On wearing face masks, the public has been ahead of the experts

At the top of Government, there are fears about introducing any nuance into the Stay at Home message. The Cabinet wants to keep the directive simple. So it’s not very encouraging that on one of the simplest questions of all: “Should I wear a face mask?” the message is clear as mud.

A review is under way, Grant Shapps said yesterday. The Mayor of London, Sadiq Khan, isn’t waiting for that. He wants us to wear one. In Germany and America, face masks are now recommended. In other countries, they are compulsory.

While the intricacies of vaccine discovery or ventilator production are beyond the vast majority of us, the principle behind face masks isn’t. Coughed or sneezed droplets spread the disease. Yet, asymptomatic people spread it too.

The very best masks prevent wearers (usually doctors) from getting infected. But even simple surgical masks help prevent those carrying the virus from spreading it, which may be particularly useful since the non-appearance of any meaningful testing programme means we don’t know who has Covid-19, and very probably won’t for many moons to come.

So, given ample supply, surely it would be a good idea for us all to wear masks outside? Particularly as part of any exit strategy, given what we know about the immense effects of even minute adjustments in transmission rates.

Many health agencies, including our own, have disagreed. Yet, it turns out that they have largely based their views on a single source: the World Health Organisation. So, if the Government continued to trust that WHO advice, why the review? Should we be surprised if, as in America, having been nudged to assess the situation themselves, officials here change the advice too?

Perhaps the Government is maintaining its wait-and-see approach because, as with other protective gear, there are still not enough masks to go round. But that would make its “guided by the scientists” stance a deception.

If that stance is true, however, then it is worth remembering that those scientists the Government is guided by can make mistakes and be subject to bias like the rest of us.

On face masks, the public has been ahead of the game. But the pressure of “common sense” would have been useful even if it had been common “nonsense” – forcing a validation, rather than a change, of the existing advice.

This is not to say that we’ve had enough of experts. Far from it. In a time of immense crisis their work is vital. But the mask debate shows that we, too, have a duty, to deploy that age-old wisdom of crowds, whether right or wrong, to challenge and be annoying, and make those experts investigate not just the disease but their own assumptions too.

follow Harry de Quetteville on Twitter @harrydq; read More at telegraph.co.uk/opinion