Methicillin resistant Staphylococcus aureus (MRSA): an interim report of carriage and conversion rates in nursing students.

Objective: To evaluate and characterize MRSA and staphylococci carriage and conversion rates in nursing students across clinical semester rotations and to describe risk factors.

Design: A prospective, longitudinal cohort design (interim report) with three times of measurement. Data collected between August 2010 and May 2011 (ongoing longitudinal study to May 2012). Institutional Review Board approval (2010F5693).

Setting: Texas State University, San Marcos, TX.

Participants: Eighty-seven nursing students.

Interventions: A positive MRSA swab represented an end-point for a participant. Intervention offered was bactroban (mupirocin) for nasal decolonization and an oral antibiotic, doxycycline; posttreatment collection to verify decolonization prior to next clinical rotation.

Main outcome measures: Screening for Staphylococcus aureus and MRSA identification; confirmation and antibiotic susceptibility by Vitek 2. Self-administered questionnaires collected demographics and risk factors. Generalized estimating equations calculated population-averaged panel logistic regression models allowing for an AR(1) error by Stata version 12.

Results: MRSA colonization did not increase. S. aureus prevalence (20-26%). Species prevalence other than S. aureus increased (9.2% to 80%). The following associations were found to be statistically significant: boil or skin infection odds with S. aureus (OR = 2.43, p < .05), working or volunteering in healthcare facility odds with S. other (OR = 2.72, p < .05) and gym and sports activities odds with S. other (OR = 4.98, p < .001).

Conclusions: MRSA colonization did not increase. Knowledge and understanding of MRSA (risks) may play a role in compliance and barrier precautions. S. aureus colonization remained stable (25-30%). Species colonization other than S. aureus (e.g. S. epidermis, S. haemolyticus) increased to significant levels.