Background:

Nosocomial infections caused by strains of methicillin-resistant Staphylococcus aureus (MRSA) are a major health problem throughout the world. This microorganism produces a wide variety of infections including osteomyelitis, invasive endocarditis, septic arthritis, and septicemia. S. aureus is usually found in the skin and nasal cavity, it is easily spread through fomites, skin-skin contact or contact with nasal fluids. The students of the EMM are in continuous contact with patients of the Hospital Central Militar and can acquire or disseminate this type of microorganisms. Hence the importance of preventive medicine, in order to assess the frequency of this microorganism and use sanitary measures that can prevent its spread.

Objective:

To determine the frequency of resistant methicillin-resistant Staphylococcus aureus (MRSA) carriers in students of the Escuela Militar de Medicina.

Methodology:

Mucosa samples from the nasal cavity of students of the Escuela Militar de Medicina from the 2nd to 5th year, were cultured on blood agar and salt-mannitol agar, strains with corresponding colonial and microscopic morphology were selected S. aureus, tests were performed of catalase and coagulase, positive strains of S. aureus were subjected to antibiogram using oxacillin sensitives and the resistance was determined from the diameter in the inhibition zone. Student carriers received eradicating treatment with intranasal 5% mupirocin for 7 days and samples were taken again to determine the persistence of S. aureus in the nasal cavity.

Results:

Of the 110 students of the Escuela Militar de Medicina who were sampled 51 patients (46.36%) were positive carriers to S. aureus, the antibiogram with oxacillin discs showed a resistance to methicillin of 12 patients corresponding to 10.9%, while that with antibiotic eradication therapy with 5% intranasal mupirocin, the presence of resistant S. aureus Methicillin decreased to 0%.

Conclusions:

A 10.9% of students carriers of resistant S. aureus methicillin were obtained, which was eradicated in its entirety with 5% intranasal mupirocin.