Study of Three Alternatives for Mass Treatment in Trachoma Villages of Tanzania
Condition: Trachoma
MeSH terms: Trachoma
Study type: Interventional
Phase: Phase 4

Summary: 
      After single, yearly, mass treatment of communities with azithromycin for active trachoma,
      what is the added effectiveness for reduction of trachoma and ocular C. trachomatis infection
      at one, two, and three years, relative to the added costs, of community-based surveillance
      and treatment of cases of severe trachoma (TI) semi-annually or every 4 months?
    

Detailed description: 
      An important component of a trachoma control program is the effective use of antibiotics,
      particularly azithromycin, to reduce the pool of chlamydial ocular infection in the
      communities. A reduction in the pool of infection will reduce the likelihood of transmission
      and, coupled with effective hygiene and environmental changes, theoretically lead to
      reduction in disease to the point where active trachoma is no longer a public health problem.
      Our previous experience with the use of azithromycin for community treatment has shown that
      even with high rates of coverage, hyperendemic communities will start to experience
      re-emergent trachoma following treatment by one year. Therefore, it is urgent to determine if
      there is another treatment strategy for these villages to keep the pool of infection low, and
      eventually eliminated.A combination approach consisting of mass treatment at yearly intervals
      and surveillance with a targeted treatment approach in the interim period may be effective in
      maintaining the low rate of re-emergent disease.We propose to test the cost-effectiveness of
      three alternative strategies for the frequency of provision of azithromycin, in the context
      of the Tanzanian National Trachoma Control Program. The strategies have been developed to
      build on the epidemiological knowledge of trachoma in this area, to be locally appropriate in
      terms of feasibility and personnel, and to be consistent with the goal of enhancing community
      control of the program.

      A total of nine villages in the Kongwa district of Tanzania will be randomized to one of
      three groups (a total of three villages per group). The nine villages, with active trachoma
      rates in pre-school children of 50% or greater, would be slated for enrollment in the
      National Program, but not currently receiving treatment. Surveys for active trachoma status
      would be carried out in 300 randomly selected, children ages 1-7 years (pre-school)in each
      village at baseline, at 6 months post mass treatment, and at one, two, and three years post
      baseline. The following treatment strategies will be used:

      Control villages: Usual practice: The three villages randomized to this arm would receive
      mass treatment of the community once a year as part of the Tanzania National Trachoma Control
      program.

      Intervention 1. Usual practice plus community surveillance for TI cases and treatment at 6
      months: The three villages randomized to this arm would receive mass treatment, similar to
      the usual practice arm, but in addition, would have a cadre of community volunteers, trained
      to recognize TI. They will screen their neighborhoods, examining all pre-school children and
      mothers, and arrange with the health worker for another round of treatment for TI cases and
      their families at 6 months, and 18 months post baseline.

      Intervention 2: Usual practice plus community surveillance for TI cases and treatment every 4
      months: The three villages randomized to this arm would have an approach identical to
      intervention 1, but with surveillance and treatment of TI cases at 4 and 8 months instead of
      at 6 months.For the second year, they would have surveillance and treatment at 6 months.

      Cost data on the community surveillance and treatment program will be collected throughout
      the first year. Analyses will focus on the additional benefit on reduction in prevalence of
      trachoma, and ocular C. trachomatis infection, at one, two, and three years of the two
      alternative strategies, relative to yearly mass treatment alone, and the cost-effectiveness
      of the three strategies.
    

Intervention name(s): community surveillance and re-treatment
Intervention type(s): Behavioral
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Double
Primary purpose: Treatment
Keywords: trachoma; chlamydia trachomatis; surveillance; azithromycin