Thursday 3 December 2020

COVID-19: the “second wave” in Europe


A month ago, I compared the histories of the COVID-19 epidemic in fourteen Western European countries. At that point, the “second wave” of the virus, which had been building throughout the region for three or four months, was giving governments an excuse to start re-introducing lockdowns. So, I said that I would review the situation in a month or so. That month has now elapsed, so here’s the review. Maybe, just maybe, I’ll now have enough data to form some idea of which lockdown measures have been effective, and which haven’t.

Once again, here is the list of countries:

Austria

Belgium

Denmark

France

Germany

Ireland

Italy

Luxembourg

Netherlands

Portugal

Spain

Sweden

Switzerland

UK

The data sources are the same as before: Our World in Data and the Blavatnik School of Government, both at Oxford University. The data I used was taken on December 3rd, and it included figures up to and including December 2nd.

In the last week or so, the Our World in Data feed has changed quite substantially. Most data before the third week of January has been deleted. Some countries – France, Germany and Sweden at least – have taken the opportunity to wipe and re-write a lot of their data, some of it right back to the beginning of the epidemic. And the data for UK dependencies (Jersey, Guernsey, Isle of Man, Gibraltar) and Danish dependencies (Faeroe Islands, Greenland) has disappeared entirely. I would have expected that this data might have been consolidated into the parent country’s; but for the UK at least, I don’t see any evidence of this.

Every so often, the Our World in Data feed adds new data columns. One of these recently added is the reproduction rate (Rt). This is the average number of new infections passed on (as at a given day) by a single infected person. It is usually expressed as a fraction. Rt bigger than 1 means the infection numbers are generally rising, and less than 1 means they are generally falling. In the UK at least, this is modelled data rather than measured data. And, as we’ll see, some countries’ figures are smoother than others, so it looks as if different countries are calculating it differently. But it’s still of interest to compare even a modelled Rt with the observed rate of growth of new cases.

Also, in November the Swedes have also completely re-written their lockdown stringency data, and it now looks as if for months their lockdown hasn’t been nearly as light as we had been led to believe. All this said, I’ll repeat what I’ve said many times before; It’s the best data I have, so I’ll use it.

Cases

I’ll begin with cases. Here are the total (cumulative) cases per million population over the whole period of the epidemic, up to December 2nd.


Here is a daily cases per million population comparison. The data shown are centrally averaged over a 7-day period. That is, the date against which a count is plotted is the 4th (central) day of the period.


In the great majority of the 14 countries, the new case counts have peaked since late October, and in many have since fallen significantly. So, the recent lockdowns must have had an effect. Which measures have had the most effect, is a moot point at this stage.

Here is the list of daily cases per million as at the end of the month:


To put this in perspective, only Spain, Ireland and France are currently below the 200 new cases per million population per day, at which the WHO considers the virus to be endemic, and no unlocks should be considered. However, four more countries, including the UK, are now only slightly above it.

Another way to look at the cases figures is in terms of weekly new case growth. This is the percentage growth in the (weekly averaged) new cases from a particular day to the same day of the week a week later. This requires the weekly averaged new cases up to 3 days after the current date, meaning there must be at least 6 days of case data after the current date. That is why the graph stops before the end of November.


It’s obvious that, over the last four weeks, the trends in weekly case growth have almost all been downward. So much so, that only three of the countries are now showing positive growth in new cases:


Another way to look at infection rates is to plot the reproduction rate, Rt. This is based on numbers of infections, not cases, so it may show a slightly different picture to the weekly case growth. Later, when I come to plot the two on the same axis, it will become plain that while the two are clearly related, they don’t always move together in perfect sync.

Here are the Rt values supplied by each country over the course of the epidemic. With the exception of Sweden, the Rt rates have been trending down throughout November:



The UK is one of only four of the countries with an Rt rate below 1 at the end of November.

In contrast, the trends in lockdown stringency have almost all been upward since late October:


The UK (pink line) appears to be bucking this trend; but, like most things political, that is a deceit. The apparent drop around November 10th was caused by the release of “circuit-breaker” lockdowns in Wales and Northern Ireland. Yet people in England are (were?) far harder locked down at the end of November than at the end of October. At the moment at least, the figure pulled through to Our World in Data only reports measures which are in place UK wide; it seems to miss additional measures in the individual constituent countries. On top of the currently reported figure of about 64%, these additional measures account as of November 30th for around 5% extra stringency in England, 3% in Northern Ireland and Wales, and around 1% in Scotland.

Tests

The number of cases which get found depends, in part at least, on the testing capacity available. Here are the cumulative tests carried out per 100,000 population in each country (except Sweden and France, which do not report cumulative test counts):


Luxembourg and Denmark are well ahead of the rest. In fact, the number of tests done in Luxembourg since the start of the epidemic is more than twice the population!

