Author(s)

Catalina Ulloa, Alfonso Pereira, Carolina Soley, Nurith Porat, Arturo Abdelnour, Ron Dagan, Adriano Arguedas

Instituto de Atención Pediátrica, San José, Costa Rica.
Instituto de Atención Pediátrica, San José, Costa Rica; Universidad de Ciencias Médicas, San José, Costa Rica.
Pediatric Infectious Disease Unit, Soroka University Medical Center and the Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.

Objective: The aim of this study was to analyze the NP/OP S. pneumoniae serotype distribution and potential vaccine coverage in Costa Rican children with Otitis Media (OM) before the introduction of PCV-7 in the National Immunization Program (NIP). Methods: Between 2002 and 2006, NP and OP samples were obtained from 641 children from 6 to 79 months of age, at the time of OM diagnosis. S. pneumoniae serotyping and antimicrobial susceptibility were performed. Results: 386 S. pneumoniae isolates were recovered. The most common S. pneumoniae serotypes (ST) were: ST 6B, ST 14, ST 19F. Penicillin non-susceptibility was observed among 57% of the isolates obtained from children < 24 months of age. 15% strains were multidrug resistant. Potential vaccine coverage was: PCV-7: 60%; PCV-10: 62%; and PCV-13: 76% and against penicillin non-susceptible and multidrug resistant isolates was: PCV-7; 59% and 83%, respectively; PCV-10: 60% and 85%, respectively and PCV-13: 74% and 96%, respectively. Conclusions: S. pneumoniae was isolated from the NP and/or OP in the majority (59%) of studied children with OM. At a statistical significant level, only serotype 3 was more frequently isolated among children >24 months of age. Antibiotic non-susceptibility and MDR were significantly higher in children <24 months of age. This study demonstrates that PCV-13 offers the highest potential vaccine coverage and serves to assess the impact of introduction of one of the conjugated vaccines in the NIP in Costa Rica.

Streptococcus pneumoniae; Serotypes; Nasopharynx; Oropharynx; Pneumococcal Conjugated Vaccine

C. Ulloa, A. Pereira, C. Soley, N. Porat, A. Abdelnour, R. Dagan and A. Arguedas, "Streptococcus pneumoniae Upper Respiratory Carriage in Costa Rican Children with Otitis Media before the Introduction of the Heptavalent Conjugated Vaccine in the National Immunization Program," World Journal of Vaccines, Vol. 3 No. 2, 2013, pp. 39-45. doi: 10.4236/wjv.2013.32007.