title: Surveillance of pneumococcal serotype 1 carriage during an outbreak of serotype 1 invasive pneumococcal disease in central Australia 2010-2012.
abstract: BACKGROUND
  An outbreak of serotype 1 invasive pneumococcal disease (IPD) occurred in Central Australia from October 2010 to the latter part of 2012. Surveillance of serotype 1 carriage was conducted to determine epidemiological features of asymptomatic carriage that could potentially be driving the outbreak.
  
  
  METHODS
  130 patients and accompanying persons presenting at Alice Springs Hospital Emergency Department consented to nasopharyngeal swab (NPS) collection. NPS were processed by standard methods, including culture, pneumococcal lytA quantitative real-time PCR, serotype 1-specific real-time PCR and multi-locus sequence typing (MLST).
  
  
  RESULTS
  Pneumococcal carriage was detected in 16% of participants. Carriage was highest in the under 10 year olds from remote communities surrounding Alice Springs (75%). Four NPS were positive for serotype 1 DNA by PCR; 3 were also culture-positive for serotype 1 pneumococci. Serotype 1 isolates had atypical colony morphology on primary culture. All serotype 1 carriers were healthy children 5 to 8 years of age from remote communities. By MLST, serotype 1 isolates were ST306, as were IPD isolates associated with this outbreak.
  
  
  CONCLUSIONS
  During an outbreak of serotype 1 ST306 IPD, carriage of the outbreak strain was detected in 3% NPS collected. All carriers were healthy children 5 to 8 years of age.
authors.forename: Jana Yr
authors.initials: JY
authors.lastname: Lai
authors.forename: Heather
authors.initials: H
authors.lastname: Cook
authors.forename: Teem-Wing
authors.initials: TW
authors.lastname: Yip
authors.forename: Jeanette
authors.initials: J
authors.lastname: Berthelsen
authors.forename: Stephen
authors.initials: S
authors.lastname: Gourley
authors.forename: Vicki
authors.initials: V
authors.lastname: Krause
authors.forename: Helen
authors.initials: H
authors.lastname: Smith
authors.forename: Amanda J
authors.initials: AJ
authors.lastname: Leach
authors.forename: Heidi
authors.initials: H
authors.lastname: Smith-Vaughan
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001315:Australia / Q000453:epidemiology; D002353:Carrier State / Q000453:epidemiology* / Q000382:microbiology*; D002648:Child; D002675:Child, Preschool; D004196:Disease Outbreaks; D062665:Epidemiological Monitoring; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D008875:Middle Aged; D009305:Nasopharynx / Q000382:microbiology; D011008:Pneumococcal Infections / Q000453:epidemiology* / Q000382:microbiology*; D013296:Streptococcus pneumoniae / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D055815:Young Adult