Another interesting statistic is the cumulative percentage of positives among the tests done since the very beginning of the epidemic:


In many of the countries, the cases per test percentage has climbed significantly in the second wave of the epidemic. I’d guess this is simply because infections have been climbing faster than any increase in the number of tests available. This is consistent with the observation that, in most of the countries, this ratio now seems to be nearing a second peak.

Deaths

Here are four spaghetti graphs of deaths from the virus. The first is total deaths per million population. The second shows the daily deaths per million, over the course of the epidemic; and I have appended to it a histogram of the deaths per million rates as at November 30th. You can see here which countries have started to “get on top” of the second wave, and which haven’t. The third shows deaths per case, with the cases offset 21 days back from the deaths (21 days being the mean length of the course of the disease, in the UK at least). The fourth and final graph shows the cumulative totals of deaths per case over the whole course of the epidemic.






The UK (pink line) is not doing well in the deaths-per-case stakes. It is second only to Italy in current daily deaths per case. And the UK is now top of the list in terms of deaths per case over the whole epidemic, at about 3.6%. Deaths per case is, I think, a fair indicator of lack of quality in a country’s health care system; for lack of testing capacity, and less effective treatment of those who need hospitalization, will both tend to increase it.

Lockdowns

I come now to the meat of this review. For each country, I have plotted weekly case growth percentage (blue line), lockdown stringency percentage (brown line) and Rt rate multiplied by 100 to express it as a percentage (grey line), all on the same graph. Both the weekly case growth and Rt are capped at a maximum of 200%. If a particular lockdown measure is effectual, then I would expect the grey and blue lines to move in the opposite direction to the brown, at or shortly after the day the measure comes into effect. A newly introduced lockdown measure, if successful, ought to visibly slow Rt rate, or weekly case growth, or both, within the incubation period of the virus (maximum 12 days).

This is complicated by the fact that, as you will see from the graphs, the virus has a rhythm of its own. Under conditions of constant stringency, the weekly case growth tends to oscillate periodically. The period can be different in different countries, and sometimes varies from time to time within a country; but 2 to 6 weeks from peak to peak or trough to trough is typical. Left to itself, over the course of many cycles, the weekly case growth will tend to rise. But if a lockdown measure is effective, it may change the overall trend between peaks or troughs from upwards to downwards, and may also start to smooth out the peaks and troughs.

As to the reproduction rate, it too tends to oscillate periodically, in the same direction as the weekly case growth. Peaks and troughs in weekly case growth often show a few days ahead of peaks and troughs in the Rt rate. However, as some of the examples below will show, it is now quite common to have Rt above 1 and case growth negative at the same time.

The other component of my review is the detailed data, which the Blavatnik School of Government provide on the status of 12 lockdown indicators (9 of which contribute to the stringency index) for each country for each day. I have converted these to a list of measures which have been imposed (or unlocked) in each country, with dates, since August 1st. I have also included a summary of the currently active lockdown measures in each country.

Austria

Date

Stringency

Measures

20200906

36.11

Schools: Recommended closed (Regional)

International: Ban some arrivals

20200914

36.11

Face covering: Required when with others

20200917

37.04

Workplaces: Recommended closed (Regional)

Gatherings: Up to 11-100

20200929

40.74

Stay at home: Recommended

20201013

44.91

Events: Mandatory cancelled (Regional)

Gatherings: Up to <=10 (Regional)

20201017

58.8

Workplaces: Some closed (Regional)

Stay at home: Required with exceptions (Regional)

Travel: Mandatory restrictions (Regional)

20201023

60.19

Gatherings: Up to <=10

20201027

64.81

Schools: Recommended closed

Events: Mandatory cancelled

20201102

75

Schools: Some closed

Workplaces: Some closed

Public transport: Recommended closed

Stay at home: Required with exceptions

Travel: Recommended not to travel

20201117

82.41

Schools: Mandatory closed

Workplaces: Mandatory closed

Current (20201127): Schools: Mandatory closed, Workplaces: Mandatory closed, Events: Mandatory cancelled, Gatherings: Up to <=10, Public transport: Recommended closed, Stay at home: Required with exceptions, Travel: Recommended not to travel, International: Ban some arrivals, Public info: Co-ordinated, Testing: Open, Contact tracing: Comprehensive, Face covering: Required when with others.

Notes: Given the high peaks in both Rt and case growth near the end of October, I don’t think the lockdown measures introduced during September and early October had a whole lot of effect. However, the September 29th “Stay at home: Recommended” did appear to produce an all but immediate downturn in weekly case growth and in reproduction rate. The October 23rd reduced limit on the size of gatherings also seems to have had an immediate beneficial effect. The November 2nd measures also had some positive effect, though it’s not possible to tell which of them were responsible for it. The November 17th measures have continued the drop in weekly case growth, but I don’t yet have the Rt figures to cross-check with.

