Revista de Odontologia da UNESP
https://revodontolunesp.com.br/article/doi/10.1590/1807-2577.20260008
Revista de Odontologia da UNESP
Original Article

Microbiological contamination in surgical masks used by students in an emergency hospital: cross-sectional study

Contaminação microbiológica em máscaras cirúrgicas utilizadas por estudantes em hospital de emergência: estudo seccional

Bertine Mota Malta Brandão NUNES; Daniel Ferreira WANDERLEI; Maria Anilda dos Santos ARAÚJO; Glória Maria de FRANÇA

http://dx.doi.org/10.1590/1807-2577.20260008 Rev. odontol. UNESP, vol.55, e20260008, 2026
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Abstract

Introduction: The increasing antimicrobial resistance in hospital settings constitutes one of the threats to global public health. The improper use of Personal Protective Equipment (PPE), such as face masks, can facilitate cross-contamination and the spread of pathogens.

Objective: This study aimed to evaluate the microbiological contamination of masks used by health area students at the Alagoas Emergency Hospital, identifying the microorganisms present and analyzing their antimicrobial resistance profile.

Material and method: A cross-sectional and microbiological study with a descriptive and analytical approach was conducted. Masks used by medical and dental students during hospital internships were collected and subsequently subjected to microbiological culture according to the criteria of the Clinical and Laboratory Standards Institute (CSLI M100, 2025) and BrCAST.

Result: The presence of Staphylococcus aureus and Staphylococcus epidermidis was identified in the samples, indicating significant contamination. The antibiogram revealed resistance to erythromycin, oxacillin, and clindamycin in some isolated strains. Furthermore, the sample showed resistance to methicillin and that the bacterial load is inversely proportional to the efficacy of amikacin (p = 0.034; r = -0.327).

Conclusion: The masks used by students in hospital settings can act as vehicles for microbial contamination, and to reduce risks, students need prior training before entering the hospital environment.

Keywords

Microbiologia; máscaras; estudantes; farmacorresistência bacteriana; Staphylococcus aureus

Resumo

Introdução: A crescente resistência antimicrobiana em ambientes hospitalares constitui uma das ameaças à saúde pública global. O uso inadequado de Equipamentos de Proteção Individual (EPI), como máscaras faciais, pode facilitar a contaminação cruzada e a disseminação de patógenos.

Objetivo: Este estudo teve como objetivo avaliar a contaminação microbiológica de máscaras usadas por estudantes da área da saúde no Hospital de Emergência de Alagoas, identificando os microrganismos presentes e analisando seu perfil de resistência antimicrobiana.

Material e método: Foi realizado um estudo seccional e microbiológico com abordagem descritiva e analítica. Máscaras usadas por estudantes de medicina e odontologia durante estágios hospitalares foram coletadas e posteriormente submetidas à cultura microbiológica de acordo com os critérios do Clinical and Laboratory Standards Institute (CSLI M100, 2025) e BrCAST.

Resultado: A presença de Staphylococcus aureus e Staphylococcus epidermidis foi identificada nas amostras, indicando contaminação significativa. O antibiograma revelou resistência à eritromicina, oxacilina e clindamicina em algumas cepas isoladas. Além disso, a amostra demonstrou resistência à meticilina e que a carga bacteriana é inversamente proporcional a eficácia da amicacina (p = 0,034; r = -0,327).

Conclusão: As máscaras utilizadas por estudantes em ambientes hospitalares podem servir como veículos de contaminação microbiológica e, para reduzir agravos, os estudantes necessitam de treinamento prévio à entrada no ambiente hospitalar.

Palavras-chave

Microbiology; masks; students; drug resistance, bacterial; Staphylococcus aureus

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Submitted date:
03/09/2026

Accepted date:
07/30/2026

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