Susceptibility patterns of Staphylococcus in a family practice population.

Nasal swabs were obtained from 408 patients seen in a family practice office in an attempt to identify Staphylococcus aureus carriers. Isolated strains were tested for sensitivity to 11 antibiotics. Study participants were interviewed to obtain the following data: age, history of recent hospitalization and/or recent antibiotic use, number of household members, and occupation, if employed in a health-care facility. S aureus was isolated from 109 nasal swabs. This represents a 26.7 percent carrier rate. Only 25.7 percent of the isolates were sensitive to penicillin G and ampicillin. No statistically significant association was found between the patient variables and either the carrier rate or the sensitivity of the S aureus isolates to penicillin. The sensitivity testing demonstrated that 94.5 percent of the isolates were sensitive to tetracycline and erythromycin. Ninety-nine to 100 percent of the isolates were sensitive to all other antibiotics tested. The authors conclude that penicillin G should not be used in the treatment of S aureus infections. Erythromycin, due to demonstrated sensitivity and reasonable cost, is recommended for mild to moderate infections.