Coronavirus: how likely is a second wave in Switzerland?

Japan is experiencing a second crown wave: these scenarios are expected in Switzerland

What happens after June 8? A team of researchers from ETH Lausanne shows how much the maintenance of hygiene and distance rules could affect the spread of the virus.

It would be the worst case scenario for Switzerland: after all the stores are reopened and a kind of normality is restored, the number of infected people increases again in the middle of summer. A second wave of infection hits us and a second blockage would be inevitable.

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How likely is this scenario? The Social Security and Health Commission wants to be prepared for this and presented a motion to the National Council on Wednesday. The Federal Council must evaluate and prepare measures for a “potential” spread wave “as soon as possible.”

An ETH Lausanne research team has already addressed this. The team described three scenarios through October. But first a look abroad, where some countries already face a second wave of the crown.

Situation in other countries.

Japan was the first country after China to experience the new corona virus. The country was able to avoid a rapid expansion for the time being with measures taken quickly. The Japanese chose to follow up on contacts, voluntarily stay home and wear a mask.

As of March 21, fewer than 1,000 people were infected in Japan. But discipline weakened despite slight measures; The mask was increasingly dispensed with and even parties were held.

This negligence had an impact on the number of infections: in a few weeks, the number of infected people increased to more than 14,000. This increase is already known as the second wave of infections.

In early April, Governor Yuriko Koike called for public events to be canceled and the facilities closed. Restaurants and shops remain open: the state appeals to the personal responsibility of citizens. Furthermore, a state of emergency has now been declared for all prefectures in Japan; after early April, this only applied to Tokyo and other major economic centers.

Cases have also increased again in China, South Korea, and Singapore. These were mainly people who entered the country and were already infected with the virus upon entry.

Germany and Austria warn about the second wave

The second wave is also being discussed in neighboring countries, Germany and Austria. Chancellor Angela Merkel explicitly warned of this a week ago. In recent days, the number of reproductions in Germany has increased slightly, from 0.7 to 0.9. Currently it is 0.76.

But that is not related to the opening of the store. The increase comes from Easter weekend, Michael Meyer-Hermann of the Helmholtz Center for Infection Research told Zeit Online. It was unclear if it was because people had more social contacts during the Easter holidays. If that were the case, one could estimate how sensitive the playback number is to fluctuations in the number of contacts and how thin the states are moving.

At a press conference, Merkel calculated: If the number of reproductions increased to 1.3 again, there could be so many infected in early June that the health system would be greatly overloaded. Berlin-based virologist Christian Drosten also said on the “NDR” podcast that he would not be surprised if the situation in May or June was difficult to control after this relaxation.

Even in Austria, where relaxation has been done before, one remains on guard against a second wave. The number of reproductions in Austria is currently assumed to be 0.59. But: “A second wave is not unrealistic, on the contrary: we must assume that it will come to us,” Eva Schernhammer, head of the Department of Epidemiology at the Vienna University of Medicine, told ORF.

She hopes the virus will return in the fall. Also because the disease spreads worldwide and could be reintroduced after successful local control. However, summer could help keep the virus at bay. In order to avoid the second wave, sufficient capabilities are needed to be able to assess everyone, not just vulnerable groups, as quickly as possible, says Schernhammer. In a second step, contact tracking and targeted isolation are important.

Scenarios for Switzerland

Does Switzerland now threaten the same as Japan? The answer is simple: it depends on how well the rules of distance and hygiene continue to be observed in this country. Because this behavior influences the Reproduction number R0.

The number of R0 reproductions in Switzerland was over 2.5 at peak times. Thanks to the block, ETH Zurich estimates it at around 0.7 as it reports to Tages-Anzeiger. But after relaxation, this value will increase again. The question is: for how much?

A team of experts from ETH Lausanne and Johns Hopkins University in Baltimore solved three possible scenarios for Switzerland.

In First Stage Experts assume that from May 1 it will return to normal and that all measures, such as hygiene and distance regulations, will be eliminated. It would quickly return to a similar point in early March, when the virus was accelerating in Switzerland.

In second Stage The number of plays is supposed to increase due to loosening as well, but will level out to around 1.5.

The most optimistic Stage is that Number Three: Here you manage to push R0 to 1.2. And Jacques Fellay, a member of the ETH Lausanne team of authors, considers this to be “very realistic” compared to the “Tages-Anzeiger”.

The impact on the health system.

The experts calculated several simulations with different parameters for each scenario.

That stinks Scenario 1 Immediately in the eye: if we cancel all measures, the second wave in June would hit us with great force: at peak hours, up to 30,000 people would have to be hospitalized.

With the optimist Scenario 3 With a reproduction number of 1.2, the peak of the second wave towards the end of summer would be similar to that of early April. However, the wave would last for several months. The research team’s scale runs through October 2020, but the curve is not yet completely flattened.

How many would have to go to the intensive care unit?

Of course, it is of particular interest how many of these hospitalized patients would have to be transferred to an intensive care unit.

Thanks to the update in recent weeks, Switzerland has around 2000 beds in intensive care units. With one Scenario 2 (i.e. an R0 value of 1.5) almost all people could be treated and need treatment in the intensive care unit.

Without further hygiene and distance measures, according to the experts’ model, the situation would be similar to that of northern Italy: doctors would have to classify.

How many would be infected?

How many people in Switzerland would be infected with the corona virus? Currently, Switzerland has positively evaluated around 30,000 people, in addition there is an unreported figure difficult to estimate. The ETH Lausanne forecast shows the following scenarios for the period up to September 15, 2020:

How many would die

And how many would die of COVID-19? Reminder: Switzerland currently registers around 1,400 deaths.