The Authors carried out a study on MRSA colonization rate among health-care workers (HCW) in a large roman hospital. Samples were obtained from staff members at the beginning of each work shift. Two-hundred HCW were included (78 physicians and 122 nurses), mean age 36.6 +/- 10.9 years. We identified 38 (19.0%) S. aureus carriers, prevalently nurses (21.3%) vs. physicians (15.4%). Results showed a RR 2,7; IC95% 1.47-4.86; p < 0.01 among men vs. women. Overall three (1.5%) MRSA strains were isolated among HCW (two nurses and one physician). None of them was a CA-MRSA. The study suggests that HCW act principally as cross transmission vectors and not as main sources of MRSA.