Remember the COVID-19 pandemic? Sure you do, we all do! Did you research air filtration systems and purifiers during that time? Many providers did. They invested in what manufacturers touted as a way to decrease the spread of infectious respiratory diseases. If you did, good for you. We were all under a lot of stress, and devices were cropping up all over the place. However, recent research on air filters and respiratory infections suggests these devices may not make as much of a difference as we once hoped.

The problem is that researchers had rarely tested many of these devices in real-world situations. A recent study published in JAMA Network Open looked at portable air filtration in nursing homes. Medical Xpress also reported on the findings.

Researchers used HEPA (high-efficiency particulate air) filters, which remove more than 99.9% of very small particles from the air. This includes viruses. The trial included 91 nursing homes in the UK. Researchers placed HEPA filters in communal areas at 47 nursing homes. The other 44 nursing homes continued without them. Researchers then tracked respiratory infections among residents and staff. They also tracked staff illness and time off from work.

Unfortunately, the results showed no meaningful difference in infection rates, staff illness or absenteeism. The findings add another piece to the growing research surrounding air filters and respiratory infections. Previous research has also examined whether air-cleaning technologies reduce illness outside controlled laboratory settings. Studies published in PLOS Medicine and JAMA Network Open offer additional insight into air filtration and respiratory infection prevention.

Bottom line, filters alone may not make much difference. Much of the transmission of respiratory infections can happen at close range. A filter sitting in the corner of a room may not act quickly enough to prevent the spread.

If you have these devices in your community, maintain them properly. However, don’t depend on them alone to prevent the spread of infection. Continue appropriate infection control practices. These include handwashing, vaccines, isolation as needed, appropriate sanitizing solutions and housekeeping practices. Staff and resident education also remains important.

Stay well and stay informed!