Wash your mask daily: the ultimate guide to face coverings

We hook them on to our faces, laugh, sneeze and sputter into them, then crumple them into our bags or pockets only to retrieve them and do it all again. Yet despite official advice that we should be wearing a fresh face covering each time we enter an enclosed public space, a YouGov poll revealed many people are going several wears between washes – and 15% of Brits don’t wash their reusable masks at all. Similarly, more than half of those opting for disposable masks are rewearing them – 7% of them indefinitely so.

Face coverings are designed to catch the respiratory droplets we emit from our mouths and noses, but given that they’re our own respiratory droplets, is this really so bad? We examine the evidence.

How contaminated do face masks get, and with what sorts of microbes?

If you were to swab your used face covering and grow the microorganisms in a petri dish, you would find a variety of bacteria, viruses and fungi. “Most are likely to be harmless – you would get something similar if you sampled your hands, nose, mouth or many other parts of your body,” says Prof Cath Noakes, an expert in airborne disease transmission at the University of Leeds. However, combined with the friction and humidity associated with prolonged mask-wearing, this microbial menagerie could trigger outbreaks of “maskne”.

Maskne: what is it?

Maskne is an umbrella term coined to cover all manner of facial rashes associated with mask-wearing including acne, says Dr Thivi Maruthappu, a consultant dermatologist at Highgate hospital and spokesperson for the British Skin Foundation. “As masks can be a vector for bacteria, fungi and viruses, I would recommend washing your mask on a daily basis if you’re wearing it every day.” Soft fabrics such as cotton are less likely to cause friction than synthetic fibres like polyester, she adds.

What’s the risk of catching Covid-19 from a dirty mask?

If you had Covid-19, then your face covering would be heavily contaminated with coronavirus, as well as other bugs. Your mask would pose a risk to others if they handled it, so you should never share masks or touch someone else’s without thoroughly washing your hands.

Other people’s exhalations are a different matter. A 2019 study of healthcare workers identified various respiratory viruses on the outside of their masks, including influenza and adenovirus, a cause of the common cold. Although there is currently no data proving that such external contamination increases Covid-19 risk, “it theoretically could if you touched the mask and then touched your nose or eyes,” says Noakes.