There should be an "inquiry" into teachers infected with Covid because of a lack of emphasis from the government on transmission through poor ventilation, the editor of a prestigious medical journal has said.
And there now needs to be a "major investment" from the government in making schools "safe", according to Fiona Godlee, editor-in-chief of the British Medical Journal (BMJ).
Speaking to BBC Radio 4's Today programme this morning, Dr Godlee said an increased emphasis on aerosol spread – meaning transmission through airborne particles – had come "too late" for teachers infected with Covid through a "lack of adequate PPE [personal protective equipment]".
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She said there was a "real case to be answered there", and called for an inquiry into how the messaging on transmission had been handled by the government.
Dr Godlee was speaking as the BMJ published an editorial stating that "improving indoor ventilation and air quality will help us all to stay safe".
Covid: Government 'late in stressing the need for good ventilation in schools'
The authors argued that the virus causing Covid-19 "is mainly spread between people by breathing in airborne particles, droplets or smaller particles", she said.
"These aerosol particles are generated by...coughing and sneezing and singing, but also by talking and breathing, and they can remain in the air for hours if the air is not regularly refreshed – the smallest of these particles can stay airborne."
Dr Godlee said this means that, while people should still wash their hands, use face masks and keep their distance, "the most important precaution seems to be good ventilation" – such as circulating air, opening windows and doors, and being outside.
"It may be that this is indeed the most important thing we can do to prevent spread of Covid-19," she added.
Last month, the BMJ published an article warning that there was "insufficient emphasis" on classroom ventilation and mask-wearing in official guidance for keeping schools Covid-safe.
Asked about the government's communication of the science during the pandemic, Dr Godlee said an emphasis on aerosol spread had come "too late" for teachers who caught the virus owing to poor ventilation, and called for an inquiry into what happened.
"Well I think the messaging has been quite clear in many ways and this aerosol spread is something that has been gradually increasing as a message. But I do think that that's going to be important going forward," she said.
"And obviously looking back...the emphasis on aerosol spread has come too late for those people who were infected through lack of adequate PPE, you know, healthcare workers, teachers, etc.
"So I think there's a real case to be answered there and an inquiry into how the government handled it – from that point of view, I still think it's a very important piece."
She added: "Going forward, I think it's going to be clear messaging about opening the windows, opening the doors, meeting outside. And in the long term, there's a real need for proper investment in safe workspaces – so schools, hospitals and offices, and that's going to be a major investment for government and for the private sector."
The Department for Education said it had provided consistent advice to schools on ventilation since they first started to reopen last summer.
It added that it expects schools to provide good ventilation wherever possible, while maintaining a safe and comfortable environment for pupils and staff.