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Characterization of Inflammatory Responses During Intranasal Colonization with Streptococcus pneumoniae
09:12

Characterization of Inflammatory Responses During Intranasal Colonization with Streptococcus pneumoniae

Published on: January 17, 2014

Nasopharyngeal colonization of infants in southern India with Streptococcus pneumoniae

R Jebaraj1, T Cherian, P Raghupathy

  • 1Department of Child Health, Christian Medical College and Hospital, Vellore, India.

Epidemiology and Infection
|February 29, 2000
PubMed

Insights

Most infants experience Streptococcus pneumoniae colonization, with common serogroups like 6 and 19. Antimicrobial resistance was low, but invasive isolates showed higher resistance to cotrimoxazole.

Area of Science:

  • Microbiology
  • Pediatrics
  • Epidemiology

Background:

  • Nasopharyngeal colonization by Streptococcus pneumoniae is common in infants.
  • Understanding the dynamics of colonization, prevalent serogroups/types (SGT), and antimicrobial susceptibility is crucial for public health.

Purpose of the Study:

  • To investigate the dynamics of nasopharyngeal colonization with Streptococcus pneumoniae in infants.
  • To determine the prevalent SGTs and their antimicrobial susceptibility.
  • To compare susceptibility patterns between colonizing and invasive isolates.

Main Methods:

  • Prospective study of 100 infants from a well-baby clinic.
  • Nasopharyngeal swabs collected at multiple time points (6 weeks to 18 months).
  • Culture, serotyping, and antimicrobial susceptibility testing of Streptococcus pneumoniae isolates.

Main Results:

  • 81% of infants were colonized at least once, with median acquisition at 11 weeks and carriage duration of 1-3 months.
  • Common SGTs identified were 6, 19, 14, and 15; SGT 1 was notably absent.
  • Low resistance rates observed for penicillin (0%), chloramphenicol (6%), cotrimoxazole (5%), and erythromycin (3%).
  • Invasive isolates showed significantly higher resistance to cotrimoxazole compared to colonizing isolates (40% vs. 5%, P<0.0001).

Conclusions:

  • Infant nasopharyngeal colonization with Streptococcus pneumoniae is highly prevalent.
  • Specific SGTs dominate colonization, with notable absence of SGT 1.
  • Low antimicrobial resistance in colonizing strains, but higher resistance in invasive strains warrants further investigation.

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