'An epidemiological mystery': Why Is COVID-19 so much deadlier in some countries than others?

Imagine you're a chief public health officer and you're asked the question on everyone's mind: how deadly is the COVID-19 outbreak? With the number of cases worldwide approaching 200,000, and 1,000 or more cases in 15 countries, you'd think there would be an answer. But the more data we see, the tougher it is to come up with a hard number. A four per cent death rate is pretty high — about 40 times more deadly than seasonal flu — but no experts believe that is the death rate. The latest estimate is that it is around 1.5 per cent. Other models suggest that it may be somewhat lower. The new epicentre of the outbreak is in Europe, so let's focus there. The graph below shows the crude (not adjusted for age) death rates in the ten countries with the most reported cases (all 1,000 or higher).

Let's look at the European extremes: Italy and Germany. Italy has the most cases (28,000) but Germany has more than 7,000 and its number is growing rapidly. Yet Italy's death rate so far is 35 times higher than Germany's. Moreover, only two of Germany's 7,200 active cases are classified as serious or critical, while in Italy it's 1,850 out of 21,000. In Canada there have been four deaths among 422 cases and only one of the 407 active cases is serious or critical. What's going on here? No one has a ready answer...MORE