Leon Grice
Europe's second wave?
European countries have increasing COVID-19 reproduction (Reff) values above 1.0 and that has been true for some time. We first noticed the trend a few weeks ago when our blog posts were focused on trends in US states and counties. Now it's Europe's turn. Here is a screenshot from 17 August from: https://covid19.closeassociate.com/region/de

Remember that Reff is the best leading indicator of where daily new cases will be in 10-14 days - a good short term predictor. Also if you combine increasing Reff values and high daily case numbers you have some of the conditions that result in health systems and communities becoming overwhelmed.
Spain and France
In other words if you are Spain with Reff=1.5 and new daily cases of 16,269 on 17 August there is a lot of work to be done to get Reff<1.0. The same applies for, France which has Reff=2.0 and 3,344 new daily cases on 17 August. France's Reff went above 1.0 on 25 June so 7-8 weeks of positive growth in COVID-19 cases. Spain's Reff went above 1.0 on 27 June.

Ireland and Greece
In contrast, on 17 August, Ireland has Reff=2.7, the highest in Europe, but 56 new daily cases which is a relatively smaller number. Likewise, Greece's Reff=2.7 and has 147 new daily cases. Greece's Reff went above 1.0 at around the beginning of June, whereas Ireland's went above 1.0 in the last week of July.
You can see the difference in the two countries' disease spread below. Perhaps, Ireland had a superspreader event that triggered the shift in Reff in late July. Whereas Greece has had a slow build up since June when our highly sensitive Reff method identified an increasing disease spread (above 1.0). Whether Greece has its mini-second wave under control is yet to be reflected in our Reff curve.

The UK and Le Weekend
The UK's Reff went above 1.0 on 14 July, over a month ago. On 17 August the UK's Reff was 1.2 with 713 daily cases. The UK's first wave of infection ran through March and April peaking a few times at 5,500 daily cases. You can see below that the UK started to experience an increase in daily cases by early August. UK's Reff seems to be coming down but if it stays above 1.0 you can expect daily cases to increase.
The sawtooth pattern in the reporting of the UK's daily cases took us a wee while to work out, but then we realised that the regular two point troughs and the five point peak pattern is most likely a working week. Perhaps testing is not taking place on some weekends in the UK. The UK is not alone in having a seven day data pattern. Our method has been designed to see through these kinds of data effects to get a more consistent Reff value.

Italy and Germany
On 17 August, Germany (Reff=1.54 and 1,693 cases) is show a steadily increasing curve of new cases and their Reff has been above 1.0 since 24 June. COVID-19 has had seven weeks above 1.0 to spread in Germany. On 17 August, Italy (Reff=1.4 and 320 cases) is also starting to see increasing cases while Reff has been above 1.0 since 16 July. These are relatively small numbers of cases for the size of their total populations so they may have time to bend Reff below 1.0 before exponential growth takes over.

The Nordic countries deserve their own blog post because you have countries with completely different mitigation strategies which you can see in the data. But some short takeaways are:
Norway, Denmark and Finland have significantly higher Reff values than Sweden, but Sweden has much higher daily cases.
Belgium and the Netherlands countries have quite high daily cases to their total populations but their high Reff values are bending back towards 1.0.
To put it simply, Russia's data is hard to understand.
The next blog post will look at South Korea which is experiencing an alarming increase in Reff at the moment. Watch that one closely.