Objective: To investigate the prevalence of Streptococcus pneumoniae in patients with respiratory tract infection and healthy children and to determine the antibiotic susceptibility in S. pneumoniae.
Methods: Sputum and throat swabs were collected from the adult and children patients. Nasopharyngeal specimens were collected from healthy children with aseptic swab and cultured for S. pneumoniae. Antibiotic susceptibility was determined by agar dilution method.
Results: The isolation rates of S. pneumoniae were 10% in both children and adult out-patients, being 30.2% in 2-6 year-old healthy children. Among 82 clinical isolates, only one was low-level resistant to penicillin (MIC 0.125 mg/L). In 228 S. pneumoniae strains from healthy children, 32 were low-level resistant to penicillin (MIC 0.125-0.5 mg/L), the resistant rate being 14.0%. S. pneumoniae was usually resistant to erythromycin, clindamycin and SMZ-TMP.
Conclusion: The penicillin-resistant strains are far more resistant to all the agents tested than susceptible strains except fluoroquinolones and vancomycin; in addition, several strains resistant to the third generation cephalosporins are found.