There’s something else curious about this graph. Look at the peaks in Rt and in the weekly case growth. They seem to be getting vertically further apart from each other. As time goes on, it looks as if it takes a higher Rt to produce a given growth in cases. I wonder, perhaps, if the proportion of infections which do not lead to confirmed cases (for example, because they are asymptomatic) is rising? If so, that’s good news.

Belgium

Date

Stringency

Measures

 

20200729

62.96

Workplaces: Mandatory closed (Regional)

Gatherings: Up to <=10

Stay at home: Required with exceptions (Regional)

20200807

59.26

Stay at home: Recommended (Regional)

20200809

64.81

Travel: Mandatory restrictions (Regional)

20200812

58.33

Workplaces: Some closed

Stay at home: Required with exceptions (Regional)

Travel: No restrictions

20200827

52.78

Stay at home: No measures

20200930

47.22

Events: Recommended cancelled

Face covering: Required in some places

 

20201001

47.22

Face covering: Required when with others

 

20201009

45.37

Workplaces: Some closed (Regional)

 

20201019

54.63

Workplaces: Some closed

Stay at home: Required with exceptions

 

20201029

56.48

Schools: Some closed (Regional)

 

20201102

65.74

Workplaces: Mandatory closed

Events: Mandatory cancelled

 

20201116

63.89

Schools: Recommended closed

 

Current (20201123): Schools: Recommended closed, Workplaces: Mandatory closed, Events: Mandatory cancelled, Gatherings: Up to <=10, Stay at home: Required with exceptions, International: Ban some arrivals, Public info: Co-ordinated, Testing: If symptoms, Contact tracing: Comprehensive, Face covering: Required when with others.

Notes: I added the July 29th measures to the list above, because they do seem to have had an immediate and significant effect. The only national measure in that group was the restriction of gathering size to 10 or below, so that may have been what “did the trick” at that stage. The precipitate fall in weekly case growth around October 22nd, and the reproduction rate a little later, looks likely to be due to the October 19th “Stay at home: Required with exceptions.” The November 2nd mandatory closure of workplaces and cancellation of events have in fact been followed by an increase in weekly case growth, though it is still (just) negative. Rt has continued to drop, but there is no “knee” to suggest that this measure on its own made a significant difference.

I will, however, note that the stringent October 1st “Face covering: Required when with others” mandate seems to have done nothing at all to prevent the huge peak in new cases in mid to late October. And it seems to have sent the reproduction rate up, not down! I think that gives us some evidence that mandating face coverings brings little or no benefits.

Denmark

Date

Stringency

Measures

20200801

50.93

Schools: Recommended closed

20200822

50.93

Face covering: Required in some places

20200909

47.69

Workplaces: Some closed (Regional)

Gatherings: Up to 11-100 (Regional)

Public info: Co-ordinated (Regional)

20200919

50.93

Workplaces: Some closed

Gatherings: Up to 11-100

20201010

41.67

Workplaces: Recommended closed

Gatherings: Up to 101-1000

Public transport: Open

Public info: Co-ordinated

Contact tracing: Limited

20201021

37.04

Schools: Open

Gatherings: Up to 11-100

Stay at home: No measures

Contact tracing: Comprehensive

20201026

39.81

Gatherings: Up to <=10

20201109

54.63

Schools: Some closed (Regional)

Stay at home: Recommended

Travel: Recommended not to travel

20201116

50

Stay at home: Recommended (Regional)

Travel: Recommended not to travel (Regional)

20201119

43.52

Schools: Recommended closed

Stay at home: No measures

Travel: No restrictions

20201123

45.37

Stay at home: Recommended (Regional)

Current (20201130): Schools: Recommended closed, Workplaces: Recommended closed, Events: Recommended cancelled, Gatherings: Up to <=10, Stay at home: Recommended (Regional), International: Ban some arrivals, Public info: Co-ordinated, Testing: Open, Contact tracing: Comprehensive, Face covering: Required in some places.

Notes: Denmark’s Rt rate looks smoother than either Austria’s or Belgium’s, and it doesn’t show all the peaks and troughs in weekly case growth. It looks as if they may be calculating it a different way from the others.

The last three troughs in Rt (the final one is only just visible) look to have all bottomed out at similar values around 120%, and all at stringency levels near 50%, too. The October 26th reduction of maximum group size, combined with the stay at home and not-to-travel recommendations in force from November 9th to 19th, have brought the Rt down somewhat, but not as much as I would have expected. They may also have contributed to the small size of the following case growth peak; but I can’t be sure. We’ll have to wait a bit longer to draw any conclusions from Denmark.

