title: Epidemiology of nasopharyngeal colonization with nontypeable Haemophilus influenzae in the first 2 years of life.
abstract: 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.
authors.affiliation: Division of Infectious Diseases, State University of New York at Buffalo, USA.
authors.forename: H
authors.initials: H
authors.lastname: Faden
authors.forename: L
authors.initials: L
authors.lastname: Duffy
authors.forename: A
authors.initials: A
authors.lastname: Williams
authors.forename: D A
authors.initials: DA
authors.lastname: Krystofik
authors.forename: J
authors.initials: J
authors.lastname: Wolf
mesh_terms: D000375:Aging; D000907:Antibodies, Bacterial / Q000097:blood*; D000917:Antibody Formation; D002353:Carrier State; D006192:Haemophilus Infections / Q000453:epidemiology*; D006193:Haemophilus influenzae / Q000145:classification / Q000276:immunology / Q000302:isolation & purification*; D006801:Humans; D007231:Infant, Newborn; D008137:Longitudinal Studies; D009305:Nasopharynx / Q000382:microbiology*; D011446:Prospective Studies; D012703:Serotyping; D013997:Time Factors
chemical_list: D000907:Antibodies, Bacterial