Sunday, 17 May 2020

Daily COVID-19 charts of selected countries

UPDATED 29-05-2020

From January to early May COVID-19 appeared to rise inexorably across the world. From mid-May, most of the early affected countries in the hotspots of the USA and Europe appeared to have reached a peak and begun a decline in new daily cases as the control measures began to have an effect.

This post will chart the progress after the peak. For information on COVID-19 gleaned during the first COVID-19 peak -see post "State of Covid-19, caused by the SARS-CoV2 virus, on 16th May 2020" available here USA figures from their CDC, UK figures from UK Department of Health and Social Care and Public Health England, Global and other EU data from WHO situation reports.

Perhaps the most amazing and reassuring feature of global cumulative cases is that we are seeing a linear increase in numbers, rather than the exponential one in the early days.  Figures 1 and 2 show a normal plot of cumulative COVID-19 cases and deaths, and a logarithmic plot to base 2 which makes it easier to compare the numbers of both on the same chart.

Charts 1 to 5 are important because they show the number of total cases over time for the world and for selected countries, which are large and remarkable. Cumulative global cases to date: 5,701,337; cumulative global deaths due to COVID-19 to date: 357.688.

Figures 1 and 2 appear to suggest that the number of cases is beginning to increase at a faster rate again.

Figure 1. Linear plot of both cumulative COVID-19 cases and deaths

Figure 2. Logarithmic plot of both cumulative COVID-19 cases and deaths

Most of the cases up to May were in Europe and then the USA. The USA had so many more cases than any other country, that it had to be plotted on its own as in figure 3. It too is linear rather than exponential, showing that there was some control of the disease, just not enough to shut it down.

Figure 3 Cumulative cases of COVID-19 in the USA
Only the UK shows a similar linear plot to the USA, though at a 5 fold lower level. It is only just beginning to flatten off. This contrasts with the other western EU countries which transitioned from exponential increase to gradual slowdown fairly early on. Russia, a late-comer to the epidemic, showing a steep exponential increase and then starting to transition to a slowdown.

igure 4. Cumulative COVID-19 cses over time for France, Germany, Italy, Russia and the United Kingdom

Figure 5 shows the six countries in a logarithmic plot.

Figure 5. Logarithmic plot Showing the contrast of west European countries to the UK and to Russia

The next two charts are key to showing whether countries have managed to gain control over the COVID-19 epidemic. What we all want to see is that the number of new cases per day is decreasing. The day to day data varies quite a bit. To even out the curve to see the underlying trend, I plot the  average of the values for the 7 days including the most recent day. 

Figure 6. again shows the USA data on its own because, well, the USA does everything more bigly than anyone else, including an epidemic, with numbers of new cases per day is more than two times higher than even high scoring Russia, nearly ten times higher than the UK and 40 times higher than Germany.

Figure 6. 7 day average of new daily cases in the USA, showing the slow decline beginning from a peak in mid-April.

Looking at how the different European countries got their epidemics in control, the UK stands out compared to the other western European countries by having a long plateau for over a month before new cases clearly began to decrease - see figure 7.  Russia's decline in cases has slowed down. New cases in the UK are still considerably higher than in other European countries.

Figure 7. Plot of new daily cases, averaged over the past 7 days, showing how epidemics reached their first peak in different countries other than the USA before control measures began to reduce new cases day by day.