Clonal and clinical profile of Streptococcus pneumoniae serotype 19A causing pediatric invasive infections: A 2-year (2007-2009) laboratory-based surveillance in Madrid

Studies of clonality and clinical profile of serotype 19A invasive pneumococcal disease in children (IPD-19A) are worthy after PCV7 introduction. A prospective, hospital-based surveillance of IPD-19A, culture and/or PCR confirmed, was performed in 2007-2009 in Madrid (all 22 hospitals with pediatric departments). Sixty-two cases were found: 90.3% in children <5 years, 87.1% in <36 months, and 74.2% in ≤18 months. Clinical presentations: meningitis (22.6%), primary bacteremia (19.4%), secondary bacteremia to otic foci (SBOF; 17.7%), bacteremic pneumonia (17.7%), pediatric parapneumonic empyema (PPE; 17.7%) and others (4.8%). Presentations by age: meningitis (35.7%), SBOF (28.6%) and primary bacteremia (21.4%) in children <12 months, bacteremic pneumonia, PPE and primary bacteremia (26.3% each) in 12-23 months, and bacteremic pneumonia (33.3%) and PPE (26.6%) in ≥24 months. Sequence types ST276 and ST320 represented 83.0% isolates, all oral-penicillin/erythromycin non-susceptible. In nonmeningeal isolates, non-susceptibility to parenteral penicillin/cefotaxime was 0%/17.6% (ST276) and 93.8%/75.0% (ST320). Non-susceptibility in ST276 and ST320, prevalence of these STs among 19A isolates, and serotype 19A prevalence among IPDs, indicate the importance of 19A inclusion in PCV13 for IPD-19A prevention and for reducing 19A nasopharyngeal carriage, thus preventing 19A otitis (one-third of 19A bacteremia in this study were from otic origin).