C2-249. Prevalence and Risk Factors for Nasopharyngeal Carriage of Streptococcus pneumoniae Among Children in Daycare Centers in Argentina
Session: Poster Session: Resistance in Streptococcus pneumoniae
Saturday, October 25, 2008: 12:00 AM
Room: Hall C
Background: Streptococcus pneumoniae (Spn) nasopharyngeal carriage (NPC) plays an important role in pneumococcal infections. Objectives: to assess the rate and risk factors of Spn NPC in children attending daycare centers (DCC), to determine serotype distribution and oxacillin resistance (OXA-R) of Spn isolates. Methods: a prospective multicenter study was conducted in 7 centers throughout Argentina, in winter season, in healthy children below 3 years of age, who had not been vaccinated with pneumococcal vaccine. For each positive sample two colonies with pneumococcal characteristics were isolated; identification of Spn, serotyping and OXA-R was performed using routine laboratory methods. Results: 381 children were enrolled: Buenos Aires city 18.4%, Corrientes 15.7%, Rosario 14.7%, Catamarca 14.4%, Trelew 13.4%, Salta 13.1%, and Buenos Aires surrounding area 10.2%. Overall NPC rate was 55.4% [211/381, 95% confidence interval (CI) 50.3-60.5] with range of 40% in Catamarca, Corrientes and Salta to 80.4% in Rosario. In a multivariate analysis independent predictors for Spn NPC was the age ≥ 7 months. 418 Spn isolates (211 samples) were serotyped, the most frequent were: 6B:10.1%, 19F: 9.3%, 15B:9.1%, 14:8.9%, 6A:8.4%, 23F:8.1%, 15C:5.5%, 19A:4.3% and 9V:4.1% Spn serotypes distribution were variable except Catamarca, the 50% of Spn isolates (22/44) carried 15B.
The 11.4% (24/211) of the positive carriers showed two different serotypes, being Catamarca the most significative situation, 37.5% [9/24, OR 8.03 (CI) 2.65-24.45, p=0.00002] had different serotypes.
OXA-R was 44.7% (187/418). Serotypes associated with >50% resistance were: 23B, 19A, 6B, 6A, 14, 9V. Conclusions: 1-Spn NPC was >50% in children <3 years of age 2- NPC increased with age, 3- Great variations in Spn NPC rates were observed within regions.4-almost 45% of isolates showed OXA-R.
S. Pneumoniae WORKING GROUP, Angela Gentile, Cecilia Sorhouet Pereira, BIOCHEMIST2, Mabel Regueira, biochemistry3, PATRICIA Lamy, MC4, Sofia Fossati, Bioquemistry3 and  A. Gentile, None., (1)INEI- ANLIS C. MALBRAN, (2)ANLIS Malbran, (3)Ricardo Gutierrez Children Hospital