title: The easiest children to reach are most likely to be infected with ocular Chlamydia trachomatis in trachoma endemic areas of Niger.
abstract: BACKGROUND
  Control programs for trachoma use mass antibiotic distributions to treat ocular Chlamydia trachomatis in an effort to eliminate this disease worldwide. To determine whether children infected with ocular Chlamydia are more likely to present later for examination than those who are uninfected, we compare the order of presentation for examination of children 0-5 years, and the presence of ocular Chlamydia by PCR in 4 villages in Niger where trachoma is endemic.
  
  
  METHODS
  We conducted a cluster-randomized, controlled trial where 48 randomly selected villages in Niger are divided into 4 study arms of different mass treatment strategies. In a substudy of the main trial, we randomly selected 1 village from each of the 4 study arms (4 total villages) and we evaluated the odds of ocular Chlamydia versus the rank order of presentation for examination and laboratory assessment before treatment was offered.
  
  
  RESULTS
  We found the odds of harboring ocular Chlamydia dropped by more than 70% from the first child examined to the last child examined (OR 0.27, 95% CI 0.13-0.59, P = 0.001) in the 4 randomly selected villages. We found the odds of active trachoma dropped by 80% from the first child examined to the last child examined (OR 0.20, 95% CI 0.10-0.4, P<0.0001) in the 48 villages in the main trial.
  
  
  CONCLUSIONS
  This study demonstrates that even if the WHO recommended 80% treatment coverage is not reached in certain settings, children 0-5 years with the greatest probability of ocular Chlamydia have higher odds of receiving attention because they are the first to present. These results suggest there may be diminishing returns when using scarce resources to track down the last few children in a mass treatment program.
  
  
  BACKGROUND
  ClinicalTrials.gov NCT00792922.
authors: Programme National de Lutte Contre la Cecité, Niamey, Niger.
authors: Abdou
authors: A
authors: Amza
authors: Boubacar
authors: B
authors: Kadri
authors: Baido
authors: B
authors: Nassirou
authors: Sun N
authors: SN
authors: Yu
authors: Nicole E
authors: NE
authors: Stoller
authors: Satasuk J
authors: SJ
authors: Bhosai
authors: Zhaoxia
authors: Z
authors: Zhou
authors: Charles E
authors: CE
authors: McCulloch
authors: Sheila K
authors: SK
authors: West
authors: Robin L
authors: RL
authors: Bailey
authors: Jeremy D
authors: JD
authors: Keenan
authors: Thomas M
authors: TM
authors: Lietman
authors: Bruce D
authors: BD
authors: Gaynor
mesh_terms: D000900:Anti-Bacterial Agents / Q000008:administration & dosage*; D001431:Bacteriological Techniques / Q000379:methods; D002675:Child, Preschool; D002692:Chlamydia trachomatis / Q000235:genetics / Q000302:isolation & purification*; D019353:Endemic Diseases; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D009548:Niger / Q000453:epidemiology; D010342:Patient Acceptance of Health Care / Q000706:statistics & numerical data*; D016133:Polymerase Chain Reaction / Q000379:methods; D014141:Trachoma / Q000175:diagnosis* / Q000188:drug therapy* / Q000453:epidemiology
chemical_list: D000900:Anti-Bacterial Agents