At last, health, aged care and quarantine workers get the right masks to protect against airborne coronavirus

Almost a year ago, in July 2020, our calls^[1] for the government to urgently upgrade the guidelines to protect health workers from airborne SARS-CoV-2 fell on deaf ears.

The existing guidelines said health providers working around COVID-19 patients should wear a surgical mask. It restricted use of the more protective P2 or N95 masks^[2], which stop airborne particles getting through, to very limited scenarios. These involved “aerosol-generating procedures”, such as inserting a breathing tube. This was expanded slightly in August 2020 but still left most health workers without access to P2/N95 masks.

More than 4,000^[3] Australian health workers were infected by COVID-19 during the Victorian second wave. Health authorities denied the importance of airborne transmission and blamed^[4] clinical staff for “poor habits” and “apathy”. Health workers expressed despair and a sense of abandonment^[5], cataloguing the opposition they faced to get adequate protection against COVID-19.

Last week, 15 months after the COVID-19 pandemic was declared, the Australian guidelines^[6] on personal protective equipment (PPE) for health workers, including masks, were finally revised.

What do the new guidelines say?

The new guidelines expand the range of situations in which P2/N95 masks should be available to staff – essentially anywhere where COVID-19-infected people are expected to be – and remove all references to “aerosol-generating procedures”.

This recognises that breathing, speaking, sneezing and coughing all generate aerosols^[7] which can accumulate in indoor spaces, posing a higher risk^[8] than “aerosol-generating procedures”.

Read more: Which mask works best? We filmed people coughing and sneezing to find out^[9]

“Fit testing” is an annual procedure^[10] that should be done for all workers wearing a P2/N95 mask or higher grade respirator, to ensure air can’t leak around the edges.

But this was previously denied to many^[11] Australian health workers.

The new guidelines unequivocally state fit-tested P2/N95 masks are required for all staff managing patients with suspected or confirmed COVID-19. This means health workers can finally receive similar levels of respiratory protection^[12] to workers on mining and construction sites.

The new guidelines leave ambiguity around which workplaces are within the scope by stating that health care:

may include hospitals, non-inpatient settings, managed quarantine, residential care facilities, COVID-19 testing clinics, in-home care and other environments where clinical care is provided.

The guidelines also allow employers to decide what comprises a high risk and what doesn’t, allowing more wiggle room to deny workers a P2/N95 mask.

The guidelines say when a suitable P2/N95 mask can’t be used, a re-usable respirator (powered air purifying respirators, or PAPRs) should be considered.

But the guideline’s claim that a PAPR may not provide any additional protection compared to a “well-sealed” disposable P2/N95 mask, is not accurate. In fact, re-usable respirators such as PAPRs afford a higher level of protection^[14] than disposable N95 masks.

The new guidelines should also apply to workers in hotel quarantine – both health care and non-clinical staff. This will help strengthen our biosecurity, as long as they’re interpreted in the most precautionary way.

That means not using the wiggle room that allows workplaces to deem a situation lower risk than it actually is or that their workplace is exempt. When working around a suspected or confirmed COVID-19 case, all workers must be provided with a fit-tested P2/N95 mask. Otherwise they are not protected from inhaling SARS-CoV-2 from the air.

In aged care and health care, where cases linked to quarantine breaches can be amplified and re-seeded to the community, the new guidelines go some way towards better protecting our essential first responders and their patients.

Read more: What's the Delta COVID variant found in Melbourne? Is it more infectious and does it spread more in kids? A virologist explains^[15]

Guidelines miss the mark on ventilation

The guidelines fail to explicitly acknowledge COVID-19 spreads through air^[16] but nonetheless recommend the use of airborne precautions for staff.

Airborne particles are usually less than 100 microns^[17] in diameter and can accumulate indoors, which means they’re an inhalation risk.

The old guidelines focused on “large droplets”, which were thought to fall quickly to the ground and didn’t pose a risk in breathed air. This was based on debunked theories^[18] about airborne versus droplet transmission.

The new guidelines fail to comprehensively address ventilation, which is only mentioned in passing with a reference to separate guidelines for health-care facilities^[19]. This may not cover aged care or hotel quarantine.

Read more: This is how we should build and staff Victoria's new quarantine facility, say two infection control experts^[20]

We must ensure institutions such as hospitals, hotel quarantine facilities, residential care, schools, businesses and public transport have plans to mitigate the airborne risk of COVID-19 and other pandemic viruses through improved ventilation and air filtration.

Australia could follow Germany^[21], which has invested €500 million (A$787 million) in improving ventilation in indoor spaces.

Meanwhile, Belgium is mandating the use of carbon dioxide monitors^[22] in public spaces such as restaurants and gyms so customers can assess whether the ventilation is adequate.

Cleaning shared air would add an additional layer of protection beyond vaccination and mask-wearing. Secondary benefits^[23] include decreased transmission of other respiratory viruses and improved productivity^[24] due to higher attention and concentration levels.

No updated advice on hand-washing

The United States Centers for Disease Control and Prevention (CDC) now acknowledges^[25] exposure to SARS-CoV-2 occurs through “very fine respiratory droplets and aerosol particles” and states the risk of transmission^[26] through touching surfaces is “low”.

Yet this is not acknowledged in the latest Australian health-care guidelines.

Australians have been repeatedly reminded to wash or sanitise their hands, wipe down surfaces and stand behind near-useless plexiglass barriers^[27].

The promotion of hand hygiene and cleaning surfaces is not based on science^[28], which shows it is the air we breathe that matters most.

Revised public messaging is needed for Australians to understand shared air is the most important risk for COVID-19.

References

1. ^{^} our calls (www.mja.com.au)
2. ^{^} P2 or N95 masks (www.cdc.gov)
3. ^{^} More than 4,000 (www.coronavirus.vic.gov.au)
4. ^{^} blamed (www.theaustralian.com.au)
5. ^{^} expressed despair and a sense of abandonment (bmjleader.bmj.com)
6. ^{^} Australian guidelines (www.health.gov.au)
7. ^{^} generate aerosols (theconversation.com)
8. ^{^} higher risk (associationofanaesthetists-publications.onlinelibrary.wiley.com)
9. ^{^} Which mask works best? We filmed people coughing and sneezing to find out (theconversation.com)
10. ^{^} annual procedure (www.mja.com.au)
11. ^{^} previously denied to many (bmjleader.bmj.com)
12. ^{^} similar levels of respiratory protection (covid19evidence.net.au)
13. ^{^} Shutterstock (www.shutterstock.com)
14. ^{^} higher level of protection (www.osha.gov)
15. ^{^} What's the Delta COVID variant found in Melbourne? Is it more infectious and does it spread more in kids? A virologist explains (theconversation.com)
16. ^{^} spreads through air (theconversation.com)
17. ^{^} usually less than 100 microns (science.sciencemag.org)
18. ^{^} debunked theories (www.wired.com)
19. ^{^} health-care facilities (healthfacilityguidelines.com.au)
20. ^{^} This is how we should build and staff Victoria's new quarantine facility, say two infection control experts (theconversation.com)
21. ^{^} Germany (www.bbc.com)
22. ^{^} mandating the use of carbon dioxide monitors (twitter.com)
23. ^{^} Secondary benefits (science.sciencemag.org)
24. ^{^} improved productivity (www.hup.harvard.edu)
25. ^{^} now acknowledges (www.cdc.gov)
26. ^{^} risk of transmission (www.cdc.gov)
27. ^{^} plexiglass barriers (reason.com)
28. ^{^} not based on science (www.nature.com)