title: Risk Factors for Pneumococcal Colonization of the Nasopharynx in Alaska Native Adults and Children.
abstract: BACKGROUND
  Alaska Native children have high invasive pneumococcal disease (IPD) rates, and lack of in-home running water has been shown to have a significant association with infection. Pneumococcal conjugate vaccines reduced IPD; however, this population saw substantial replacement disease and colonization with nonvaccine serotypes. We evaluated risk factors for nasopharyngeal pneumococcal colonization in Alaska Native adults and children.
  
  
  METHODS
  We conducted annual surveys from 2008 through 2011 of residents of all ages in 8 rural Alaskan villages. Interviews were conducted, medical charts were reviewed, and nasopharyngeal swabs were cultured for Streptococcus pneumoniae. Multivariate logistic regression models were developed for 3 age groups (under 10 years, 10-17 years, and 18 years and older) to determine risk factors for colonization.
  
  
  RESULTS
  We obtained 12 535 nasopharyngeal swabs from 4980 participants. Our population lived in severely crowded conditions, and 48% of households lacked in-home running water. In children <10 years, colonization was associated with lack of in-home running water, household crowding, and more children in the home. Pneumococcal vaccination status was not associated with colonization. In older children and adults, increased number of persons in the household was associated with pneumococcal colonization.
  
  
  CONCLUSIONS
  Higher colonization prevalence may partially explain increased IPD rates seen in those lacking in-home water services. Improving availability of sanitation services and reducing household crowding may reduce the burden of IPD in this population.
authors.affiliation: Department of Internal Medicine-Pediatrics, Harvard-Massachusetts General Hospital, Boston.
authors.forename: Jonathan
authors.initials: J
authors.lastname: Reisman
authors.affiliation: Arctic Investigations Program, Division of Preparedness and Emerging Infections, National Center Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Anchorage, Alaska.
authors.forename: Karen
authors.initials: K
authors.lastname: Rudolph
authors.affiliation: Arctic Investigations Program, Division of Preparedness and Emerging Infections, National Center Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Anchorage, Alaska.
authors.forename: Dana
authors.initials: D
authors.lastname: Bruden
authors.affiliation: Arctic Investigations Program, Division of Preparedness and Emerging Infections, National Center Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Anchorage, Alaska.
authors.forename: Debby
authors.initials: D
authors.lastname: Hurlburt
authors.affiliation: Arctic Investigations Program, Division of Preparedness and Emerging Infections, National Center Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Anchorage, Alaska.
authors.forename: Michael G
authors.initials: MG
authors.lastname: Bruce
authors.affiliation: Arctic Investigations Program, Division of Preparedness and Emerging Infections, National Center Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Anchorage, Alaska.
authors.forename: Thomas
authors.initials: T
authors.lastname: Hennessy
keywords: Streptococcus pneumoniae; pneumococcal colonization; vaccine; water