'Target clusters and superspreaders': Here's how Germany could prevent a second coronavirus wave
Top virologist Christian Drosten recommends a new strategy for Germany to stop a second wave of coronavirus hitting in autumn.
How can Germany ward off a large increase in coronavirus infections? By targeting clusters, finding superspreaders and looking to Japan.
That's according to world-leading expert on coronaviruses, Christian Drosten, who recommends a change in strategy in the fight against a second large outbreak of coronavirus this autumn.
Drosten, of the Charité in Berlin, says finding and isolating transmission clusters instead of testing everyone could be the way forward.
In a guest article for Die Zeit and reported on by several German media outlets, Drosten said that the outbreak behaviour in Germany had changed since spring. More and more people from different backgrounds and of varying ages are becoming affected, Drosten said.
"While most chains of infection have been traceable so far, new cases may soon appear everywhere at the same time, in all districts, in all age groups," he said.
In order to keep the virus under control until a vaccine is available, Drosten recommends looking to Japan, where the first wave happened without a lockdown despite a large number of imported infections.
Drosten said Germany had tried to carry out widespread testing in order to be able to trace every chain of infection.
Instead, Japan has relied on masks as well as detecting and isolating infection clusters. Rather than eliminate the risk of infection, the objective is to stop the spread of the disease to keep the number of patients to a minimum.
So the focus is on situations that scientists say are typical for the spread of the coronavirus. This includes work in slaughterhouses or open-plan offices, for example, but also private family celebrations, church services, sports clubs and night clubs or bars.
Record transmission clusters
In order to identify these kinds of clusters, Japan has drawn up "official lists of typical social situations in which transmission clusters arise and made them public", said Drosten.
Christian Drosten. Photo: DPA
The virologist says health authorities then specifically look for these kinds of situations in the contact history of a detected case.
For Germany, this means that, in the event of an overload, authorities would only order measures for those who test positive if the infected person possibly belongs to a cluster.
In this way, health authorities wouldn't get overburdened. "After all, you can't test the virus away, you have to react to positive tests," he said.
Germans should keep a 'contact diary'
According to Drosten, the idea to change strategy becomes clear when you consider how differently the virus spreads: some patients only infect one other person, others – who are dubbed superspreaders – infect 10 or more.
However, while individual carriers do not play a role in the exponential spread of the pathogen, a cluster with a multiple carriers might start several new chains. Drosten therefore recommends that every citizen in Germany should keep a "contact diary" in order to be able to identify potential clusters as quickly as possible and without testing:
"There is no time for testing," said Drosten.
In order to implement this strategy, however, according to Drosten, the responsible public health officers would need "binding guidelines to which they can refer".
"Which everyday situations, which group sizes are particularly risky?" he added.
Apart from the open-plan office, this could also apply to school classes, he said, and Germany should be prepared for this in autumn, he warned.
"The Japanese strategy could help to keep schools open longer," said Drosten, "by stopping clusters in classes before entire schools have to close".
German parliamentarian and health expert Karl Lauterbach also said Germany should change its tactics. He recommends honing in on so-called super-spreaders – those who pass the virus onto many people.
In an interview with Spiegel, Lauterbach said contact tracing was "totally inefficient".
"Instead of contacting each individual contact by phone, the authorities should focus their efforts on so-called superspreaders, those few highly contagious cases that often infect dozens of people in group situations.
"They alone are the driving force behind the pandemic. We now know that individual transmitters have almost no effect on the exponential growth. If we don't change course on this issue, the second wave will be intense."
Testing and trust
Drosten said Germany made it through the first wave in fairly good shape because of testing at an early stage as well as trust between people, the government and scientists.
The lockdown was "early and short" and "saved the economy a lot of damage", he said. Now, however, there is a danger of "gambling away" this success.
Although we are learning a lot about the virus, we are only "hesitantly" implementing the findings, he said. "The challenge is to know our scope for action for the exceptional period that will elapse before the vaccination is available," Drosten said.
If Germany doesn't act then previous success, both medical and economic, could be lost, said Drosten.
In order to be able to react adequately to a second wave, we must first understand the differences to the first. For example, the virus initially entered the country from outside, but in the second wave it will spread "out of the population".
This could trigger a different dynamic and – especially at the end of the holiday season – lead to new cases occurring in many places at the same time. This would overburden the "poorly staffed" health authorities, he said.