Nasal carriage of multi-drug resistant Staphylococcus aureus in healthy inhabitants of Amassoma in Niger delta region of Nigeria.

Background: Nasal Staphylococcus aureus is a major source of community and hospital associated staphylococcal infections. This study determined the prevalence of nasal S. aureus isolates and investigated their antimicrobial resistance profile in healthy volunteers.

Methods: Nasal specimens of healthy volunteers in Amassoma were cultured and screened for S. aureus using standard microbiological protocols and their antibiotic profile susceptibility was investigated using disc diffusion and agar dilution techniques.

Results: A total of 40 (33.3%) S. aureus isolates were obtained from 120 nares specimens screened. Twenty three (57.5%) and 17 (42.5%) of the isolates were from university students and villagers respectively. The isolates showed an overall 75% resistance to ampicillin, 52.5% to doxycycline, 47.5% to chloramphenicol, 35% to erythromycin and 32.5% to cotrimoxazole; with 27.5% methicillin resistant. No isolate was resistant to gentamicin while few isolates were resistant to cefuroxime (2.5%), augmentin (5.0%), ciprofloxacin (10.0%), ofloxacin (10.0%) and vancomycin (7.5%). Twenty one (52.5%) of all the isolates were multi-drug resistant, ten (47.6%) of which were methicillin resistant Staphylococcus aureus (MRSA) and only 3 (7.5%) were fully susceptible to all the tested antimicrobial drugs.

Conclusions: The observation calls for strategies to prevent their spread to more vulnerable populations where the consequences of their infections can be severe.