Evaluation of methicillin-resistant Staphylococcus aureus nasal carriage in Malagasy patients

Introduction: Methicillin-resistant Staphylococcus aureus (MRSA) is an important cause of infections. It is well recognized that nasal carriage of S. aureus represents a potent and increasingly prevalent risk factor for subsequent S. aureus infection. However, in Madagascar no data exist concerning this nasal carriage of S. aureus . Methodology: Nasal swabs from 304 different patients attending the Laboratory of Training and Research in Medical Biology of Madagascar were cultured for methicillin sensitive (MSSA) and MRSA. Results: One hundred and sixteen patients had S. aureus in their noses (38.16 ± 5.46%) of whom 45 (14.80 ± 3.99%) had MRSA.  A risk factor for MSSA nasal carriage included a history of hospitalization when antibiotics were administered (odds ratio [OR] 2.25, 1.09 - 4.64). Among MRSA nasal isolates, high rate of resistance to other antibiotics was observed, particularly for trimethoprim-sulfamethoxazole (68.89%), erythromycin (66.67%) and ofloxacin (53.33%). Conclusion: Our data showed a high rate of MRSA nasal carriage and a high rate of multidrug resistance. A strategic policy against the spread of multidrug resistant strains is desirable.