key: cord-291392-19vj647z
authors: Poostchi, Ali; Kuet, Mong-Loon; Richardson, Patrick S.; Patel, Moneesh K.
title: Comment on: “Controversies regarding mask usage in ophthalmic units in the United Kingdom during the COVID-19 pandemic”
date: 2020-06-03
journal: Eye (Lond)
DOI: 10.1038/s41433-020-1005-y
sha: 
doc_id: 291392
cord_uid: 19vj647z

nan

We read with interest the article by Naveed et al. [1] on controversies regarding mask usage in ophthalmic units during the COVID-19 pandemic. We agree that offering patients a surgical face mask will lower the risk of them transmitting infection. We found that placing a mask in front of a breathing simulator led to a tenfold reduction in particle transmission [2] .

We would, however, question their assertions that UK guidance for Personal Protective Equipment (PPE) falls short and that FFP3 respirators should be mandated for dealing with symptomatic individuals. The WHO, CDC and ECDC recommend that respirators should be prioritised for use in high risk aerosol generating procedures and that surgical face masks are acceptable in other situations when treating individuals with suspected or confirmed COVID-19 [3] .

In addition, there is robust evidence from a large randomised control trial showing that in outpatients, there is no benefit from using N95 (FFP2) respirators compared with surgical face masks to reduce influenza and other respiratory viral illnesses in health care workers [4] . Subsequent meta-analyses have shown similar results with the benefits of respirators likely offset by discomfort with prolonged use leading to more frequent manipulation or reduced compliance [5] .

There is an added danger that using these respirators will lead to a false sense of security when in reality, PPE is only one part of an integrated approach to infection control.

Attention should also be given to measures such as streamlined patient flow and scrupulous disinfection which are further up in the 'hierarchy of control'.

Conflict of interest The authors declare that they have no conflict of interest.

Publisher's note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Controversies regarding mask usage in ophthalmic units in the United Kingdom during the COVID-19 pandemic

Efficacy of slit lamp breath shields

Airborne or droplet precautions for health workers treating COVID-19? J Infectious Dis

N95 respirators vs medical masks for preventing influenza among health care personnel: a randomized clinical trial

Effectiveness of N95 respirators versus surgical masks against influenza: a systematic review and meta-analysis