Nasal carriage of antibiotic-resistant staphylococci among undergraduate medical students, with special reference to methicillin-resistant Staphylococcus aureus

Abstract

Background: Staphylococcus aureus and other staphylococci are the commensals of the human body, the anterior nares being an important niche for colonisation. The medical students constitute an important component of the hospital population. Studies of staphylococcal carriage among the medical students are almost non-existent from India. This study was conducted with the primary aim of finding out the nasal carriage of antibiotic-resistant staphylococci among the medical students in our institution. Methods: A total of 162 medical students equally divided between the preclinical and clinical batches were the study participants. A nasal swab was collected from the participants and cultured. Suspected colonies were identified as S. aureus and antimicrobial susceptibility done by standard methods. The students were also asked to fill up a questionnaire to identify any risk factor associated with staphylococcal carriage. Results: The overall colonisation rate was 48.8% for S. aureus with 45.7% in the non-exposed pre-clinical students' group to 51.8% in the exposed clinical students' group which was not significant. The carriage rate for methicillin-resistant S. aureus was 6.3% among the S. aureus isolates. A survey of the risk factors revealed no significant association of hostel stay, family size, previous hospital admission, skin or soft-tissue infection with increased carriage rate. However, a history of previous antibiotic therapy had a significant association with nasal carriage. Conclusions: High rates of colonisation with S. aureus calls for further detailed multicentric studies with application of moecular methods from India.

Keywords

• carriers
• medical
• methicillin-resistant staphylococcus aureus
• staphylococcus
• students