title: Current epidemiology and trends in invasive Haemophilus influenzae disease--United States, 1989-2008.
abstract: BACKGROUND
  With the introduction of Haemophilus influenzae serotype b (Hib) conjugate vaccines, there has been a dramatic reduction of Hib disease in young children and the epidemiological trends of invasive H. influenzae have shifted.
  
  
  METHODS
  Data were collected from active surveillance for invasive H. influenzae disease conducted through Active Bacterial Core surveillance sites during 1989-2008.
  
  
  RESULTS
  During 1999-2008, the estimated mean annual incidence of H. influenzae infection was 1.62 cases per 100 000 population; 15.3% of cases were fatal. Incidence was higher among adults aged ≥65 years, compared with other age groups. The largest burden of disease among children aged <5 years was in infants aged <1 year; many of these cases occurred during the first month of life in preterm or low-birth weight infants. An estimated 10% of the total burden of disease among children aged <5 years occurred in American Indian and Alaska Native children. During 1989-2008, 7559 cases of H. influenzae disease were reported from Active Bacterial Core surveillance sites. Small increases in the incidence of serotypes a, e, and f were observed during 1989-2008. The largest of these increases was in serotype f and was primarily among adults aged ≥18 years.
  
  
  CONCLUSIONS
  Since the introduction of Hib conjugate vaccines, the incidence of invasive disease caused by H. influenzae in the United States has decreased dramatically; however, a considerable burden of non-Hib disease is still present in the oldest and youngest age groups. There is no evidence of substantial replacement disease with non-b serotypes in young children in the United States.
authors.affiliation: Division of Bacterial Diseases, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia 30333, USA. macneil@cdc.gov
authors.forename: Jessica R
authors.initials: JR
authors.lastname: MacNeil
authors.forename: Amanda C
authors.initials: AC
authors.lastname: Cohn
authors.forename: Monica
authors.initials: M
authors.lastname: Farley
authors.forename: Raydel
authors.initials: R
authors.lastname: Mair
authors.forename: Joan
authors.initials: J
authors.lastname: Baumbach
authors.forename: Nancy
authors.initials: N
authors.lastname: Bennett
authors.forename: Ken
authors.initials: K
authors.lastname: Gershman
authors.forename: Lee H
authors.initials: LH
authors.lastname: Harrison
authors.forename: Ruth
authors.initials: R
authors.lastname: Lynfield
authors.forename: Susan
authors.initials: S
authors.lastname: Petit
authors.forename: Arthur
authors.initials: A
authors.lastname: Reingold
authors.forename: William
authors.initials: W
authors.lastname: Schaffner
authors.forename: Ann
authors.initials: A
authors.lastname: Thomas
authors.forename: Fatima
authors.initials: F
authors.lastname: Coronado
authors.forename: Elizabeth R
authors.initials: ER
authors.lastname: Zell
authors.forename: Leonard W
authors.initials: LW
authors.lastname: Mayer
authors.forename: Thomas A
authors.initials: TA
authors.lastname: Clark
authors.forename: Nancy E
authors.initials: NE
authors.lastname: Messonnier
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D002675:Child, Preschool; D005006:Ethnicity; D005260:Female; D006192:Haemophilus Infections / Q000453:epidemiology* / Q000382:microbiology* / Q000401:mortality; D018073:Haemophilus Vaccines / Q000008:administration & dosage / Q000276:immunology; D006193:Haemophilus influenzae / Q000145:classification* / Q000302:isolation & purification*; D006801:Humans; D015994:Incidence; D007223:Infant; D008297:Male; D008875:Middle Aged; D012703:Serotyping; D014481:United States / Q000453:epidemiology; D055815:Young Adult
chemical_list: D018073:Haemophilus Vaccines