The quality of face masks healthcare workers wear makes a huge difference to their risk of coronavirus infection, Cambridge University Hospitals NHS Foundation Trust research has found.Wearing a high grade mask known as an FFP3 can provide up to 100% protection.
By contrast, there is a far greater chance of staff wearing standard issue surgical masks catching the virus.
Professional bodies have long campaigned for staff to be given better personal protective equipment.
The data was gathered during a programme of regular testing for Covid at the trust.
The results are published in a pre-print paper that has not been peer-reviewed.
For most of last year, the hospital followed national guidance which specifies that healthcare workers should wear surgical masks, except in a few limited situations.Though fluid resistant, these masks are relatively flimsy and loose-fitting and are not meant to screen out infectious aerosols - tiny virus particles that can linger in the air and are now widely accepted as a source of coronavirus infection.
The study found that staff caring for Covid patients on "red" wards faced a risk that was up to 47 times higher than those on "green" or non-Covid wards.