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Characterization of Inflammatory Responses During Intranasal Colonization with Streptococcus pneumoniae
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Nasopharyngeal bacterial interactions in children
Qingfu Xu1, Anthony Almudervar, Janet R Casey
1University Medical Center, Utrecht, the Netherlands.
Emerging Infectious Diseases
|October 25, 2012
Summary
Bacterial interactions in the nose change between health and acute otitis media (AOM). Streptococcus pneumoniae and Moraxella catarrhalis interact differently, impacting pathogen prevalence and potentially increasing Haemophilus influenzae in vaccinated children.
Area of Science:
- Microbiology
- Pediatrics
- Infectious Diseases
Background:
- Antimicrobial treatments and vaccines can significantly alter the complex bacterial interactions within the nasopharynx.
- Understanding these microbial dynamics is crucial for comprehending disease processes, particularly in respiratory infections.
Purpose of the Study:
- To investigate the colonization rates of three key respiratory bacterial pathogens in children.
- To analyze how bacterial interactions differ between healthy states and the onset of acute otitis media (AOM).
Main Methods:
- A cohort of 320 children was studied, examining colonization patterns of Streptococcus pneumoniae, Moraxella catarrhalis, and Haemophilus influenzae.
- Repeated measures logistic regression was employed to analyze the associations between bacterial colonization during health and AOM onset.
Main Results:
- In healthy children, S. pneumoniae and M. catarrhalis showed a synergistic association.
- S. pneumoniae colonization was competitively associated with Staphylococcus aureus in healthy children, but not during AOM.
- During AOM, H. influenzae exhibited competitive interactions with both S. pneumoniae and M. catarrhalis, with higher colonization rates observed for H. influenzae.
Conclusions:
- Bacterial interactions in the nasopharynx are dynamic, leading to altered pathogen prevalence during health versus AOM.
- The study suggests that H. influenzae may emerge as a more frequent cause of AOM in children who have received the pneumococcal conjugate vaccine.
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