Mask mania is a curious thing.  Not only does it appear to be based on a dubious reading of the available scientific evidence, it has now taken on an almost ritualistic aspect in our public debate about coronavirus.

During the height of the Covid-19 epidemic in March and April, masks were entirely optional. In fact, they were positively discouraged – untrained amateurs, we were told, should not wrap a moist, bacteria-infested rag around our faces: leave this to the experts. They use proper kit, are trained in how to use them, and are doing so in the course of their work, we were told. Yet decades of peer-reviewed research (including randomised trials with control groups) have failed to prove unequivocally that their use has a material impact on the spread of airborne viruses.

Despite all this – ping – the mask mandates appeared mid-June, and have intensified since. Let us be clear – these are not for our own good.  Oxfordshire County Council, for example, in its guidance for producers of face coverings, states that health claims such as “Keeps you safe” or “Protects you from viruses” must be avoided.

Now we are told these are for the benefit of others: “The best available scientific evidence is that, when used correctly, wearing a face covering may reduce the spread of coronavirus droplets in certain circumstances, helping to protect others,” the official government guidance reads.  There is clearly an absurdity here. Do people realise how small “coronavirus droplets” are? Put it this way: you’re going to have more luck stopping mosquitoes with chicken wire. Just observe how a vaper’s exhaled breath (i.e. steam) quickly spreads.

And while we live in a free country, masks are of course now the law.  Despite, of course, the fact that a certain Boris Johnson got embroiled in a fierce argument in 2018 for stating that “businesses and government agencies should be able to ‘enforce a dress code’ that allowed them to see customers’ faces.” Oh how times have changed.

How on earth did this volte face (or, more accurately, hidden face) come about? Have the facts changed?

A supposedly important meta-study into this question was conducted by the Lancet and published in early June 2020.  A meta-study is research that pulls together multiple other previously published datasets and peer-reviewed papers (i.e. the decades of research that have been unable to show an overall net benefit for general use).  None of the observational studies chosen for the meta-study included any randomised controlled trials. The best they could come up with was a low confidence that face masks could result in a large reduction in infections. And it seems to me that many unproven assumptions were made in coming to this nondescript conclusion.

This research was funded by the World Health Organisation (WHO), an outfit that has had its fair share of “about face” moments during this pandemic. Well, this is the same WHO that recently publicly endorsed Sweden’s approach to the pandemic, and who recently appointed Sweden’s former state epidemiologist Johan Giesecke as the Deputy Chair of the WHO’s Strategic and Technical Advisory Group. Well, there have been no face mask mandates in Sweden, and usage there is low. Like the UK, Sweden made mistakes in handling the virus spread in care homes early during the outbreak, but they have substantially minimised the overall negative impact and social harm of their counter-Covid19 measures.

Moving on from the low confidence possibilities, the Lancet meta-study unequivocally stated: “most stakeholders… noted harms and contextual challenges, including frequent discomfort and facial skin breakdown, high resource use linked with the potential to decrease equity, increased difficulty communicating clearly, and perceived reduced empathy of care providers by those they were caring for.”

Urgh. So definite cons for the individual and social groups, yet no guaranteed pros for the community. In my mind the key failing here, though, is the lack of inclusion of randomised trials in the meta-study.

That is because these are unambiguous in their scepticism about the efficacy of mask wearing. Take this example from a group of French researchers: “In various sensitivity analyses, we did not identify any trend in the results suggesting effectiveness of facemasks.”

Or read this brutal summary from the Center for Infectious Disease Research and Policy at the University of Minnesota: “We continue to conclude that cloth masks and face coverings are likely to have limited impact on lowering COVID-19 transmission, because they have minimal ability to prevent the emission of small particles, offer limited personal protection with respect to small particle inhalation, and should not be recommended as a replacement for physical distancing or reducing time in enclosed spaces with many potentially infectious people.”

The same authors conclude that: “Sweeping mask recommendations—as many have proposed—will not reduce SARS-CoV-2 transmission, as evidenced by the widespread practice of wearing such masks in Hubei province, China, before and during its mass COVID-19 transmission experience earlier this year. Our review of relevant studies indicates that cloth masks will be ineffective at preventing SARS-CoV-2 transmission, whether worn as source control or as PPE.”

This last quote may sound like the grumpy ranting of a dyed-in-the-wool cranky surgeon, but a recent seroprevalence study shows that Covid-19 ripped through Tokyo over the summer despite mask wearing, social distancing and “world class” track & trace. So it seems that Mr Cranky Surgeon has a point.

If I carry on quoting articles and peer-reviewed papers, I’ll run out of original words to write. But this really is “the science”.  Decades of research have not managed to prove unequivocally either way that masks help.

At the same time, what we do know is that facemasks can have significant downsides that have been clinically proven. A paper published in 2015 reported on a randomised clinical trial by researchers at the University of New South Wales who found that respiratory infection is much higher among healthcare workers wearing cloth masks compared to medical masks.  Even if you are “lucky” enough to be using medical-grade masks will find that you are breathing in more CO2 than you should be (not in a climate-change way, but in the “O2 in, CO2 out” way that our lungs are supposed to work – too much “CO2 in” is not ideal for people that have breathing difficulties such as asthma, COPD, hay fever).

Masks can also disorientate older, less mobile people; they can cause falls when impeding vision. In short, they are potentially causing a lot of problems, and if we are going to “follow the science” – as we have been repeated informed we are doing – then in the absence of unequivocal evidence to the contrary about their net benefits, they should be optional only.

Because here’s the rub. If it turns out that they are a placebo, or just a mass hysterical over-reaction, what of the kids? The lonely? Those we were supposed to reach out to, look after and nurture? What of the grandparents that spent a crucial year of their lives behind a mask? What of the psychological aspects? Thankfully, the concept of consent has been covered exhaustively in recent years to the extent that it is a broadly accepted principle, and it should apply here too.

In this country we seem to have steered clear of masking up younger children, but if it turns out that authorities didn’t “follow the science” when mandating mask wearing, then how is the legally-enforced muzzling of vulnerable citizens – young and old – possibly justified? This thought alone should make everyone think very hard about the checks & balances needed to avoid panic-driven law-making in future.

Because here is another thing.  What if masks are in fact interrupting the normal transmission of bugs – the “healthy” way that humans interact socially so as to build up community immunity for the uncountable number of circulating bacteria and viruses?  What if we are upsetting this delicate balance with a one-sided “war on Covid-19”?

The danger here is that we are weakening our immune systems with this massive experiment, and potentially causing a serious spike in outbreaks of either the next coronavirus or other diseases at some point in the near future. Despite looking high and low, I have not seen the ethics approval paperwork that would normally be associated with such a study on a small scale, let alone for what is turning out to be a lawfully-mandated worldwide experiment.

Britain should keep these masks optional, and focus instead on measures that are sustainable and in proportion, which avoid collateral social harm. I’ll leave the last word to Professor Carl Heneghan of the Centre for Evidence-Based Medicine at Oxford University:

“We consider it is unwise to infer causation based on regional geographical observations as several proponents of masks have done. Spikes in cases can easily refute correlations, compliance with masks and other measures is often variable, and confounders [causes of spurious association] cannot be accounted for in such observational research.”

What the country needs as we enter the winter is rational policy, not coronavirus-fuelled panic.

Dr Alex Starling is an advisor to and non-executive director of various early-stage technology companies.