German school finds DIY answer to ward off coronavirus

Keeping the windows open to combat Covid-19 is easier said than done as winter approaches. One German school believes it has found a cheap and simple solution with a DIY ventilation system designed by a teacher's scientist husband.

German school finds DIY answer to ward off coronavirus
An open window at a school in Stuttgart. Photo: DPA

“It works like a kitchen extractor fan,” said inventor Frank Helleis, standing in a classroom at the IGS Mainz-Bretzenheim secondary school.

Above every desk hangs a clear plastic funnel attached to a narrow pipe, with all the pipes in turn connected to one wide pipe leading to a fan that directs the air outside through a tilted window.

Warm breath exhaled by the pupils, potentially carrying virus-laden tiny particles known as aerosols, rises up overhead and is sucked through the tubes and pushed outside before it can spread through the room.

READ ALSO: Lüften: Why are Germans so obsessed with the art of airing out rooms

Another window is kept ajar to allow in fresh air.

Tests carried out by the prestigious Max Planck Institute for Chemistry, where Helleis works, have shown the system manages to remove over 90 percent of aerosols from the room, on par with the most high-tech air filtration units on the market.

The difference is that Helleis' light-weight contraption can be built from materials from the do-it-yourself store for around €200.

A handful of volunteers put it together in half a day, he said, and the Max Planck Institute has shared the assembly instructions online for anyone who wants to copy the idea.

Extra sweater

The timing could scarcely be better.

Germany's coronavirus numbers have been climbing at an alarming rate and
regularly airing out classrooms is considered key to keeping schools open —
regardless of the weather outside.

Sophia Wettig, 18, keeps an extra jumper in her locker. She said she finds it hard to concentrate in the cold and it was “pretty cool” her school had come up with a warmer solution.

“It's more pleasant being here than in other rooms,” she told AFP from behind a face mask, which she and her classmates keep on during lessons.

Helleis has already received almost 3,000 inquiries about the ventilation system, and expects it will be rolled out in many more schools.

Pupils wear jackets indoors next to an open window at a school in Gütersloh, North-Rhine Westphalia. Photo: DPA

The inspiration came from brainstorming with his colleagues about how they could help in the pandemic.

“We figured the best thing to do was to carry out the trash,” he said, referring to being rid of any virus-carrying aerosols.

Because his wife teaches at IGS Mainz-Bretzenheim, he reached out to
headmaster Roland Wollowski who, as a scientist himself, was immediately on

His school in western Germany happens to be just a five-minute drive from
another Mainz institution making headlines, the BioNTech company leading the
race for a Covid-19 vaccine.

READ ALSO: BioNTech: Four things to know about the German firm leading the Covid-19 vaccine race


The official guidance from Germany's federal environment agency is for schools to open windows for several minutes every 20 minutes to reduce the infection risk.

But not all of Germany's roughly 40,000 schools have windows that fully open, and confusing advice about air purifying machines and other alternatives has left many educators scratching their heads, said Heinz-Peter Meidinger, president of the German Teachers' Association.

The association has been “overrun” with offers from firms trying to sell their air filtration systems, he said, with prices swinging from €1,500 to €6,000 per unit.

Politicians have been slow to address schools' concerns about aerosols, probably because many options are “too expensive”, he told AFP.

Under Germany's federal system, responsibility for schools lies with each of the country's 16 states.

To date, just six state governments have pledged funding to address ventilation issues.

READ ALSO: Stofflüften: The new German guidelines for when someone sneezes

The regional government in wealthy Bavaria has committed €50 million, although Meidinger expects that will also be spent on low-cost tools like CO2 readers that alert teachers when it's time to air a room.

Helleis says portable air purifiers equipped with high-efficiency filters can be useful in schools, but are more expensive, noisier and more energy-consuming than his prototype.

And unlike his invention, they don't also remove CO2 from the room, which
has been blamed for causing tiredness, giving schools a reason to keep his
homemade system even after the pandemic.

Headmaster Wollowski plans to spend the next few weekends installing Helleis' system in all the school's classrooms, helped by parents, teachers
and pupils.