France

Date

Stringency

Measures

20200803

46.3

Face covering: Required outside the home (Regional)

20200814

48.15

Workplaces: Some closed (Regional)

20200901

46.76

Gatherings: Up to <=10 (Regional)

20200903

48.61

Schools: Some closed (Regional)

20200922

46.76

Schools: Recommended closed

20200926

49.54

Events: Mandatory cancelled (Regional)

20201010

43.98

Events: Recommended cancelled

Travel: No restrictions

20201017

49.54

Stay at home: Required with exceptions (Regional)

20201030

78.7

Schools: Some closed

Workplaces: Mandatory closed

Events: Mandatory cancelled

Gatherings: Up to <=10

Stay at home: Required with exceptions

Travel: Mandatory restrictions

20201128

75

Workplaces: Some closed

 

Current (20201128): Schools: Some closed, Workplaces: Some closed, Events: Mandatory cancelled, Gatherings: Up to <=10, Stay at home: Required with exceptions, Travel: Mandatory restrictions, International: Ban some arrivals, Public info: Co-ordinated. Testing: Open. Contact tracing: Comprehensive, Face covering: Required when with others.

Notes: To help make sense of the French data, I’ll show also the daily cases graph:


What seems to have happened is that the French waited until the last possible moment, then on October 30th threw in just about every lockdown idea they could think of, all at the same time. It seems to have “worked,” after a fashion; but it’s been almost as harsh as the first lockdown. Moreover, the French have had “Face covering: Required when with others” nationally since July 20th. So, that rush up to the peak from July to October, I think, is fairly good evidence that face mask wearing by the public doesn’t hamper the spread of the virus.

Note also that, as of mid-November and under stringent lockdown, Rt was still above 100%, and yet new cases were dropping.

Germany

Date

Stringency

Measures

20200807

59.72

Schools: Some closed (Regional)

20200808

56.94

Gatherings: Up to 11-100 (Regional)

20200824

59.72

Gatherings: Up to <=10 (Regional)

20200903

57.87

Schools: Recommended closed

20200904

49.54

Travel: No restrictions

20201001

46.76

International: Quarantine high-risk

20201015

56.02

Stay at home: Recommended

Travel: Recommended not to travel

20201022

57.87

Stay at home: Required with exceptions (Regional)

20201102

59.26

Workplaces: Some closed

Gatherings: Up to <=10

Stay at home: Recommended

20201110

62.04

International: Ban some arrivals

 

Current (20201129): Schools: Recommended closed, Workplaces: Some closed, Events: Mandatory cancelled, Gatherings: Up to <=10, Stay at home: Recommended, Travel: Recommended not to travel, International: Ban some arrivals, Public info: Co-ordinated, Testing: Open, Contact tracing: Comprehensive, Face covering: Required in some places.

Notes: German cases have recently all but stabilized. Here’s the new cases graph:


The most likely causes of this recent stabilization would seem to be the October 15th “Stay at home: Recommended” and “Travel: Recommended not to travel.” Germans will usually do what they are told to! The November 2nd restriction on group size, and the closure of some workplaces, have reduced Rt, but they don’t seem to have had much effect so far on case growth. And for much of November, Rt was well above 100%, but the new case counts weren’t consistently growing.

Ireland

Date

Stringency

Measures

20200808

59.72

Workplaces: Mandatory closed (Regional)

Gatherings: Up to 11-100 (Regional)

Stay at home: Required with exceptions (Regional)

Travel: Mandatory restrictions (Regional)

20200818

63.43

Events: Mandatory cancelled

20200921

52.31

Schools: Recommended closed

Workplaces: Some closed

Events: Mandatory cancelled (Regional)

Gatherings: Up to 11-100 (Regional)

Public transport: Recommended closed (Regional)

Travel: Recommended not to travel (Regional)

20201007

61.57

Schools: Recommended closed (Regional)

Events: Mandatory cancelled

Travel: Mandatory restrictions

20201021

81.48

Schools: Some closed

Workplaces: Mandatory closed

Gatherings: Up to <=10

Public transport: Recommended closed

Stay at home: Required with exceptions

Current (20201123): Schools: Some closed, Workplaces: Mandatory closed, Events: Mandatory cancelled, Gatherings: Up to <=10, Public transport: Recommended closed, Stay at home: Required with exceptions, Travel: Mandatory restrictions, International: Quarantine high-risk, Public info: Co-ordinated, Testing: If symptoms, Contact tracing: Comprehensive, Face covering: Required in some places.

