Should we all be wearing face masks again?

Covid is back in the news again as a fresh wave has sent cases soaring across the UK in recent weeks.

The dominance of new Covid variants BA.4 and BA.5 in the UK suggest they're either more transmissible or better at evading immunity - or both.

Mask wearing had largely dropped off once rules were scrapped, but there's increasingly an argument for reintroducing them in certain situations as infections rise rapidly again.

Some GP surgeries and hospitals have already taken this step, encouraging all staff to wear face masks, as well as asking patients to do so.

So is it worth digging out your face mask and what kind should you be wearing? We look at the options.

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Are reusable face coverings good enough?

With the increased transmissibility of Omicron, people started choosing higher-spec disposable face masks such as FFP (filtering face piece) respirators due to the more stringent standards on filtration these masks have to adhere to.

Indeed, there's a line of argument in scientific and medical circles that, due to how easily Omicron spreads, these masks are the only ones that will do. 

This is because FFPs (roughly equivalent to N95, or KN95 masks) are designed to protect the wearer from breathing particles in, as well as filtering exhalations, so they offer more protection in higher-risk situations.

They also have to conform to specific standards of filtration - above 94% for an FFP2 and above 99% for an FFP3. This becomes particularly important when wider mask wearing and isolation measures have dropped off as there's more chance you'll be exposed to the virus.

However, FFP's aren't foolproof (good fit is key) and there are some high-filtration reusable and semi-reusable masks that provide a good level of filtration too.

Our reusable face covering tests found some which filtered 99.9% of tiny particles before washing and 94% after five washes.

So, depending on your level of risk and where you need to wear it, a reusable mask can still be an eco-friendly and cost-effective option. 

Even so, disposable respirators are worth considering for more vulnerable people, and for higher-risk encounters such as where you are in an enclosed crowded space for longer periods of time.

Is there any point wearing a face mask when others aren't?

Despite the rise in cases and reinfections, face coverings are still a relatively rare sight. But there are benefits to wearing a mask even if others around you aren't.

Properly fitted, high-filtration masks can offer protection to the wearer. They are particularly good for people more vulnerable to Covid and at greater risk of severe disease, especially in crowded environments at times of high infection rates. 

Wearing a high filtration mask will lessen the amount of virus you breathe in if you are exposed, which typically means getting milder illness.

For some, it's about cutting the risks where possible - for example wearing a mask on a crowded train, even if you are going out to dinner. 

As ever, it's about being practical about what works for you, with the needs of more vulnerable people in mind as well. 

Find out more about choosing the best disposable mask in our disposable mask buying guide. 

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New reusable face coverings tested: top picks and which to avoid

We've recently tested 10 more reusable face coverings and found some good options, including a new Best Buy and a Great Value mask, both with high filtration. 

But we also uncovered two masks which failed our filtration tests, despite making big claims about effectiveness.

Best new face masks

• Best Buy - Marca Disati Reusable Protection Mask (£10 for three / £3.33 per mask), available from Etsy. Filters 93.8% of tiny particles both on first use and after five washes.
• Great Value - Uniqlo AIRism Mask (£2.90 for three / 96p per mask) available from Uniqlo. Filters 99.5% of particles when new, and still achieving 96.9% after five washes.

Face coverings to avoid

• Don't Buy - Maskari Advanced Pro mask - only filtered 47.1% of particles on first use, increasing to a still-low score of 58.7% after washing.
• Don't Buy - ViroMasks Shield - filtered only 47.9% on first use, dropping to 40.2% after five washes. 

Both these masks did poorly in our filtration tests. They claim enhanced protection by using antimicrobial chemical treatments on their fabric, the effects of which our tests don't measure. 

However, it's worth noting that there have been some concerns around the potential health hazards of chemically treated masks in general, when you can achieve high levels of protection with a well-fitting, high filtration mask. 

Maskari told us: 'Maskari masks have been tested by Swiss Labs and approved as a community mask in Switzerland with good filtration results so we are surprised by the Which? results. Also, our masks have three layers and each layer has an Intelligent Swiss Technology by HeiQ, the middle layer has an antimicrobial technology and Which? tests do not take this into account.'

Viromasks said the Shield should be tested under the standard for antiviral textiles, not the standard for face masks, as it uses chemical textile treatment rather than high-filtration materials to block particles. Viromasks provided Which? with a test it had commissioned to show the efficacy of its antimicrobial fabric against the influenza virus and feline calcivirus. 

See the full results in our face covering reviews.