Use of air purifiers at two daycare centres in Helsinki led to a reduction in illnesses and absences among children and staff, according to preliminary findings of a new study led by E3 Pandemic Response.

Air purifiers of various sizes and types were placed in two of the city's daycare centres during cold and flu seasons.

The initial results from the first year of research are promising, according to researcher Enni Sanmark, from HUS Helsinki University Hospital.

"Children were clearly less sick in daycare centres where air purification devices were used — down by around 30 percent," Sanmark explained.

The air purifiers were changed at two daycare centres serving as a control in the experiment, in order to rule out the effect that possible epidemic fluctuations could have on the results. The study's next phase will continue until April.

"We will be able to analyse whether there were only decreases in flu-type illnesses or whether the use of air purification could also help reduce stomach ailments," Sanmark said.

On average, daycare centre-aged children suffer 10-13 infectious illnesses every year, with each illness lasting from one to three weeks, according to the research.

Meanwhile, kids between the ages of 1-3 come down with flu-like symptoms between five to eight times a year — and children also often suffer stomach bugs, on top of that. Kids are particularly prone to catching colds after returning to daycare after their summer break.

Those illnesses are often shared by the kids' parents and daycare staff, prompting absences from work.

Sanmark said that employers face costs of around 370 euros for one day of an employee's sick leave.

"It would be a big savings if we could get rid of 30 percent of sick days spread by children, as well as the illnesses that go home to parents," Sanmark said.

The research aims to help build an air purification scheme that could be used at other daycare centres — namely how to get the air cleaner at such facilities in ways that aren't too noisy, expensive or take up too much space.

The final results of the study are expected next spring.

"At the moment, we are cautiously positive. Daycares and schools [here] have not done this before, but of course results from around the world show that air purification can reduce pathogens in the air, so our results are in line with these findings. We're excited and will continue our research," Sanmark said.

Prompted by the Covid-19 crisis, the E3 Pandemic Response project is a private and public effort that aims to "harness modern science and technology to create effective countermeasures to prevent the spreading of novel infectious diseases".

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