title: [Prevalence of Haemophilus influenzae carrier state in children in Ciudad Nezahualcóyotl, State of Mexico, Mexico].
abstract: OBJECTIVE
  To determine the prevalence of H. influenzae (Hi) carrier state among children, in Ciudad Nezahualcóyotl, State of Mexico.
  
  
  METHODS
  A cross-sectional comparative random study was designed. Study subjects were 639 children under 15 years of age, stratified by age and sex. Nasopharyngeal cultures were used to identify Hi and to typify encapsulated strains. Sample size was computed with the software package Epi-Info, using a p value of 0.5%, 95% confidence intervals and a 5% error; statistical analysis was performed using frequencies, means and proportions. Differences were tested by comparison of two proportions from independent populations.
  
  
  RESULTS
  Hi was isolated from 136 of 639 pharyngeal cultures (21%). Hi types found were Hi b (n = 6, 4%), Hi a, c, and f (n = 5, 4%), and non-typifiable (NT) Hi (n = 125, 92%).
  
  
  CONCLUSIONS
  The prevalence of pharyngeal colonization by Hi found among children under 15 years of age, in Ciudad Nezahualcóyotl, is similar to that reported in the literature. The inverse relation of pharyngeal carriers with age can be accounted for by the progressive development of specific and non-specific immunity against encapsulated and non-encapsulated strains.
authors.affiliation: Departamento de Infectología, Hospital Infantil de México Federico Gómez (HIMFG).
authors.forename: A
authors.initials: A
authors.lastname: Villaseñor-Sierra
authors.forename: E
authors.initials: E
authors.lastname: Herrera-Basto
authors.forename: P
authors.initials: P
authors.lastname: Vázquez-Salazar
authors.forename: J A
authors.initials: JA
authors.lastname: Arroyo-Moreno
authors.forename: J I
authors.initials: JI
authors.lastname: Santos-Preciado
mesh_terms: D000293:Adolescent; D000367:Age Factors; D002353:Carrier State / Q000453:epidemiology*; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D003627:Data Interpretation, Statistical; D005260:Female; D006192:Haemophilus Infections / Q000453:epidemiology*; D006193:Haemophilus influenzae / Q000302:isolation & purification; D006801:Humans; D007223:Infant; D008297:Male; D008800:Mexico / Q000453:epidemiology; D010614:Pharynx / Q000382:microbiology; D011897:Random Allocation; D018401:Sample Size; D012984:Software
vernacular_title: Prevalencia de estado de portador de Haemophilus influenzae en niños de Ciudad Nezahualcóyotl, estado de México, México.