Nasal carriage of methicillin and inducible clindamycin resistant Staphylococcus aureus among healthcare workers in a tertiary care hospital, Kathmandu, Nepal

Abstract

Introduction and Objectives: Transmission of methicillin-resistant Staphylococcus aureus (MRSA) from healthcare workers is one of the most frequent causes of nosocomial infections globally. There is a significant burden of nosocomial MRSA infections in low and low-middle income countries (LMICs), including Nepal. The present study investigated the rate of nasal carriage of MRSA among the healthcare workers in a tertiary care hospital, in Kathmandu, Nepal with emphasis on inducible macrolide-lincosamide-streptogramin B (iMLSB) resistance. Material and method: The study was conducted at Star Hospital, Lalitpur, Nepal, from September 2022 to November 2022. Healthcare workers (HCWs) working at the diffeerent departments of the hospital were enrolled. Nasal swabs from both anterior nares of HCWs were collected aseptically and cultured on Mannitol Salt agar. S. aureus was identified by Gram stain and standard biochemical tests. Antibiotic susceptibility of S. aureus was performed by disc diffusion method. MRSA isolates were detected phenotypically by disc diffusion method using cefoxitin disc (30 µg), and inducible clindamycin resistance was detected phenotypically by the D-zone test. Results: Total 105 HCWs were enrolled in the study. Out of 105 HCWs, 14 (13.3%) were positive for S. aureus among which 6 (5.7%) were MRSA carriers. The nasal carriage of MRSA was highest among doctors (16.7%) and the HCWs of the post-operative department (14.3%). All the isolated MRSA were susceptible to chloramphenicol and vancomycin. Inducible MLSB resistance was detected in 33.3% MRSA while the rate was 21.4% in all isolated S. aureus. Conclusion: The study demonstrated that HCWs could be the potential source of nosocomial infection by methicillin and inducible clindamycin resistant S. aureus. Thus, preventive measures should be initiated to mitigate the risk of its spread and the test for detection of inducible clindamycin resistance should be incorporated into the routine antibiotic susceptibility testing in hospital settings. IMC J Med Sci. 2024; 18(1):005. DOI: https://doi.org/10.55010/imcjms.18.005 *Correspondence: Gaurab Pandey, Non-Communicable Disease Laboratory, National Public Health Laboratory, Teku, Kathmandu, 44600, Nepal; E-mail: pandeygaurab67@gmail.com