Covid-19: Doctors still at “considerable risk” from lack of PPE, BMA warnsBMJ 2020; 368 doi: https://doi.org/10.1136/bmj.m1316 (Published 31 March 2020) Cite this as: BMJ 2020;368:m1316
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Important practical and pragmatic safety measures for health care workers during covid-19 pandemic: The role and practicality of surgical face-masks
Important practical and pragmatic safety measures for health care workers during covid-19 pandemic: The role and practicality of surgical face-masks.
We are in unprecedented times with little high quality evidence regarding spread and prevention of covid-19 infection and hence critical thinking becomes all the more important. All the professional and media attention is almost wholly focussed on provision/scarcity of FFP3/N95 respirator-masks for health care workers (HCW). These are of course essential when looking after patients with suspected/diagnosed covid-19. But this is only part of the picture. It is estimated that 24-44% of new infections are caused by people before they become symptomatic.
Sergio Romagnani, a professor of clinical immunology at the University of Florence has reported that the great majority of infected people – 50 to 75% - were asymptomatic but represented “a formidable source” of contagion . Already two doctors have sadly died with covid-19 in the UK and there is no suggestion that they acquired the infection from patients diagnosed with covid-19. Several public figures have seemingly caught the virus simply by close proximity with pre-symptomatic people. It is not known whether these asymptomatic people were coughing and sneezing or contaminating fomites to any significant degree (unlikely). Importantly, it has been demonstrated that even normal tidal breathing releases aerosols of coarse and fine influenza viral particles and surgical masks provide significant barrier against these .
Hand washing is important and a recent review concluded that frequent hand washing reduces the infection by a third . But, face-masks also reduced the risk of infection by almost 50%  though not ‘statistically significant’ – tests of much controversy . The review concluded that given the questionable effectiveness of respiratory etiquette, mask use and hand hygiene should form the foundation of protective behaviour . Although the infection-risk may be low in routine clinical encounters, the consequences are high-risk with covid-19 compared to influenza. Both surgical masks and N95 respirators have been shown to be equally effective , although it’s assumed that the N95 are better. Do face-masks need to be close to 100% effective to be recommended--of course not!
Some of us have been adopters of fluid-resistant (Type IIR) surgical face-masks (cheap and widely available) during the routine hospital work as soon as the covid-19 epidemic started in the UK. Public Health England (PHE) and many hospitals have belatedly issued new guidance asking HCWs to wear fluid-resistant surgical masks with any close encounter with patients even in outpatient departments, which is very welcome. Most virologists accept that the ‘single use’ of surgical mask can extend up to a whole day session unless visibly soiled or a patient with suspected covid-19 is encountered. Surgeons have long experience of using face-masks. Other HCWs will quickly learn how and when to handle (remove and reapply) the mask if necessary with clean hands without ‘material’ risk of contamination. Hence, it seems unnecessary to change the masks between each or every few patients in view of the low background risk. Perfect is the enemy of the good (Voltaire). It would be prudent to avoid unnecessary depletion of masks given that many HCWs looking after the elderly (high-risk) occupants of nursing homes lack supply of masks, another matter of priority!
Conclusion: Several HCWs will catch covid-19 during this epidemic and many will have severe illness, including fatalities. PHE repeatedly asserts that the foremost weapon against covid is physical distancing (stay at home). For HCWs, close interaction with colleagues is unavoidable but seems no different from interaction with asymptomatic patients. A close prolonged/repeated contact with health-workers represents a significant potential infection-risk as the epidemic worsens. It would be advisable to extend practical safety precautions particularly wearing surgical face-masks to all HCW mutual interactions inside hospitals when safe physical distancing as advised by the WHO cannot be practised. This need not be absolute or preclude practicality and pragmatism.
Unfortunately, the experts have continued to hammer the message that “surgical face masks are not effective in prevention of infection”, by which they mean not very highly effective. The HCWs take their advice at its face value and underestimate the consequences of infection to themselves and continuing the chain of infection to others. There may be still time to limit the incidence of covid-19 in HCWs in hospitals in the UK.
Appendix: A leading WHO expert was grilled on BBC. She said, “We did not recommend use of surgical face-masks. But we also did ‘not not’ recommend surgical facemasks.” Some have claimed that the experts were misguiding the public to save the supply of masks for the health workers. But, a more benign explanation is probably right. When I had a telephone discussion with a leading microbiology expert, the difficulty was not about understanding good vs poor evidence. The struggle was to constantly separate ‘rational / logical’ statements from the otherwise. The flawed message was that as soon as a face-mask is worn, rigorous commandments (even if impractical) must be followed so that the ‘effectiveness’ of face-mask should not be dented even a bit. But at the same time it was all right not to wear a face-masks at all, because they are ‘ineffective’ anyway.
Conflict of interest: None to declare. The author has based this article on his long experience as a surgeon and the current observations in UK hospitals.
Dr Shashikant L Sholapurkar, MD, DNB, MRCOG
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Competing interests: No competing interests