Half of the following statements are false. Find out which by interacting with the visualisation dashboard below.
Confirmed cases is the number of people who have tested positive to covid-19. Of course, we don’t test everyone, so we are definitely missing the real number of infected. The question is, by how much? A good indication is to look at how many tests have been done for every positive result. If we have done 100 tests for every positive one (1% ratio), our total numbers are probably much more accurate than having done 2 tests for each positive one (50% ratio). Ok, so I can look at the total confirmed cases, and then on the positive ratio, come up with a fancy calculation formula and then I’ll know. Getting closer, but not there yet. Testing is carried out very differently in different parts of the world. Some countries count the number of people tested, others the number of samples tested, and for many countries we don’t even have data. Some countries test widely, some narrowly in high risk populations, others use track and test systems and so on. All these different approaches cannot be accurately quantified at this point, but some data is better than no data.
If confirmed cases are so complicated, we can just look at the death data, right? Sure. Just remember that covid-19 deaths are counted slightly differently in different places. Sometimes even on the same place in different times. For instance, in the UK, up until the 12 of August all deaths following a positive covid-19 test were counted in the covid-19 death sum. Then, officials decided to only include deaths occurring up until 28 days after the initial positive test cutting down the total number of deaths by over 5 thousand. In many other countries, covid-19 needs to be specifically listed in the causes of death of a patient. And of course, covid-19 is rarely the only cause of death, so how do I even know what the patient died from?! First of all, take a deep breath and relax. You can’t know, but the professionals filling out those death certificates have had some practice. This is not a new problem. Terminally ill people are very often challenged in multiple fronts. Another way to look at death data, is to simply sum up all deaths occurring over a week and compare the total sums with previous years. The gross simplification here is that any excess deaths this year should correspond to covid-19’s impact. True, but impact is not just people directly dying from covid-19, but also from the side effects of the pandemic. Like hospitals being full, patients avoiding to visit them out of fear and so on.
Recovery definitions similarly vary between countries. Additionally, as we are mostly focused in new cases, severe conditions and deaths we might be less effective tracking people that simply get better and wander off. For instance, the CDC guidelines for a covid-19 recovery includes two negative tests following infection and easing of symptoms. But what happens when there is a test shortage, or people simply fail to show up for additional testing? Some countries like the UK and Sweden don’t even provide any recovery data.
All the additional metrics should be seen in context of the above. The death rates only make sense if there is adequate testing to record reliable data on confirmed cases. Recovered ratios and active data depend on the accuracy (and existence) of reliable recovery data.
Wherever you were, chances are that sometime during March or April you were told to stay home. Some governments merely outlined recommendations for the public, but most enforced rules to make citizens comply. Here you can see a rough visualization of government responses when it came to public movement restriction. For simplicity I am only using 4 broad categories of responses, but you can find more specific information by hovering over each country. The four categories range from no restrictions imposed (although recommendations are always made), to movement restrictions only in parts of the country, to restrictions for the whole country but only in particular times (curfew), to restrictions in the whole country all of the time (lockdown). Of course, many more government responses were put in place at the same time like banning gatherings, imposing social distancing rules, closing businesses etc, but the scope of this visualisation remains solely the movement restriction policies.