Hundreds of medical professionals have appealed for higher-grade personal protective equipment (PPE) amid growing concern over airborne transmission of coronavirus.

In an open letter to political leaders, doctors, nurses and consultants say healthcare workers on the general wards are about twice as likely to contract Covid-19 than intensive care unit staff, who have the best equipment.

They suggest this is down to increased aerosol protection given by higher-grade PPE and better ventilation in intensive care units.

The Royal College of Nursing backed the appeal, calling for a review of the existing PPE guidance and ventilation in hospitals “without delay”.

How much virus transmission takes place by aerosols – small droplets which can linger in the air for hours – is still not known.

World Health Organisation (WHO) guidelines focus on the virus being spread primarily through larger droplets from the nose or mouth from coughing, sneezing and speaking, but it has acknowledged “emerging evidence” that Covid-19 could be spread through particles in the air.

Current UK Infection Prevention Control (IPC) guidance on the type of PPE used centres on whether a procedure is deemed to be “aerosol generating” or “non-aerosol generating”.

But the letter states: “This is no longer compatible with what we now know.”

Dr Chaand Nagpaul, British Medical Association (BMA) council chair, said: “With the new, more transmissible virus, it is a duty of the NHS to provide healthcare staff with the necessary protection against this more contagious strain.

“Staff are going off sick with Covid-19 symptoms and unable to help patients, and at a time when the NHS is facing overwhelming demand, this is adding significant pressure to the system.

“We raised this issue of revising the PPE requirements for healthcare staff in light of the new variant virus with Government before Christmas.

“We desperately need answers as soon as possible, not only to keep our workforce safe, but also our patients and the overall functioning of the NHS.”

The group delivering the appeal is Fresh Air NHS, which describes itself as “a group of frontline healthcare workers and supporters who recognise the importance of airborne SARS Co-V 2.”

It called for all staff working with confirmed or suspected Covid-19 patients to have access to a more advanced FFP3 mask, which contains an air filter, a review of PPE guidance, and for hospitals to maximise natural ventilation.

The letter states: “We implore that these recommendations are implemented across the UK as soon as possible. Mass vaccination and its impacts on rates of transmission will take time to take effect.

“It is therefore imperative to maximise science-based preventative measures towards aerosol/airborne transmission in addition to standard droplet precautions in healthcare settings now.”

Dr Yvonne Doyle, medical director at Public Health England (PHE), said: “The NHS Infection Prevention Control group has reviewed the latest evidence and has advised that PPE should continue to be worn as laid out in the current IPC guidance, with FFP3 masks required for staff undertaking clinical aerosol generating procedures. This is supported by WHO.

“Emerging evidence and data on variant strains and transmission will be continually monitored and reviewed.”

The Scientific Advisory Group for Emergencies (Sage) has found no evidence of any association between the new variant and increases in transmission in particular settings, like hospitals.

Dame Donna Kinnair, chief executive of the Royal College of Nursing (RCN), for staff working with suspected or confirmed Covid-19 cases to be given higher-level PPE and called for a review “of the effectiveness of ventilation in health and care buildings”.

A Department of Health and Social Care spokeswoman said: “The safety of NHS and social care staff has always been our top priority and we continue to work tirelessly to deliver PPE to protect those on the frontline.

“UK guidance on the safest levels of PPE is written by experts and agreed by all four chief medical officers. The guidance is kept under constant review based on the latest evidence and data.”

The open letter can be found here: https://drive.google.com/file/d/1DlqkIAHD5PLCAlOKyNRWsblhlwVS8FqK