Epidemiology of nasopharyngeal colonization with nontypeable Haemophilus influenzae in the first 2 years of life

J Infect Dis. 1995 Jul;172(1):132-5. doi: 10.1093/infdis/172.1.132.


Two hundred children were followed from birth through 2 years of age with nasopharyngeal cultures to determine the normal colonization pattern of nontypeable Haemophilus influenzae. Forty-four percent of the children were colonized on one or more occasions; the acquisition rate was greatest in the first year. Monthly prevalence rates were 11%. Colonization with the initial strain persisted 1-5 months (median, 2). Children carried 1 predominant strain at a time but became colonized with up to 7 different strains (mean, 2.2). Children colonized with a single strain for < or = 2 months produced a greater nasopharyngeal secretory IgA to nontypeable H. influenzae response than did children colonized with different strains (log 2.35 +/- 0.68 vs. 1.89 +/- 0.25 U of P6 secretory IgA/ng/mL of total secretory IgA, P < .01). The duration of colonization with a strain and acquisition of a new strain may be affected in part by the local production of specific secretory IgA.

Publication types

  • Comparative Study
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Aging
  • Antibodies, Bacterial / blood*
  • Antibody Formation
  • Carrier State
  • Haemophilus Infections / epidemiology*
  • Haemophilus influenzae / classification
  • Haemophilus influenzae / immunology
  • Haemophilus influenzae / isolation & purification*
  • Humans
  • Infant, Newborn
  • Longitudinal Studies
  • Nasopharynx / microbiology*
  • Prospective Studies
  • Serotyping
  • Time Factors


  • Antibodies, Bacterial