Notes: The regional measures of August 8th seem to have brought the immediate problem under control. After that, nothing seemed to have much effect until October 7th. It was probably the national measures, “Travel: Mandatory restrictions” and/or the “Events: mandatory cancelled” that did the trick. And the (over?) draconian measures of October 21st have certainly brought Rt down, and to well below 100%.

Italy

Date

Stringency

Measures

20200808

50.93

International: Ban some arrivals

20200817

54.63

Workplaces: Some closed

20200914

47.22

Schools: Recommended closed

20201006

55.56

Gatherings: Up to 11-100

Public transport: Recommended closed

Contact tracing: Limited

Face covering: Required when with others

20201014

50

Public transport: Open

20201023

66.67

Schools: Some closed (Regional)

Workplaces: Some closed (Regional)

Gatherings: Up to <=10

Public transport: Recommended closed (Regional)

Stay at home: Required with exceptions (Regional)

Travel: Mandatory restrictions (Regional)

International: Quarantine high-risk

Contact tracing: Comprehensive

20201106

76.85

Schools: Some closed

Workplaces: Mandatory closed (Regional)

Stay at home: Required with exceptions

International: Ban some arrivals

20201110

79.63

Public transport: Recommended closed

Contact tracing: Limited

Current (20201125): Schools: Some closed, Workplaces: Mandatory closed (Regional), Events: Mandatory cancelled, Gatherings: Up to <=10, Public transport: Recommended closed, Stay at home: Required with exceptions, Travel: Mandatory restrictions (Regional), International: Ban some arrivals, Public info: Co-ordinated, Testing: If symptoms, Contact tracing: Limited, Face covering: Required when with others.

Notes: The August 17th closure of some workplaces did seem to have an effect. The package of measures on October 6th did have an immediate effect, but not as strong as the Italians might have hoped. October 23rd, for me, looks like the key date; and on that date, the only national measure was the restriction of gatherings to 10 or less. This looks like more evidence that restricting gathering sizes works.

Whether the strong restrictions added on November 6th have made a difference, or are simply “over the top,” I – once again – cannot tell; and it doesn’t help that the Italians haven’t reported any Rt figures since November 20th. But once again, an Rt consistently above 100% has nevertheless allowed case growth to drop significantly.

Luxembourg

Date

Stringency

Measures

20200807

31.48

Events: Recommended cancelled

Stay at home: Recommended

20200812

34.26

International: Screening

20200821

39.1

International: Ban some arrivals

20200825

43.52

Workplaces: Recommended closed

20200913

40.74

Gatherings: Up to 11-100

20200926

43.52

Gatherings: Up to <=10

20201006

43.52

Contact tracing: Limited

20201020

52.78

Schools: Recommended closed

Events: Mandatory cancelled

20201030

56.48

Stay at home: Required with exceptions

Face covering: Required when with others

20201126

60.19

Workplaces: Some closed

 

Current (20201123): Schools: Recommended closed, Workplaces: Some closed, Events: Mandatory cancelled, Gatherings: Up to <=10, Stay at home: Required with exceptions, International: Ban some arrivals, Public info: Co-ordinated, Testing: Open, Contact tracing: Limited, Face covering: Required when with others.

Notes: Because Luxembourg is a small country, its weekly case growth will tend to be more volatile than in larger countries. There were also significant adjustments to the numbers of cases in late August. Since then, a significant drop in weekly case growth seems to have started since the October 20th measures. I’m a little surprised by that, as school closures were only recommended, not mandated; perhaps the mandatory cancellation of events was a bigger factor.

The October 31st “Stay at home: Required with exceptions” also produced a drop in Rt, as you can see by the “knee” on the graph. But since then, case growth hasn’t come down much, even though Rt has continued to drop. As to the November 26th closure of some workplaces, we’ll have to wait and see.

Netherlands

Date

Stringency

Measures

20200818

50.93

Events: Recommended cancelled

Gatherings: Up to <=10

20200920

48.15

Events: Recommended cancelled (Regional)

20200929

62.04

Events: Mandatory cancelled

Travel: Recommended not to travel

20201104

65.74

Workplaces: Mandatory closed

20201122

56.48

Workplaces: Some closed

Travel: No restrictions

Current (20201122): Schools: Recommended closed, Workplaces: Some closed, Events: Mandatory cancelled, Gatherings: Up to <=10, Stay at home: Recommended, International: Ban some arrivals, Public info: Co-ordinated, Testing: If symptoms, Contact tracing: Comprehensive, Face covering: Required in some places.

Notes: The August 18th restriction on gathering size did seem to pull down the size of the next peak in case growth. How significant the recommendation to cancel events was, I don’t know. But Rt started to increase shortly afterwards, not to decrease!

The September 29th measures, events cancellation and recommendation not to travel, did seem to get the cases coming down at last. Rt also started to drop significantly, a week or so afterwards.

