title: Can we stop mass drug administration prior to 3 annual rounds in communities with low prevalence of trachoma?: PRET Ziada trial results.
abstract: OBJECTIVE
  The World Health Organization recommends at least 3 annual mass drug administrations (MDAs) of azithromycin in places where the prevalence of follicular trachoma (FT) is greater than 10%. However, stopping MDA prior to 3 rounds, if monitoring indicates an absence of infection with Chlamydia trachomatis even if FT persists, may be more cost-effective.
  
  
  OBJECTIVE
  To determine the prevalence of infection in communities randomized to 3 rounds of annual MDAs with azithromycin compared with communities randomized to a stopping rule, where MDA could cease if the infection rate was low. DESIGN A 1:1 community randomized trial comparing usual care with a cessation rule. The Partnership for the Rapid Elimination of Trachoma-Ziada Trial was conducted from February 1, 2010, through September 1, 2011.
  
  
  METHODS
  Sixteen communities in Tanzania with trachoma prevalence rates between 10% and 20%.
  
  
  METHODS
  A total of 100 children aged 5 years or younger randomly drawn from each community. Children had to reside in an eligible community, have no ocular condition that prevented trachoma grading or ocular specimen collection, and have a guardian who could provide consent for participation.
  
  
  METHODS
  Cessation of MDA with azithromycin if the community had no infection in their sample at 6 months or 18 months.
  
  
  METHODS
  The prevalence of C trachomatis at 18 months.
  
  
  RESULTS
  None of the intervention communities met criteria to stop MDA based on the 6-month or 18-month survey; all, as well as the usual care communities, were scheduled for a third MDA round. There was no difference in infection (2.9% vs 4.7%; P = .25) between the usual care and cessation rule communities at 18 months.
  
  
  CONCLUSIONS
  In this setting, communities with low (10%-20%) initial prevalence of active trachoma did not have MDA stopped before 3 annual rounds on the basis of monitoring for infection. Infection with C trachomatis in communities with average trachoma rates at 12% to 13% cannot be eliminated before 3 rounds of MDA with azithromycin.
  
  
  BACKGROUND
  clinicaltrials.gov Identifier: NCT00792922.
authors: Dana Center for Preventive Ophthalmology, USA.
authors: Jithin
authors: J
authors: Yohannan
authors: Beatriz
authors: B
authors: Munoz
authors: Harran
authors: H
authors: Mkocha
authors: Charlotte A
authors: CA
authors: Gaydos
authors: Robin
authors: R
authors: Bailey
authors: Thomas A
authors: TA
authors: Lietman
authors: Thomas
authors: T
authors: Quinn
authors: Sheila K
authors: SK
authors: West
mesh_terms: D000900:Anti-Bacterial Agents / Q000008:administration & dosage*; D017963:Azithromycin / Q000008:administration & dosage*; D002648:Child; D002675:Child, Preschool; D002690:Chlamydia Infections / Q000188:drug therapy / Q000453:epidemiology* / Q000382:microbiology; D002692:Chlamydia trachomatis / Q000302:isolation & purification; D003153:Community Health Services; D017714:Community-Acquired Infections / Q000188:drug therapy / Q000453:epidemiology* / Q000382:microbiology; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D008403:Mass Screening; D017410:Practice Guidelines as Topic; D015995:Prevalence; D013636:Tanzania / Q000453:epidemiology; D014141:Trachoma / Q000188:drug therapy / Q000453:epidemiology* / Q000382:microbiology; D016896:Treatment Outcome; D028761:Withholding Treatment; D014944:World Health Organization
chemical_list: D000900:Anti-Bacterial Agents; D017963:Azithromycin
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