title: Impact of more than a decade of pneumococcal conjugate vaccine use on carriage and invasive potential in Native American communities.
abstract: BACKGROUND
  We assessed the impact of 12 years of pneumococcal conjugate vaccine (PCV7) use on pneumococcal nasopharyngeal carriage and serotype-specific invasive disease potential among Native Americans.
  
  
  METHODS
  Families were enrolled in a carriage study from 2006 to 2008; nasopharyngeal specimens and risk factor information were collected monthly for 7 visits. Pneumococcal carriage prevalence was compared with that before (1998-2000) and during (2001-2002) PCV7 introduction. We compared invasive disease incidence and carriage prevalence before and after PCV7 introduction to estimate changes in serotype-specific invasive potential.
  
  
  RESULTS
  We enrolled 1077 subjects from 302 households. There was an absolute reduction in carriage prevalence of 8.0% (95% confidence interval [CI], 4.5%-11.4%) in children aged <5 years and 3.1% (95% CI, 1.1%-5.1%) in adults. In children aged <5 years, vaccine-serotype carriage prevalence decreased by 22.8% (95% CI, 20.1%-25.3%), and nonvaccine serotype (NVT) increased by 15.9% (95% CI, 12.4%-19.3%). No significant change was detected in serotype-specific invasive potential after PCV7 introduction.
  
  
  CONCLUSIONS
  Pneumococcal carriage prevalence decreased in all ages since PCV7 introduction; vaccine-serotype carriage has been nearly eliminated, whereas the prevalence of NVT carriage has increased. The increase in the NVT invasive disease rate seems to be proportional to the increase in colonization prevalence.
authors: Center for American Indian Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland 21205, USA.
authors: Jennifer R
authors: JR
authors: Scott
authors: Eugene V
authors: EV
authors: Millar
authors: Marc
authors: M
authors: Lipsitch
authors: Lawrence H
authors: LH
authors: Moulton
authors: Robert
authors: R
authors: Weatherholtz
authors: Mindy J
authors: MJ
authors: Perilla
authors: Delois M
authors: DM
authors: Jackson
authors: Bernard
authors: B
authors: Beall
authors: Mariddie J
authors: MJ
authors: Craig
authors: Raymond
authors: R
authors: Reid
authors: Mathuram
authors: M
authors: Santosham
authors: Katherine L
authors: KL
authors: O'Brien
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002353:Carrier State / Q000453:epidemiology*; D016009:Chi-Square Distribution; D002648:Child; D002675:Child, Preschool; D016001:Confidence Intervals; D005260:Female; D006801:Humans; D015994:Incidence; D007198:Indians, North American; D008297:Male; D008875:Middle Aged; D009305:Nasopharynx / Q000382:microbiology; D022242:Pneumococcal Vaccines; D011018:Pneumonia, Pneumococcal / Q000453:epidemiology* / Q000473:pathology / Q000517:prevention & control; D015995:Prevalence; D012307:Risk Factors; D012703:Serotyping; D013296:Streptococcus pneumoniae; D014611:Vaccination; D055815:Young Adult
chemical_list: D022242:Pneumococcal Vaccines