Background: Nasopharyngeal colonization plays an important role for infections caused by Streptococcus pneumoniae. Emergence of penicillin resistance in this organism has made it difficult to treat pneumococcal infections. The objectives of this study were to investigate the risk factors for nasopharyngeal colonization with S. pneumonia and for nasopharyngeal colonization with penicillin-resistant S. pneumoniae.
Methods: Three hundred children with or without evidence of infection were investigated for various risk factors. Streptococcus pneumoniae isolated from children's nasopharyngeal swabs were examined for penicillin susceptibility.
Results: Day-care attendance (odds ratio OR=2.82, P=0.003) and upper respiratory tract infection within the last month (OR=1.83, P=0.02), have been determined to be risk factors for S. pneumoniae carriage. The use of antibiotics within the last 3 months (OR=81.07, P<0.001), the presence of more than five people living in the house of the child (OR=6.63, P=0.03), and having a sibling under 5-years-old (OR=4.60, P=0.03) have been determined to be risk factors for penicillin-resistant S. pneumoniae carriage.
Conclusion: Some children are inevitably exposed to and colonized with penicillin susceptible or resistant S. pneumoniae. Changes in day-care organizations, better living conditions, and restriction of antibiotic use seems to be useful precautions to prevent the emerging and colonization with penicillin-susceptible or -resistant S. pneumoniae.