Emergence of Streptococcus pneumoniae of serotype 19A in France: molecular capsular serotyping, antimicrobial susceptibilities, and epidemiology

We have studied 457 Streptococcus pneumoniae isolated in 2007 from adults and children. For all isolates, both latex agglutination and molecular capsular typing were performed. Antibiotic resistance patterns were determined. S. pneumoniae 19A was the most frequently isolated serotype (34.7%) both in children and adults. It represented 12.8% of the strains isolated from invasive infections in adults and 27.0% in children and 63.6% (110/173) of strains isolated from acute otitis media. Between children and adults, no difference concerning antibiotic susceptibility was observed for penicillin, amoxicillin, cefotaxime, and erythromycin in strains isolated from invasive diseases. Comparing antibiotic susceptibilities according to the serotype, the 19A isolates appeared to be the least susceptible to penicillin (3.2%) and erythromycin (4.5%), followed by serotypes 19F and 14. We confirm the predominance of serotype 19A among S. pneumoniae responsible for invasive and noninvasive diseases either in children or adults in France.