“Everyone is very motivated,” he said.

By Michelle Fitzpatrick

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Pandemic in Germany unlikely to end this year, says top virologist

High profile German virologist Christian Drosten believes Germany will see a severe spike in Covid infections after summer, and that the pandemic will not become endemic this year.

Pandemic in Germany unlikely to end this year, says top virologist

Drosten previously said that Germany would probably be able to declare the end of the pandemic this year.

But in an interview with Spiegel, Drosten said he had reevaluated his opinion. 

“When the Alpha variant came, it was very surprising for me. When Delta appeared I was sceptical at first, then with Omicron we had to reorient ourselves again. And since January there have already been new Omicron subtypes.

“So I would actually like to correct myself: I no longer believe that by the end of the year we will have the impression that the pandemic is over.”

READ ALSO: End is in sight for pandemic in Germany, says virologist 

Drosten also said that Germany will not see a largely Covid-free summer, which has been the case in previous years, and a further increase in infections in autumn. 

“We are actually already seeing an exponential increase in case numbers again,” Drosten said.

“The BA.5 variant (of Omicron) is simply very transmissible, and people are losing their transmission protection from the last vaccination at the same time.”

In other countries, he said, when the number of cases become high, hospitalisation and death rates also rise again. “Unfortunately, that will also be the case here,” said Drosten, but added: “Overall, however, far fewer people will become seriously ill and die than in 2021.”

Drosten said he expected many more infections from September.

“I hope that the school holidays will dampen the increase in cases somewhat. But from September, I fear we will have very high case numbers,” the head of the virology department at Berlin’s Charité hospital told Spiegel.

READ ALSO: German Health Minister lays out autumn Covid plan

Virologist Christian Drosten at a Covid press conference in 2021.

Virologist Christian Drosten at a Covid press conference in 2021. Photo: picture alliance/dpa | Kay Nietfeld

If the government does not take any action, he predicted there would be a lot of sick leave across all industries. “That will become a real problem,” he said.

Drosten said he did not expect overcrowded intensive care units in Germany.

But the new BA.5 sub-variant, which is becoming dominant in Germany, may affect people more strongly. 

“The wheel is turning more towards disease again,” said Drosten. It is not true that a virus automatically becomes more and more harmless in the course of evolution. “That makes me even more worried about the autumn,” he said.

Drosten recommends wearing masks indoors during the colder months, saying it is “the least painful” measure.

If, in addition, “up to 40 million people could be immunised or given a booster vaccination” before winter, for example by urgently calling for company vaccinations, that would “really make a difference”, Drosten said.

In the long term, he said it’s inevitable that people will become infected with coronavirus.

He said the population immunity due to vaccinations and infections will at some point be so strong that the virus will become less important. “Then we will be in an endemic state,” said Drosten. In the worst case, however, this could take “several more winters”.

However, Drosten warned against people trying to deliberately infect themselves with Covid, saying getting the infection in summer doesn’t mean people will be protected in winter. 

Drosten himself said he has not yet contracted Covid-19.

“So far, I guess I’ve just been lucky,” he said. “I rarely put myself in risky situations, but I’m not overly cautious either.”

‘Pandemic depends on behaviour’

According to the Robert Koch Institute (RKI)’s latest weekly report, more outbreaks are occurring in care homes, and the number of patients in intensive care units is slightly rising as infections go up. 

The institute said there had been a 23 percent increase in the 7-day incidence compared to the previous week. On Friday the 7-day incidence stood at 618.2 infections per 100,000 people. There were 108,190 infections within the latest 24 hour period and 90 deaths. 

“The further course of the pandemic depends not only on the occurrence of new virus variants and the uptake of vaccinations on offer, it also depends to a large extent on the behaviour of the population,” said the RKI.

According to the DIVI intensive care register, the number of Covid-19 patients in ICUs had increased to 810 on Thursday this week, from about 600 at the beginning of the month.

However, that number is still low compared to previous Covid peaks when thousands of people were in intensive care in Germany.