Are Coronavirus Lockdowns Working?
(Neil’s Note: This was a blog comment I made in response to Christopher Monckton’s article “Are Lockdowns Working?” at https://wattsupwiththat.com/2020/04/04/are-lockdowns-working/#comment-2956309, about the efficacy of lockdowns at lowering the rate of spread of the currently raging coronavirus epidemic. I made some further comments in replies, too).
The former mathematician in me decided it was about time to use the data we have to make a direct assessment of Christopher Monckton’s hypothesis that the lockdowns are working.
What I did was look, not at comparisons between countries, but at the graphs of total cases and daily new cases which are readily available on worldometers.info. As long as the reporting of cases within a country is done in the same way each day, I should be able to make reasonably reliable comparisons between the numbers of cases in a country at different stages of the epidemic. I simply picked the top 12 European countries in terms of total number of cases, and looked at the graphs for each.
First up was Spain. Something interesting jumped right out of the paper at me when I looked at the total cases graph. The curve comes in two parts; an exponential part, followed by a pretty much linear part. The transition in Spain was quite sharp, around March 24th. The daily new cases graph shows it, too; new cases were increasing exponentially up to about that date, and since then have been increasing far less, or even static. The Spaniards seem to have brought in their lockdown very quickly on March 13th and 14th, so the change in the regime came about 10 days after lockdown. Not at all far from the incubation period of the virus, of which the best estimate I have heard is 6 to 14 days.
Next, Italy. Here, you see the same thing. An exponential phase, followed by a linear phase. The transition came somewhere around the peak of March 20th. When did the Italians go into full lockdown? March 8th, says Wikipedia. 12 days.
You can also see a wobble in the total cases line since 20th March. This shows up as an oscillation in the daily new cases, with a period which looks to be around 5 to 6 days. And the Italian daily cases now look as if they’re on a downward trend. Furthermore, you can see a similar wobble in the data before 20th March – there are often peaks 5 or 6 days apart. I don’t know what it is about the virus that causes this effect, but I’m not an epidemiologist.
Looking again more closely at the Spanish data, you can see the wobble there too, though it’s easier to see if you look at the minima rather than the maxima.
To Germany. Again, an exponential part followed by a linear part with a wobble. The wobble seems to have a bit longer period here, 6 to 7 days. The peak day so far was March 27th, only 5 days after Germany went into full lockdown. But equally, the effect may have come near the mid-point of the cycle. It’s not yet clear whether the overall trend in new cases in Germany now is up as in Spain, or down as in Italy. Time will tell.
The French problems with nursing home deaths data seem also to have applied to case data from those sources, so I’ll skip France.
UK data is inconclusive, but you surely can see that wobble between March 27th and April 1st! We’ll have to wait another week to see on this one. My best guess is a graph similar to Germany’s, with the transition to linear coming in the middle of the next cycle, since full lockdown began on March 24th.
Switzerland follows the Italian model of peaking, then starting to go down gradually. The wobble is a lot less obvious here. The peak on March 20th was only 4 days after the Swiss went into full lockdown, but they did start a partial lockdown on February 28th, and the Swiss are very law-abiding people.
Belgium started lockdown on March 18th, and the transition to linear may well have come around March 28th. Again, time will tell.
The Netherlands has a similar pattern to Spain, though with far less cases per million.
Austria looks to be the country which is ahead of the game – there is a clear flattening out of the total cases curve, and a very significant drop in daily new cases since that mighty peak on March 26th. I suspect the peak is higher than it ought to be because of late reporting of cases which actually happened on March 25th; but they went into lockdown on March 16th, which is… 10 days before the peak.
Portugal is another inconclusive one, like the UK. If that big bar on March 31st does turn out to have been the peak, it will have been 12 days after start of lockdown.
Sweden… ah, Sweden. This is the one which, I expect, will prove the matter one way or another. Looking at the total cases graph, what I see is not an exponential followed by a linear part with wobbles, but an exponential with wobbles. Yesterday’s low number notwithstanding, I don’t see anything in the daily cases yet to suggest any transition to linearity. And the Swedish semi-lockdown began on March 17th. If the Swedes are in big trouble at the top of the next wobble cycle, probably around April 8th, we’ll have some good evidence to support Christopher Monckton’s contention that the hard lockdowns are working.
Lastly, Norway is a really odd one. That March 27th figure looks suspicious to me; unless the wobble has a far longer period in Norway than anywhere else. Moreover, if there has been a transition to linear, it seems to have happened on March 12th – the precise day they locked down!
All in all, I think the prognosis is quite good for Christopher Monckton’s hypothesis that the lockdowns are working; but maybe not so good for our Swedish friends.