key: cord-0070562-2ph8r24c authors: Brooks, John K.; Sultan, Ahmed S.; Jabra-Rizk, Mary Ann title: PROLONGED FACIAL MASK WEAR IS A CONCERN FOR THE DEVELOPMENT OF DYSBIOTIC MICROBIOME date: 2021-11-27 journal: Respir Med Res DOI: 10.1016/j.resmer.2021.100877 sha: 2d708e7c58a1a85367a86a3c17431a42812a9ba3 doc_id: 70562 cord_uid: 2ph8r24c nan A diversity of dermatopathologies has been attributed to occlusive seal of the face mask in the setting of a closed warm moist milieu, local microbiome, and chemical irritants contained within the mask material [1] . Face masks worn for at least 6 hours per day have resulted in allergic and irritant contact dermatitis, acneiform eruptions, atopy and seborrhoeic eczema, periorificial dermatitis, urticaria, rosacea, folliculitis, and pruritus [1] [2] [3] . Further, a hospitalized patient, admitted for acute myocardial infarction, developed a facial herpetic simplex infection through autoinoculation from use of an intubation mask [4] . In a somewhat analogous context, numerous investigations have substantiated that extended use of various medical devices (tracheal intubation, mechanical ventilation, indwelling catheters) has been associated with Staphylococcus aureus, S. haemolyticus, enterococcus, Pseudomonas aeruginosa, Klebsiella pneumoniae, and candida albicans [5] . Additionally, chronic denture wearing during sleep among the elderly may lead to pneumonia consequent to the overgrowth of oral mucosal candidiasis promoted by the underlying denture microenvironment [6] . However, there is a paucity of published information whether prolonged facial coverings play any putative role in nondermatologic disorders. Ahmad et al. investigated the traditional wearing of niqabs (facial cloth veils) and found statistically increased incidences of the common cold and asthma among wearers versus non-veil wearers [7] . There was also an increased frequency of tuberculosis among veil wearers but the overall reduced number of incident cases precluded statistical inference. It is less clear how many hours or days that nonhealthcare individuals wear the same unsanitized face mask and whether exhaled, nasal, cutaneous, oral, oropharyngeal, and gastrointestinal organisms cultivated on the underside of the mask promote dysbiotic microbiomes and host illness. Another potential source of the inner mask biome is through contamination of viral carriages (adenovirus, bocavirus, influenza) and bacterial colony-forming units from other individuals via the incomplete protection afforded by some commercial and noncommercial grade face mask products [8, 9] . Occupational dermatitis to facial personal protective equipment in health care workers: a systematic review Mask related acne ("maskne") and other facial dermatoses COVID-19 related masks increase severity of both acne (maskne) and rosacea (mask rosacea): multi-center, real-life, telemedical, and observational prospective study Facial herpes simplex: autoinoculation by an intubation mask Analysis of pathogens and risk factors of secondary pulmonary infection in patients with COVID-19 Denture wearing during sleep doubles the risk of pneumonia in the very elderly The effect of wearing the veil by Saudi ladies on the occurrence of respiratory diseases Contamination by respiratory viruses on outer surface of medical masks used by hospital healthcare workers Contamination of surgical mask during aerosol-producing dental treatments John K. Brooks ID http://orcid.org/0000-0001-6634-8470 Ahmed S. Sultan ID https://orcid.org/0000-0001-5286-4562 Mary Ann Jabra-Rizk ID https://orcid.org/0000-0002-4425-3873The authors declare that they have no competing interests. All authors read and approved the final manuscript. Clinically controlled studies are advocated to characterize and quantify the microbial colonies along the underside of the face mask, the pathophysiologic mechanisms and chronology for the development of a dysbiotic microbiome, ascertain the incidence of autoinoculation of microbial colonies residing under the face mask, and to determine the potential local and systemic consequences of prolonged mask wear within nonhealthcare subpopulations. Not applicable.