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[Haemophilus influenzae nasopharyngeal colonization in children]

Fortino Solórzano-Santos1, Ma Guadalupe Miranda-Novales, Blanca Leaños-Miranda

  • 1Departamento de Infectología, Hospital de Pediatría, Centro Médico Nacional Siglo XXI, Instituto Mexicano del Seguro Social, Distrito Federal, México. fortino.solorzano@imss.gob.mx

Revista Medica Del Instituto Mexicano Del Seguro Social
|December 22, 2011
PubMed

Insights

Nontypable Haemophilus influenzae is common in Mexico City children under five. Invasive Haemophilus influenzae type b (Hib) colonization is low, primarily affecting unvaccinated or partially vaccinated children.

Area of Science:

  • Microbiology
  • Pediatrics
  • Infectious Diseases

Background:

  • Haemophilus influenzae is a significant cause of bacterial infections in children worldwide.
  • Understanding serotype distribution and antimicrobial susceptibility is crucial for disease prevention and treatment strategies.
  • Vaccination, particularly against Haemophilus influenzae type b (Hib), has dramatically reduced invasive disease incidence.

Purpose of the Study:

  • To investigate the prevalence, serotypes, biotypes, and antibiotic susceptibility of Haemophilus influenzae nasopharyngeal isolates in young children in Mexico City.
  • To assess the carriage rate of Haemophilus influenzae type b (Hib) and its association with vaccination status.

Main Methods:

  • A cross-sectional survey was conducted involving children aged two months to five years.
  • Nasopharyngeal samples were collected for Haemophilus influenzae identification.
  • Isolates underwent serotyping, biotyping, and antimicrobial susceptibility testing against eight antibiotics.

Main Results:

  • Haemophilus influenzae was isolated from 15.3% of 573 children.
  • Nontypable H. influenzae (NTHi) was the predominant type (13.6%), followed by Hib (1.2%).
  • Biotype VIII was the most common (76.1%), and most isolates were susceptible to antibiotics, with one Hib strain showing erythromycin resistance.

Conclusions:

  • Nontypable H. influenzae is the predominant serotype colonizing the nasopharynx in this pediatric population.
  • Hib colonization is low (1.2%) and associated with incomplete vaccination schedules in children under five.
  • Findings highlight the importance of continued surveillance and vaccination programs.
Abstract

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