"In January this year, Covid-19 was officially designated a High Consequence Infectious Disease (HCID). The decision was made in consultation with a group of British experts.
A Health and Safety Executive evaluation of PPE published in 2019 had already recommended that all healthcare workers should wear a gown, FFP3 respirator mask and visor when dealing with HCIDs.
Those recommendations were in line with existing UK guidance.
But on 13 March this year, the government downgraded its guidance on PPE and told NHS staff they were safe to wear less protective aprons and basic surgical masks in all but the most high risk circumstances.
Panorama understands that on the same day, the government took steps to remove Covid-19 from the list of HCIDs.
But the experts who had recommended the coronavirus be put on the list in the first place were not consulted. Instead, the government asked its Advisory Committee on Dangerous Pathogens (ACDP).
Panorama has discovered that the ACDP was only asked to consider the matter on the morning of its 13 March meeting. It was added to the committee's agenda under "any other business".
The committee backed the decision to remove Covid-19 from the HCID list, but sources on that committee have told Panorama that it had to be, in part, a pragmatic decision based on the availability of PPE.
It was another six days before Public Health England announced that the coronavirus was no longer considered an HCID.
A governemnt spokesman said "we have taken the right steps at the right time to combat it, guided at all times by the best scientific advice.""