Contact restrictions have applied in Germany since March 23. Virologist Drosten explains why the measures were effective. Image: imago images / photothek
Lockdown senseless? This is how virologist Drosten rebukes his critics
The corona pandemic will not be stopped so easily. That is why it is now Germany’s declared goal to at least flatten the pandemic wave. In order to understand the flattening, experts calculate the number R: This is the infection rate and describes how many people are infected with a corona infected on average. At the moment the number in Germany is 0.9, which means that not everyone who carries the coronavirus is infecting someone else on average.
According to the Robert Koch Institute the number had already dropped in early March, before the lockdown on March 23. According to this, there was possibly no longer any exponential growth of the newly infected at this point. Therefore critical voices are increasing: The lockdown in Germany was unnecessary.
This graphic shows the course of the infection rate:
Other critics say the lockdown is ineffective: After all, over 2,000 people are still infected with the corona virus every day.
In his NDR podcast “Corona virus update“Virologist Christian Drosten from the Charité in Berlin sheds light on the dark theories about the supposedly unnecessary or ineffective lockdown and explains exactly what the infection rate is all about. In his opinion, there are four reasons why the number R has decreased since the beginning of March, before the lockdown:
People took action before they were ordered
According to the virologist, mobility data from mobile operators can be used to understand “that mobility will be greatly reduced in the whole of Germany as early as the week from March 9”. Drosten remembers:
At this point, the outbreak in Heinsberg became known, and recordings of catastrophic situations from Italy went through the media. The virologist suspects:
There has been a lot of public discussion about how we should proceed in the Corona crisis. According to Drosten, it is not true that the first social changes did not come until March 23.
The measures show their effects gradually and with a time delay
According to Drosten, the gradual introduction of measures has led to a gradual reduction in the number of infections. First, major events were banned, then the schools were closed – however, the level of infection in the household continued.
But since we can see that the number of new infections fell in early April and again in mid-April, in several stages, it is clear: The lockdown shows positive effects – albeit with a slight delay.
The measures could not be implemented in all social groups
The fact that there are still new infections with the corona virus is not because the population has not followed the measures consistently enough or because the lockdown is ineffective. But because the virus has now broken out in closed parts of society, for example in nursing homes or in hospitals. According to Drosten, these are …
“(…) special situations, where you basically have a situation almost like in a household, but much larger. And where these contact measures simply couldn’t work.”
This means that the virus could continue to spread to new people, but not in the general population. The measures were able to reduce the mass of infections. Nevertheless, there were people who were still exposed to contagion because the ban on contact and distance rules could not be implemented for them.
Test capacities have been increased since March
From mid-February to mid-March, the laboratories made a huge leap in terms of diagnosing the coronavirus, says Drosten. “There were 87,000 tests done each week starting March 2nd,” says the virologist. A week later there were already 127,000, another week later 348,000. “This is of course an extreme increase,” says Drosten.
Against this background, the expert explains that R depends not only on the number of newly reported cases that have been tested positive using the PCR tests, but also on the test capacities.
“That means we had two effects that occurred at the same time: namely the increase in the possibilities to recognize this at all, and then the real increase (of new infections).”
Drosten therefore has strong suspicions: Before, we had two increases in parallel, namely that of the newly infected and that of the test capacities. As a result, we had a sharp increase in the number of cases reported. Test capacities are now stagnating, they are not increasing. The fact that the number of reported cases no longer increases can also be due to the fact that we simply cannot test more people.
The conclusion regarding the number R is: It cannot really be calculated exactly because we cannot know what the real number of infected people is. It could also be a statistical bias that the infection rate has decreased.
The criticism that the lockdown would be unnecessary or ineffective is not justified
According to Drosten, the researchers will carry out further calculations on the number R in order to investigate the situation more closely and to avoid distortions. Nevertheless, the virologist says: The effects he mentioned could be held against the assumption that the lockdown would have brought nothing.
Drosten also talks to the NDR in his podcast about a possible vaccine from China and the role of T cells in immunity. You can find the whole podcast here.