All was well for a while; and by the middle of November, Rt had dropped well below 100%. But the November 4th closure of workplaces seems to have had no beneficial effect at all. In fact, since the middle of November, Dutch cases have been dropping, but more slowly than before.

Portugal

Date

Stringency

Measures

20200801

65.28

Face covering: Required outside the home (Regional)

20200810

66.2

Events: Mandatory cancelled

Stay at home: Required with exceptions (Regional)

20200825

55.09

Schools: Recommended closed

Workplaces: Some closed (Regional)

Stay at home: No measures

20200904

56.94

Workplaces: Some closed

20200915

58.8

Stay at home: Recommended (Regional)

20201002

56.94

Workplaces: Some closed (Regional)

20201023

60.65

Stay at home: Required with exceptions (Regional)

20201024

66.2

Schools: Mandatory closed (Regional)

20201030

74.54

Travel: Mandatory restrictions (Regional)

20201104

66.2

Travel: No restrictions

20201106

60.65

Schools: Recommended closed

20201114

69.91

Workplaces: Mandatory closed (Regional)

20201116

66.2

Workplaces: Some closed (Regional)

20201121

69.91

Workplaces: Mandatory closed (Regional)

20201123

66.2

Workplaces: Some closed (Regional)

Current (20201123): Schools: Recommended closed, Workplaces: Some closed (Regional), Events: Mandatory cancelled, Gatherings: Up to <=10 (Regional), Public transport: Recommended closed, Stay at home: Required with exceptions (Regional), International: Ban some arrivals, Public info: Co-ordinated, Testing: Open, Contact tracing: Limited, Face covering: Required outside the home.

Notes: Since early September, all the lockdowns have been regional. They have been quite stringent. And they do seem to be getting on top of the virus, albeit slowly.

The peaks and troughs in Rt in Portugal don’t seem to correspond to any particular lockdown measures being introduced or released at the time. Rt did, however, drop during September, a period when some workplaces were closed nationally. And, though Rt is still well above 100%, new cases have started to drop significantly. The Portuguese must be doing something right; but I have no idea what it is!

Spain

Date

Stringency

Measures

20200810

60.65

Stay at home: Recommended (Regional)

20200814

62.5

Workplaces: Some closed

20200907

60.65

Schools: Some closed (Regional)

20201007

64.35

Schools: Mandatory closed (Regional)

20201013

64.35

Contact tracing: Comprehensive

Face covering: Required outside the home

20201022

58.8

Schools: Recommended closed

20201025

71.3

Events: Mandatory cancelled

Gatherings: Up to <=10

Stay at home: Required with exceptions

Travel: Mandatory restrictions

Current (20201129): Schools: Recommended closed, Workplaces: Some closed, Events: Mandatory cancelled, Gatherings: Up to <=10, Stay at home: Required with exceptions, Travel: Mandatory restrictions, International: Ban some arrivals, Public info: Co-ordinated, Testing: If symptoms, Contact tracing: Comprehensive, Face covering: Required outside the home.

Notes: The two sets of lockdowns during July do seem to have had an effect on both Rt and weekly case growth, but they were regional only. Another “sea change” seems to have taken place around October 25th. The measures introduced then were event cancellations, reduced gathering size, stay at home, and travel restrictions. All four of these have been seen to be effective elsewhere, so the Spaniards are probably on the right track as far as dealing with the virus is concerned. Here, too, we see Rt consistently above 100% during November, and yet a significant drop in new cases.

The face covering requirement introduced on October 13th – the most stringent in all the 14 countries – does not appear to have had any effect on Rt. And any effects it might have had on case growth will have been eclipsed by the measures of October 25th.

Sweden

Date

Stringency

Measures

20200817

55.56

Schools: Recommended closed

20201110

58.33

Travel: Recommended not to travel (Regional)

20201111

50

Gatherings: No restrictions

20201124

53.7

Workplaces: Some closed

Current (20201124): Schools: Recommended closed, Workplaces: Some closed, Events: Mandatory cancelled, Public transport: Recommended closed, Stay at home: Recommended, Travel: Recommended not to travel (Regional), International: Ban some arrivals, Public info: Co-ordinated, Testing: If symptoms, Contact tracing: Limited.

Notes: The weekly case growth has come down since the end of October, with no particular lockdown measure being an obvious cause. However, Rt – which is unusually smooth, like Denmark’s – has been rising since July, and now seems to have just about peaked. The November 24th closure of some workplaces hasn’t been in force long enough yet to draw any conclusions.

