[Nasopharyngeal carriage of Streptococcus pneumoniae in healthy children, 2 to 24 months of age, in New-Caledonia]. / Etude du portage rhinopharyngé de Streptococcus pneumoniae chez les enfants sains âgés de 2 à 24 mois en Nouvelle-Calédonie.

OBJECTIVES: The aims of this study were to determine the prevalence of pneumococcal nasopharyngeal carriage in New-Caledonian children less than two years of age, to define risk factors for carriage, and to document the serotypes present in New Caledonia prior to the implementation of the conjugate pneumococcal vaccine. METHOD AND RESULTS: From August 2002 to April 2003, nasopharyngeal samples were collected on 1040 children less than two years of age during scheduled visits to dispensaries for routine immunization. Of the 1040 samples, 544 (52%) were positive for Streptococcus pneumoniae. The percentage of pneumococcal strains with reduced susceptibility to penicillin (PRSP) was 21%. Several risk factors for pneumococcal carriage were identified. These included the Province that the child lived in, the ethnic group, age, and having a sibling less than 6 years of age. Risk factors for carriage of PRSP carriage were similar but also included additional risk factors such as attendance at day care and a history of antibiotic treatment. The eight most frequent serotypes were 6B, 19F, 14, 23F, 6A, 19A, 11A, and 16F. These serotypes accounted for 60% of all strains detected. The most frequent serotypes of PRSP were 14, 9 V, 19F, 23F, and 6B. They were more often identified in european children and 80% were vaccine serotypes. However, overall 250/544 (46%) of all pneumococcal isolates were those included in the 7 serotype vaccine.