[ad_1]
WWhile the country is again and again facing new highs in daily corona infections, the question arises about the proper interpretation of these numbers, such as at the beginning of the pandemic. Its development, as it seems clear, is a cause for great concern: since each newly infected person can cause more infections, the numbers increase faster and faster whenever the spread cannot be effectively contained through extensive testing and contact tracing.
This exponential growth is known from biology. Bavarian Prime Minister Markus Söder named as an example a pond on Wednesday, whose carpet of water lilies doubles in size every day. The development of this exponential growth goes against our intuitions: if the pond is half covered after 47 days, then it will be completely covered the next day. The spread of water lilies is accelerating enormously. The mechanisms of exponential behavior were already widely discussed in the spring. We are currently seeing this accelerated growth in the number of cases.
However, more information is needed to read these numbers correctly. First, the question arises as to how far current testing practice determines the numbers. Compared to spring, this effect is certainly decisive. Between March and June, the number of tests per week fluctuated around 400,000, and between 1.1 and 1.2 million since the end of August. This has led to the fact that an increasing number of mild cases were found in the course of extended testing and the current figures are only partially comparable to those of the spring.
However, the current increase is taking place with testing capacities that have remained roughly the same for weeks and thus appears to reflect real growth in the number of infections. This is also underscored by the positive test rate, which has grown steadily since the beginning of September: from an initial 0.7 percent to 3.6 percent last week. This quota provides indications of the extent to which testing capabilities can cope with actual outbreaks. In countries where an outbreak is out of control and many cases go unnoticed, this is reflected in high values, as currently in the Czech Republic, where more than one in four tests are positive.
The age distribution of those infected is also of central importance for the classification of numbers, because this determines the expected number of severe courses. The evolution of the demographic distribution of infections collected by the Robert Koch Institute (RKI) shows, on the one hand, that the group over 60, especially at risk, was well protected during the summer. That this fact explains why the repeated increase in the number of cases was initially not accompanied by a corresponding increase in the number of deaths, is also suggested by new calculations from scientists working with Viola Priesemann of the Max Planck Institute for Dynamics and Self-Organization. .
You can read all the current developments on the corona virus on the FAZ live blog.
However, since the end of September, significantly more infections have also been reported in the elderly population. These cases of infection will only become visible in intensive care units and in the number of deaths after a delay of several weeks. These demographics show, however, that the strategy of deliberately isolating particularly vulnerable citizens from infections that are spreading to other age groups obviously has limits.
Finally, the information on the location of the respective outbreaks, which the RKI now provides regularly, is of interest for the classification of the numbers. In the context of uncertainties, a clear trend is observed: if the data are analyzed throughout the year, the proportion of infections that occurred in the private context has increased considerably. This trend has two readings. The downside: there is a higher proportion of infections that are relatively difficult to control. The positive: at the same time, these are the transmissions that can most easily be prevented through responsible action by each individual.
