Streptococcus pneumoniae colonisation in children and adolescents with asthma: Impact of the heptavalent pneumococcal conjugate vaccine and evaluation of potential effect of thirteen-valent pneumococcal conjugate vaccine

Background The main aim of this study was to evaluate Streptococcus pneumoniae carriage in a group of school-aged children and adolescents with asthma because these results might indicate the theoretical risk of invasive pneumococcal disease (IPD) of such patients and the potential protective efficacy of the 13-valent pneumococcal conjugate vaccine (PCV13). Methods Oropharyngeal samples were obtained from 423 children with documented asthma (300 males, 70.9 %), and tested for the autolysin-A-encoding (lytA) and the wzg (cpsA) gene of S. pneumoniae by means of real-time polymerase chain reaction. Results S. pneumoniae was identified in the swabs of 192 subjects (45.4 %): 48.4 % of whom were aged