Nasal carriage and antibiotic resistance of Staphylococcus aureus isolatesfrom hospital and non-hospital personnel in Abha, Saudi Arabia

The prevalence of nasal carriage of Staphylococcus aureus, antibiograms and prevalence of methicillin-resistant S. aureus (MRSA) were studied in 1999 among healthy hospital and non-hospital personnel in Abha, Saudi Arabia. S. aureus was isolated from 26(.)1% of 299 adults in the community and 25(.)4 % of 279 hospital personnel. No isolate was resistant to vancomycin. Antibi otic resistance rates, for all other antibiotics tested except cephalothin, were significantly higher for strains from hospital personnel (P values < 0(.)001-0(.)04) compared to non-hospital adults. The antibiograms were also compared with those of 140 clinical isolates. The rates of resistance of t he inpatient strains to all the antibiotics tested were significantly highe r than those of hospital nasal carrier strains (P < 0(.)001-0(.)05). MRSA w as isolated, respectively, from 5(.)1% and 18(.)3% of non-hospital and hosp ital carriers; MRSA carriage rates were 1(.)3% and 4(.)7%, respectively, fo r non-hospital and hospital carriers, and 6(.)1% of S. aureus isolates from infected patients were MRSA. Only 8% of non-hospital but 44% of hospital c arrier strains were multiply resistant (P < 0(.)001). Multiple resistance a mong inpatient strains (89%) was significantly higher than that among hospi tal nasal strains (44%) (P < 0(.)001). Such rates of multiple resistance an d endemic MRSA prevalence among healthy carriers (11%) at a much higher rat e than those reported in the literature should raise concern in a region wi th unrestricted availability of antibiotics.