Sir,
I would like to make several comments on the letter by Puro et al.1 In their letter, references 6 and 7 should be reversed. As they note, I recommend, as indicated in their reference 7, that a level of respiratory protection above N95 should be employed to protect healthcare workers (HCWs) against airborne transmission of the severe acute respiratory syndrome coronavirus (SARS CoV) as well as other communicable diseases, including those that can be considered to be emerging (e.g. avian influenza—H5N1).2, 3 In their letter, they also address the question of the airborne transmission of SARS. It should be noted that current evidence supports the transmission of SARS CoV by an airborne route, which includes both environmental and occupational settings.4, 5, 6 It has been suggested that during aerosolization, some particles dry out (desiccation) and remain infective.3 An airborne route of exposure demonstrates the importance of respirators (see reference 2 for a recent review on respirators and SARS). The SARS event(s) shows the critical nature of proper personal protective equipment for HCWs, especially during the occurrence of an emerging infectious disease.
References
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