Air purifiers do not reduce the risk of being contaminated by a pathogen, such as a virus, and getting sick, according to a new study.
- Devices such as germicidal lamps, ionizers or air purifiers would not be so effective.
- The risk of being contaminated by a pathogen and falling ill would not be reduced.
- For the moment, studies carried out on this subject during the Covid-19 crisis have not been published.
With the Covid-19 epidemic, many gym or restaurant managers have installed air purifiers in their establishments. The objective was to protect customers from the virus to allow them to return to these places, where the risk of contamination – due to attendance – was high. But are these devices really effective?
You can get sick even with an air purifier
According to a new study published in the journal Preventive Medicine, air purifiers would not reduce the risk of getting sick. Indeed, according to researchers from the University of East Anglia (UEA), in England, they do not eliminate pathogens present in the air.
To reach this conclusion, scientists carried out a meta-analysis of studies published on this subject between 1970 and 2022. None were carried out during the Covid-19 health crisis because the results of those relating to this period do not have not yet been published.
“Air treatment technologies can be expensive, says Paul Huntermember, professor of the UEA Norwich Medical Schoolin a communicated. It is therefore necessary to measure the benefits against the costs and understand the current capabilities of these technologies.“The objective of the meta-analysis was therefore to measure the effectiveness of technologies – germicidal lamps, ionizers, air purifiers – to treat indoor air with the aim of preventing respiratory or gastrointestinal infections.
For this, the minimum criterion was that participants spent at least 20 hours per week in shared indoor spaces subject to air treatment strategies thought to modify the risk of infections or respiratory or gastrointestinal symptoms. The 32 studies chosen were all carried out in real contexts such as schools or retirement homes.
A high risk of contamination by a pathogen such as a virus
Results: in real conditions, scientists did not find evidence supporting the effectiveness of these devices on the risk of contamination. Thus, they believe that the risk of being infected by a pathogen, such as a virus, and of falling ill remains high even when these devices are installed.
“There was some weak evidence that air treatment methods reduced the risk of infection, but this evidence appears biased and unbalanced, concludes Dr Julii Brainard, researcher at UEA’s Norwich Medical School. We strongly suspect the existence of relevant studies with very minor or no effect, but these have never been published. Our results are disappointing. …but it is essential that public health decision-makers have a complete picture of the situation. I hope that the studies carried out during the [crise sanitaire de la] Covid-19 will be published soon and we will be able to make a more informed judgment on the value of air treatment during the pandemic.“