Coronavirus: should we panic?
FT data journalists John Burn-Murdoch and Federica Cocco look at what four key charts tell us about the spread of Covid-19
Produced and edited by Joe Sinclair; studio filming by Nicola Stansfield and Petros Gioumpasis
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So coronavirus is a massive story. Should we be panicking?
Let's look at the data. Today we're going to talk through four charts showing how coronavirus compares to different diseases on all sorts of measures. And yeah, how dangerous is it for you?
Let's have a look, first, at the number of cases that we've seen, starting from day one of the epidemic, or when China first reported it to the World Health Organisation. And let's compare it to the last famous epidemic, Sars. The number of Sars cases stayed kind of low, and then stabilised at around 10,000.
So after about 176 days, just under 10,000. And again, like you said, everyone was panicked about Sars.
And rightly so, because it had a very high fatality rate.
It did. And then, let's look at how coronavirus, Covid-19, compares to that. So again, we start from the first recognised case.
So I can see from this there is cause for concern.
Yes. That's well over 60,000 after 60, 70 days, compared to under 10,000 after 176.
Yeah. I counter to this, that still, the number of deaths is very low, especially compared to Sars. We're looking at a mortality rate of around 2 per cent. It's more in a range, but it's still at around 1,500, around that. So it's very, very low.
OK, so you're saying, yes, the cases line may look scary but the deaths line is not anything to be too worried about.
Yeah. I mean, by comparison, for example, it's estimated that around 60,000 people die from seasonal flu in the US alone, every year.
So far, it looks like it's remained fairly contained. Here we have the Hubei province. It is the epicentre. It is where the epidemic first started. It spread around China. But as we get further and further from Hubei, then we see fewer cases.
And I guess that's because the Chinese government immediately enforced a lot of quarantines and that kind of thing. And there was a lot of travel restrictions.
Now, there have been, obviously, some cases in other countries. But as we can see here on one of our own graphics...
The vast majority have remained in China.
And again, you see that the localisation factor. China is more connected to its immediate partners. So there are a few more cases in places like Japan and the rest of Asia than there are in the rest of the world. However, people, as you've looked at, have died outside of China.
We've just had three deaths outside of China. If we compare that, for example, to the Spanish flu, when we were seeing just a fraction of the global mobility that we have today, then during that period in 1918 we saw more deaths than in World War I and World War II combined.
So I think that those numbers really put it into context. Of course, that was before vaccines.
But I guess the other thing, though, is that you had millions of people moving around the world because of the war. And that was sort of spread. Whereas today, they've been able to really lock down.
Yes. In this case, it's interesting. It spread more during business conferences. And so possibly as a result, we saw that middle-aged men seemed to be more vulnerable to this particular virus, which is interesting.
But let's look at the deaths outside of China. OK, so three weeks after the epidemic started, we had just four cases reported outside of China. Now we're in mid-Feb, we're looking at just under 1,000. And they have been all over, around 20 countries in the space of... how long has it been?
In just a couple of months. And again, we're looking at just the cases outside of China now.
Yeah, yeah, forgetting China for a second. Within this space, now we're in mid-February, we have only seen, so far, three deaths. We're going to pin them in yellow. One's in on Hong Kong. One was in Japan, an 80-year-old woman. And one was in the Philippines.
The fatality rate is still very low. And really, the numbers say that it's not as concerning and as fatal as other epidemics, including the seasonal flu that we see every year.
It's how infectious it is. That, I think, is really what we should still be focusing on here.
Should we have a look at that?
Let's compare seasonal flu to coronavirus.
In terms of the infection rate?
Exactly. And let's start with two hypothetical families of five. This is my family with seasonal flu.
And here's my family with the current Covid-19 strain of coronavirus.
So how many people do they infect?
Now we're seeing what happens in those first few days, as these people go out, they mingle, they mix. And that infection gets spread. And as you can see, it's spreading markedly faster for the people who've got coronavirus than it is for people with seasonal flu.
As we go through to a second cycle, you see this even more. So seasonal flu is essentially about the same number of people again, who have been infected. Whereas in coronavirus, instead of having just another 12 infected, it's now another 34. So it spreads far more rapidly, even though those two numbers - 2.6 and 1.3 - that we started with were not too distant.
And this is what is known as the R-value, how many people are infected by another person. If it's below 1, then it's not contagious at all.
What I can see here is that the speed of contagion for coronavirus does, in fact, look pretty terrifying. But how does it compare with the fatality rate?
That is the question. And how does it compare with many other viruses, as well? So let's take a look at that.
OK, so what we were looking at there was the difference, along this horizontal axis, in infection rate.
The sort of R-value, how contagious something is.
Exactly. That's the number we have on the horizontal axis here, of how infectious different diseases are.
You can see measles is pretty infectious.
So is polio.
Polio is relatively infectious. The current strain of coronavirus is down here at about 2.6. The common cold, seasonal flu, less infectious.
But the other really important thing, as you've mentioned, to take into account here is the mortality rate. Once you've got this virus, what are your chances of surviving? What are your chances of dying? And that's what we have...
Two very famous epidemics, bird flu and Ebola. Basically, if we were in a pandemic, we'd be in the region of here.
What we're saying is, as you move further in this direction a disease is more infectious. And as you move further up...
It's more deadly.
With coronavirus, there is still some uncertainty. We are in the early days. So let's say it's more or less in this shade. But it is a range.
It's a range. And one of the reasons for that uncertainty is because of how China has been reporting the cases.
Yes. Initially, to try and sort of contain, maybe, even the panic for the disease, they were under-reporting. And then there was a lot of suspicion about the figures that they were reporting because China does traditionally sort of fudge some of the figures. It's done so when it comes to economic growth, when it comes to poverty.
And we talked about the range here. The key axis here for that range actually was the vertical, or the mortality rate. And that's because, if you think about it, the mortality rate is the number of people who have a disease, a virus, who go on to die. And if either of those numbers - the number of deaths or the number of cases - is skewed, is wrong, it's going to skew the results.
So what was happening in China was because the Chinese were under-reporting the number of people with the infection at all, it actually made the mortality rates look a lot higher.
So it looked a lot more dangerous, in fact, which is kind of counterproductive.
But as soon as it spread outside of China, we saw that, as we saw earlier, there were only three deaths. The mortality rate was looking more like around 2 per cent.
Exactly. So for a while, the epidemiologists looking into this, they had numbers showing that in parts of Wuhan and Hubei province, the mortality rate was as high as 10 per cent or even 18 per cent. Whereas, as you say, once we were able to look at cases outside of China, where the data was more reliable, it was about 2 per cent.
And that's because, as soon as people moved out of China, like a British resident coming back to the UK, having been to a conference where there were reported cases of coronavirus, people like that would get examined as soon as possible. We saw a case, for example, of a super-spreader that ended up on front pages of loads of newspapers in this country, who had no symptoms. And that's why he infected 11 people. He didn't know that he should have been in quarantine.
This is also one of the reasons that people are a bit more worried about the spread of coronavirus than Sars. Because in the case of Sars, if you weren't symptomatic, you couldn't actually affect anyone else.
The mortality rate for this is pretty low. But it's the fact that it can spread easily and without people even knowing they're ill, that is why maybe people are panicking.
I think I'll be following this story closely, not because I'm now in the panic zone. I'm firmly still in the no-panic zone. But I think it's leading to a lot of interesting shifts in the relationship between Chinese society and government that might turn into a different story altogether, where we're seeing a sort of break in trust between the Chinese government and Chinese society. So for me, I'll be following this closely, but maybe for slightly different reasons so far.
That's very FT of you!