Streptococcus pneumoniae carriage rate in healthy preadolescent dental patients

Abstract

Introduction. Streptococcus pneumoniae is the major cause of death for pneumonia in the world, responsible 800,000 deaths annually among children and elderly. Most pneumonia caused by pneumococci are healthcare associated, while the remaining are community acquired. Airborne infections are frequent in dental healthcare settings, but data regarding the risk for pneumococci transmission are lacking. Aim. To estimate S. pneumoniae carriage rate among adolescent dental patients, in order to investigate the risk for pneumococci acquisition and spread in dental healthcare settings. Material and methods. 199 children aged 10-12 years attending the paediatric dentistry section of a dental hospital in Rome underwent oropharyngeal swab samples. Pneumococci were presumptively identified with cultural methods (growth on selective media, alpha haemolysis, bile solubility). Routine exposure to passive smoking, use of antibiotics, recent respiratory tract infections (RTIs) were anamnaestically investigated. Unadjusted and adjusted odds ratios (ORs) and individual probability to carry S. pneumoniae were assessed with logistic regression analysis. Results. Overall S. pneumoniae carriage rate was 11.6% (95% confidence interval, 95CI, 7.2-16.0%). RTIs were significantly associated with carriage (adjusted OR, 3.3; 95CI, 1.3-8.7), exposure to passive smoking (OR, 2.0; 95CI, 0.8-4.9), male gender (OR, 3.2; 95CI, 0.6-17.1) were marginally associated (0.05<p<0.20). According to the regression model, male patients with recent RTI history and routinely exposed to passive smoking yielded 58.2% probability to carry pneumococci. Conclusion. S. pneumoniae carriage rate in healthy preadolescent dental patients was moderately high. Patient's profile could be helpful to identify potential carriers and to adopt transmission-based precautions.