Higher nasal carriage rate of methicillin-resistant Staphylococcus aureus among dental students who have clinical experience

• Published in: The Journal of the American Dental Association (1939) Vol. 147; no. 5; pp. 348 - 353
• Main Authors: Baek, Yoo Sang, MD, Baek, Seung-Ho, DDS, PhD, Yoo, Yeon-Jee, DDS, PhD
• Format: Journal Article
• Language: English
• Published: England Elsevier Inc 01.05.2016; American Dental Association
• Subjects: College students; colonization; Dental care; Dental health; Dental research; dental student; Dentistry; Methicillin-resistant Staphylococcus aureus; MRSA; nasal carriage; Staphylococcus aureus; Staphylococcus infections; Personal protective equipment; Health care professional; CDC; Not applicable; PPE; TMP-SMX; nasal carriage; CA-MRSA; Trimethoprim and sulfamethoxazole; HA-MRSA; R; S; Centers for Disease Control and Prevention; colonization; MRSA; SCC mec; Staphylococcal cassette chromosome mec; Hospital-associated methicillin-resistant Staphylococcus aureus; dental student; Community-associated methicillin-resistant Staphylococcus aureus; DHCP; Polymerase chain reaction; NA; HCP; Dental health care professional; Methicillin-resistant Staphylococcus aureus; Susceptible; Resistant; PCR; SCCmec
• ISSN: 0002-8177; 1943-4723
• DOI: 10.1016/j.adaj.2015.12.004

Abstract Background Methicillin-resistant Staphylococcus aureus (MRSA) has been isolated from dental clinical surfaces, dental patients, and dental health care professionals. The authors conducted a study to determine the prevalence rate of nasal MRSA colonization among dental school students and to identify the characteristics of the isolated strains. Methods The authors collected nasal samples from 159 dental students. The authors performed mec A gene detection, staphylococcal cassette chromosome mec (SCC mec ) typing, and antimicrobial susceptibility tests on each sample. The authors compared the results of 2 groups (students who had clinical experience and students who did not have clinical experience). Results Five (3.1%) dental students had MRSA colonization, as confirmed by the presence of the mec A gene in the nasal cavity. Prior clinical experience was associated significantly with nasal MRSA carriage ( P  < .05). Four of the strains were SCC mec type IV, and 1 strain was SCC mec type I. All isolates were resistant to amoxicillin and clavulanic acid, imipenem, and oxacillin, but were susceptible to several antimicrobial agents including mupirocin, trimethoprim and sulfamethoxazole, and rifampin. The nasal MRSA colonization was eradicated with the use of mupirocin ointment. Conclusions Nasal MRSA colonization occurs in some dental students, especially those who have clinical experience. Practical Implications Education about MRSA colonization and transmission, as well as infection prevention and control measures is necessary for dental students, especially when they participate in clinical practice.