Résumé
PURPOSE: The aim of this study was to determine the prevalence of pneumococcal nasal carriage and confirm the distribution of pneumococcal capsular serotypes in Korean children below aged 5 years old. Another reason this study was performed was to identify the theoretical coverage by seven valent conjugate pneumococcal vaccine, and confirm the penicillin resistant rate. METHODS: This study included 213 children, who visited out patient clinic or were hospitalized in six hospitals between August 2001 and April 2002. Nasopharyngeal swabs and cultures for S. pneumoniae were performed. Serotyping of isolated samples was performed by the Quellung reaction at the Statens Seruminstitut in Copenhagen. Penicillin MICs were determined by the agar dilution method, and interpreted according to the NCCLS guide line. RESULTS: The prevalence of pneumococcal nasal carriage rate in this study was 34.3%. A total of 31 of 73 isolates(42.5%) had intermediate resistance to penicillin, and 29 of 73 isolates(39.7%) showed a high resistance to penicillin. The predominant serotype of the S. pneumoniae isolates was 23F(22%), and the percentages of vaccine serotypes(46.6%) and associated serotypes(37%) which belong to the seven-valent pneumococcal conjugate vaccine were 83.6%. The resistance pattern of pneumococcal isolates to penicillin was different among the serotypes. CONCLUSION: Pneumococcal isolates from nasal colonization of Korean children showed a high penicillin resistant rate. We assumed that newly developed seven-valent pneumococcal conjugate vaccine may offer a high theoretical coverage for the isolated strains.