title: Detection of Chlamydia trachomatis ocular infection in trachoma-endemic communities by rRNA amplification.
abstract: OBJECTIVE
  Trachoma remains the leading infectious cause of blindness worldwide. The World Health Organization (WHO) recommends mass antibiotic distributions in its strategy to eliminate blinding trachoma. To determine the most effective antibiotic treatment strategy, it is essential to have a diagnostic test that can correctly measure the true status of ocular Chlamydia trachomatis infection in individuals, particularly after treatment. A newer ribosomal ribonucleic acid (rRNA)-based amplification test was compared with the current DNA-based polymerase chain reaction (PCR) for the detection of C. trachomatis.
  
  
  METHODS
  An rRNA-based assay and PCR were performed on swab specimens taken from the right upper tarsal conjunctiva of 240 children aged 1 to 5 years living among 16 endemic villages in the Gurage Zone, Ethiopia.
  
  
  RESULTS
  The rRNA-based test detected ocular C. trachomatis infection in 142 (59%) subjects compared with 67 (28%) detected by PCR (McNemar's test, P < 0.0001). The rRNA-based test gave positive results for all subjects who were positive by PCR and detected infection in 75 (31%) additional subjects.
  
  
  CONCLUSIONS
  The rRNA-based test appears to have significantly greater sensitivity than PCR for the detection of ocular C. trachomatis infection in children in trachoma-endemic villages. The increased sensitivity of the rRNA-based test may be due to its ability to detect low levels of C. trachomatis infection in individuals, which can occur especially after antibiotic treatment. Data from past studies in which PCR was used to assess the prevalence of infectious trachoma after community-wide antibiotic treatments could have underestimated the true prevalence of infection.
authors.affiliation: F. I. Proctor Foundation, University of California, San Francisco, San Francisco, CA 94143, USA.
authors.forename: Jon L
authors.initials: JL
authors.lastname: Yang
authors.forename: Kevin C
authors.initials: KC
authors.lastname: Hong
authors.forename: Julius
authors.initials: J
authors.lastname: Schachter
authors.forename: Jeanne
authors.initials: J
authors.lastname: Moncada
authors.forename: Takele
authors.initials: T
authors.lastname: Lekew
authors.forename: Jenafir I
authors.initials: JI
authors.lastname: House
authors.forename: Zhaoxia
authors.initials: Z
authors.lastname: Zhou
authors.forename: Melissa D
authors.initials: MD
authors.lastname: Neuwelt
authors.forename: Tina
authors.initials: T
authors.lastname: Rutar
authors.forename: Colleen
authors.initials: C
authors.lastname: Halfpenny
authors.forename: Neelima
authors.initials: N
authors.lastname: Shah
authors.forename: John P
authors.initials: JP
authors.lastname: Whitcher
authors.forename: Thomas M
authors.initials: TM
authors.lastname: Lietman
mesh_terms: D002675:Child, Preschool; D002692:Chlamydia trachomatis / Q000235:genetics / Q000302:isolation & purification*; D003228:Conjunctiva / Q000382:microbiology; D019353:Endemic Diseases; D005002:Ethiopia / Q000453:epidemiology; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D021141:Nucleic Acid Amplification Techniques / Q000379:methods*; D016133:Polymerase Chain Reaction; D012329:RNA, Bacterial / Q000032:analysis*; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D014141:Trachoma / Q000175:diagnosis* / Q000453:epidemiology* / Q000382:microbiology
chemical_list: D012329:RNA, Bacterial; D012336:RNA, Ribosomal, 16S