The number of people wearing face masks in Wales has taken a nosedive in recent weeks, according to the latest Government study.
In fact, fewer people in Wales are wearing face masks now compared to England, where it's not even compulsory to wear one at all.
The study comes as Wales' Chief Medical Officer (CMO) Dr Frank Atherton has warned that people need to continue following current Covid rules or stricter measures could be brought in.
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People in Wales have been fairly consistent in wearing masks since September, 2020, just before the country introduced the fire-break lockdown. Uptake on mask wearing was much quicker among the English and Scottish populations.
But the latest data shows that the proportion of adults wearing a face mask in England has dropped off relatively consistently since mid-July, the so-called 'Freedom day'. And in Wales, the proportion of adults wearing a face mask has declined steeply in the past four weeks, so much so that fewer people are now wearing masks than across the border.
In England, the legal requirement to wear a face covering ended on July 19, apart from in healthcare settings and care homes, unless exempt. However, the Health Secretary has warned that if the NHS struggles to cope this winter, then face coverings could be mandated again in certain situations in England.
In Wales, masks are still legally required on public transport and in all public indoor areas apart from pubs and restaurants.
And in Scotland, masks must still be worn in shops and on public transport - as well as in pubs and restaurants when not seated. They are required in indoor public spaces in universities and remain compulsory for all school staff as well as secondary school pupils.
The data shows that across all three nations, the biggest decline in mask-wearing is among those aged under-60.
The figures for the seven-day period up to October 6, are taken from the latest CoMix study, a behavioural study launched by the UK government in March, 2020. The sample is broadly representative of the UK adult population and participants are invited to respond to the survey once every two weeks.
Last week, the CoMix findings reported that people in England were less likely to report wearing face coverings ( less than 70%) than those from Wales or Scotland (85% or more). The data this week suggests a sharp decline in reported face-covering use for participants from Wales which is now consistent with England at below 70%.
However, it must be noted that this change could be due to a small sample size from Wales with associated variability in reporting.
Dr Atherton, who advises the Welsh Government on its Covid response and attends many of the key Sage meetings involving scientists and medical professionals, told BBC Wales Breakfast on Monday: "A very significant proportion of the Welsh population is still behaving with extreme caution and realises that we are not out of the woods with this yet, but there is a sense in other places that it is all over.
"When we see people not using face coverings, even though it's a legal requirement to do so, that worries me. When we see people crowding into taxis - as I saw down in Cardiff Bay last night - without face coverings and not being challenged, that worries me. When I see leisure centres which are overcrowded and people not social distancing, that really worries me."
One of the key measures being considered to halt soaring infection rates in Wales is how to get more people to wear face coverings indoors. Health minister Eluned Morgan confirmed she was looking at three key restrictions ahead of the next Welsh Government three-weekly review.
Mrs Morgan said: "We will be looking to see how we can absolutely make the most out of the measures that we already have in place.
"Is there anything more we can do for example, around working from home, which we know makes a huge difference? Is there more we can do to make sure that people actually do wear their face coverings, in public places indoors? And we'll be seeing if it may be necessary for us to roll out the vaccine passports to other situations."
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