Results: A total of 4,001 nasal swabs were collected, and 3,969 were tested for identification, 765 S. aureus were tested for resistance. Resistance rates to penicillin, azithromycin and methicillin were 87.1%, 11.6% and 1.3%, respectively, and a total of 10 MRSA strains were isolated (1.3%). Penicillin-resistant staphylococci were statistically significantly associated with the previous number of packages of penicillin dispensed (OR, 1.18; 95% CI, 1.04–1.35).