people a day are still testing positive for Coronavirus. Where are they catching it? Grim data on drug deaths in Scotland has been called into question on social media. We ferret out the truth. Plus, what can venomous snakes tell us about the government's plan to increase the number of people self-isolating?

Since the start of the pandemic there have been many warnings that people might die not just from the coronavirus itself, but also if they didn’t seek medical help out of fear that hospitals might be dangerous. Is there any evidence that this has happened? David Spiegelhalter is on the case.

The UK is in lockdown, but tens of thousands of people a day are still testing positive for Coronavirus. Where are they catching it? Grim data on drug deaths in Scotland has been called into question on social media. We ferret out the truth. Plus, what can venomous snakes tell us about the government's plan to increase the number of people self-isolating?