Switzerland

Date

Stringency

Measures

20200917

43.06

Face covering: Required when with others

20200918

43.06

Testing: If symptoms

20201010

33.8

Schools: Recommended closed (Regional)

Events: Recommended cancelled (Regional)

International: Quarantine high-risk

20201019

35.19

Gatherings: Up to 11-100

20201020

40.74

Events: Recommended cancelled

International: Ban some arrivals

20201029

45.37

Workplaces: Some closed

Events: Mandatory cancelled (Regional)

20201102

49.07

Schools: Some closed (Regional)

Current (20201123): Schools: Some closed (Regional), Workplaces: Some closed, Events: Mandatory cancelled (Regional), Gatherings: Up to 11-100, International: Ban some arrivals, Public info: Co-ordinated, Testing: If symptoms, Contact tracing: Comprehensive, Face covering: Required when with others.

Notes: This is an odd one. Rt went up enormously during September and early October, perhaps due to the re-opening of schools after the summer break. (There was a similar rise back in May, when schools re-opened after the first lockdown). Weekly case growth and Rt have been coming down almost continuously since then, and Rt is now down almost to 100%. Yet there was no national lockdown measure in early October to trigger that!

New cases peaked and started coming down around the time of the October 29th closure of some workplaces. Looking at Rt, there is a “knee” at precisely that time; so perhaps this measure added to the already existing downward trends in Rt and weekly case growth.

UK

UK wide measures


Date

Stringency

Measures

20200801

69.91

Travel: Mandatory restrictions (Regional)

20200813

66.2

Schools: Some closed (Regional)

20200830

66.2

Contact tracing: Limited

20200901

64.35

Schools: Recommended closed

20200914

65.74

Gatherings: Up to <=10

20200924

67.59

Stay at home: Recommended

20201012

60.19

Stay at home: Recommended (Regional)

Travel: Recommended not to travel (Regional)

20201019

65.74

Schools: Mandatory closed (Regional)

20201022

67.59

Stay at home: Recommended

20201023

75

Stay at home: Required with exceptions (Regional)

Travel: Mandatory restrictions (Regional)

20201106

75

Workplaces: Mandatory closed (Regional)

Stay at home: Recommended

Travel: Recommended not to travel

International: Ban some arrivals

20201110

63.89

Schools: Open

Workplaces: Some closed

Current (20201116): Workplaces: Some closed, Events: Mandatory cancelled, Gatherings: Up to <=10, Public transport: Recommended closed, Stay at home: Recommended, Travel: Recommended not to travel, International: Ban some arrivals, Public info: Co-ordinated, Testing: If symptoms, Contact tracing: Limited, Face covering: Required in some places.

Notes: The UK seems to have the best correlation between Rt and weekly case growth of all the countries. There was a sea-change from a rising to a falling Rt trend some time in September, only broken by the huge spike in early October. “Gatherings: Up to <=10” and “Stay at home: Recommended” may have helped with this.

Here is the new cases graph for the UK as a whole:


The “tiered” local lockdowns in place in the second half of October seemed to have just about stabilized the new cases. When a new national lockdown was introduced in early November, cases suddenly went up again! But they peaked around November 13th, and have been going down ever since.

The UK data is particularly difficult to analyze, not only because of the tiers system (a version of which comes back into force on December 2nd), but also because England, Northern Ireland, Scotland and Wales each have their own separate additional lockdown rules.

England (84% of UK population)

Date

Stringency

Measures

20200801

66.2

Stay at home: No measures

Travel: Mandatory restrictions (Regional)

20200827

66.2

Face covering: Required in some places

20200901

62.5

Schools: Recommended closed

20200914

63.89

Gatherings: Up to <=10

20200925

63.89

Face covering: Required in some places

20201012

65.74

Stay at home: Recommended (Regional)

20201105

74.07

Stay at home: Required with exceptions

Travel: Mandatory restrictions

20201117

66.67

Stay at home: Required with exceptions (Regional)

Travel: Recommended not to travel

20201130

68.52

Schools: Some closed (Regional)

Differences from UK wide measures (20201130): Schools: Some closed (Regional), Stay at home: Required with exceptions (Regional), International: Quarantine high-risk.

Notes: The August 27th “Face covering: Required in some places” almost exactly coincided with the start of the second wave. And after the September 25th tightening, cases went soaring! Not good evidence for the efficacy of face coverings. And despite “Schools: Recommended closed,” most schools did in fact re-open, and the results are visible in the cases graph.

Of the November measures, the most likely to have brought about the drop in cases were the stay-at-home requirement and the travel restrictions.

