Nasal Carriage of Methicillin-Resistant Staphylococcus aureus in Intensive Care Units of Two University Hospitals in Cameroon

Aim: The aim of this work was to carry out a screen for methicillin-resistant Staphylococcus aureus (S. aureus) in nasal cavity of patients in the intensive care units of the University Hospital Center (UHC) and the Central Hospital of Yaounde (CHY) in Cameroon.

Study Design: A cross-sectional descriptive study was carried out.

Pace and Duration of the Study: Collection of nasal swab was done in Intensive Care Unit of University Teaching Hospital of Yaounde, and Intensive Care Unit of Central Hospital of Yaounde. Identification and susceptibility test were done in bacteriology laboratory of University Hospital Center, Yaounde between August 2018 and March 2019.

Methods: Nasal swabs were collected from patients by performing rotation in each nose. The identification of bacteria was carried out by observation of mannitol fermentation on Chapman agar, catalase, coagulase and DNAse tests. The susceptibility test was carried out by the method of diffusion of the discs in Mueller-Hinton agar.

Results: A total of 29 S. aureus were identified from 127 patients of which 44.10% were women and 55.90% were men. The antibiotic resistance profile showed cross-resistance of S. aureus between cefoxitin and others antibiotics with high resistance of amoxicillin, Amoxi / Clavulanic, fusidic acid, gentamycin and tetracycline with rates ranging from 62% to 82%. We detected 58.62% resistant species to cefoxitin and 51.72% were resistant to vancomycin. Statistical analysis found that there was not association between age groups, gender with nasal carriage of S. aureus. However there was an association (P=0,0060) between the hospital attended and the portage of S. aureus.

Conclusion: The prevalence of Methicillin-resistant S. aureus (MRSA) is quite high in intensive care patients. Staphylococcus aureus isolated from carriers also shows resistance to others antibiotics. This can increase the incidence of nosocomial infections. There is a need to implement effective control strategies to prevent infection cross transmission in intensive care Units.