More and more adults in their 30s and 40s are choosing to wear face masks on buses and trains amid spiralling Covid cases, official data suggests.
An Office for National Statistics (ONS) poll revealed 33 per cent of middle-aged adults wore coverings while on public transport at the start of September, just after schools went back.
But just a month later this had ticked upwards to almost 40 per cent, despite no change in official guidance.
A similar rise in face mask use on public transport was also seen among 50 to 69-year-olds towards the end of September, while it remained constant among the over-70s. For young adults use of the coverings dropped towards the end of September.
Face mask use has risen since January because the figures are based on people saying whether they wore a face mask on public transport, and not everyone used buses at the height of the second wave in January.
Dr Raghib Ali, a statistician at Cambridge University, said it was to be expected that face mask use on buses and trains would rise as Covid cases headed north.
He told MailOnline: 'People tend to change their behaviour when Covid cases go up. We saw that in July as well, and we are heading to a similar level of cases at the moment.'
Britain yesterday recorded another 49,139 Covid cases. Health Secretary Sajid Javid warned infections may breach 100,000 within weeks.
The above graph reveals face mask use on public transport. It shows how it has risen among 30 to 49-year-olds since September, when schools went back leading many adults to also return to the office. The lines show the percentage of people who said they wore face masks on public transport, out of those who said they had worn a face mask in the week before they were questioned. The data is from a survey by the Office for National Statistics
Boris Johnson made coverings optional in England on Freedom Day in July, despite No10's top scientists urging them to be kept mandatory. They are still in use in Scotland, Wales and Northern Ireland.
The Prime Minister is now facing mounting pressure from unions and doctors to make the masks mandatory again and re-impose work from home guidance to help head off rising cases.
Face masks help stop the spread of the coronavirus by catching miniscule droplets exhaled by infected people. But the science on how well they work has been patchy, although experts insist the benefits of wearing coverings are obvious.
The ONS survey — titled 'Coronavirus and the social impacts on Great