Northern Ireland (3% of UK population)

Date

Stringency

Measures

20200810

62.96

Face covering: Required in some places

20200824

57.41

Schools: Some closed (Regional)

20200831

55.56

Schools: Recommended closed

20200911

54.17

Gatherings: Up to <=10 (Regional)

20200922

55.56

Gatherings: Up to <=10

20200925

55.56

Face covering: Required in some places

20201014

77.78

Schools: Mandatory closed

Stay at home: Recommended

Travel: Mandatory restrictions

20201102

68.52

Schools: Some closed

Travel: Recommended not to travel

Contact tracing: Limited

20201110

66.67

Schools: Some closed (Regional)

Differences from UK wide measures (20201123): Schools: Some closed (Regional), International: Quarantine high-risk.

Notes: Due to the low proportion of the population, these measures are unlikely to have contributed much to the UK wide picture.

Scotland (8% of UK population)

Date

Stringency

Measures

 

20200805

71.3

Travel: Mandatory restrictions (Regional)

20200817

67.59

Schools: Recommended closed

20200821

73.15

Stay at home: Required, minimal exceptions (Regional)

20200824

70.37

Travel: Recommended not to travel

20200831

64.81

Stay at home: Recommended

20200923

64.81

Contact tracing: Comprehensive

 

20200925

64.81

Face covering: Required in some places

 

20201004

64.81

Contact tracing: Limited

 

20201102

67.59

Travel: Mandatory restrictions (Regional)

 

20201117

64.81

Events: Mandatory cancelled (Regional)

 

Differences from UK wide measures (20201123): Schools: Recommended closed, Events: Mandatory cancelled (Regional), Travel: Mandatory restrictions (Regional), International: Quarantine high-risk.

Notes: Due to the low proportion of the population, these measures are unlikely to have contributed much to the UK wide picture.

Wales (5% of UK population)

Date

Stringency

Measures

20200816

59.26

Stay at home: No measures

20200901

55.56

Schools: Recommended closed

20200908

62.5

Gatherings: Up to <=10 (Regional)

Travel: Mandatory restrictions (Regional)

20200914

62.5

Face covering: Required in some places

20200925

62.5

Face covering: Required in some places

20200928

66.2

Stay at home: Recommended

20201013

67.59

Gatherings: Up to <=10

20201016

70.37

Travel: Mandatory restrictions

20201023

77.78

Workplaces: Mandatory closed

Stay at home: Required with exceptions

20201109

64.81

Workplaces: Some closed

Stay at home: Recommended

Travel: Recommended not to travel

20201117

64.81

Contact tracing: Limited

20201123

66.67

Schools: Some closed (Regional)

Differences from UK wide measures (20201123): Schools: Some closed (Regional), International: Quarantine high-risk.

Notes: Due to the low proportion of the population, these measures are unlikely to have contributed much to the UK wide picture.

Some tentative conclusions

In many cases, it’s hard to establish a strong correlation between success against the virus and any one particular lockdown measure. Part of the reason is that governments like to make lots of different regulations all starting on the same date, so it’s hard to determine which worked and which didn’t. The following conclusions, therefore, can only be tentative.

While schools are well known to be a breeding ground for the virus, I couldn’t find any evidence that school closures, either recommended or mandated, have on their own caused a significant drop in case growth anywhere during the second wave.

Workplace closures appear not to have been beneficial in Belgium or the Netherlands, and their effectiveness in Germany is doubtful. There is, however, some evidence that they did make a difference in Italy; and perhaps in Portugal and Switzerland too.

In most of the countries, large scale events have been (and still are) cancelled. But when a country has relaxed this measure, re-imposing it often seems to have had a beneficial effect on new case counts; at least in Ireland, Luxembourg, the Netherlands and Spain. But there seems to have been no clear benefit from re-imposing this measure in Belgium.

The reduction in maximum gathering size to 10 or less seems to have been effective in Austria, Belgium, Italy, Spain and the UK. The only country where it doesn’t seem to have made much of a difference is the Netherlands.

Public transport closures do not appear to have been a significant factor during the second wave of the epidemic.

Stay at home requirements look to have had a significant effect. Even just recommending stay-at-home has produced effects in Austria, Germany and the UK. Mandating stay-at-home seems to have made a difference in Belgium and Spain, and perhaps in Luxembourg.

Travel restrictions, too, do make a difference. Even a recommendation not to travel has had beneficial effects in Germany and the Netherlands. Mandatory restrictions on travel have been effective in Ireland, and arguably in Spain. And a mixture of the two has, probably, had some effect in the UK.

The only countries which changed their international travel rules in October or November are Germany, Switzerland and Italy. I would expect that the effects of these changes will have been negligible; since international travel bans and quarantines would have far more effect in times when the virus is at a low level in a country, than when – as now – it is higher than in the rest of the world.

As to face masks for the general public, evidence from Belgium, France, Spain and the UK suggests that they have no beneficial effects. Indeed, it’s not implausible, given the data, that requiring the public to wear face coverings actually helps to spread the virus.

 

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