The World Health Organization (WHO) Trachoma Program aims to eliminate trachoma as a public health concern by 2020?strictly speaking, this would be a control program, as infection is not being eliminated. The WHO recommends three to five annual mass azithromycin distributions to districts with measured prevalence of follicular trachoma (TF) above 10%, before re-assessment. However, despite as much as a decade of annual mass azithromycin distribution, TF prevalence in some districts of Amhara, Ethiopia remains over 25%. Elimination of infection, defined as reduction to zero in the incidence of infection in a specific defined geographic area, is feasible and may actually be more sustainable than control, as it may be less likely for infection to return in a community that has achieved zero new infections. Here, we propose to test two alternative antibiotic-based strategies for intensive targeting of core groups to achieve elimination at the kebele (administrative unit consisting of ~15 villages, or development teams) level. We propose a three-arm cluster randomized trial to test whether quarterly treatment of (1) all children aged 0-9 in the kebele plus annual mass azithromycin distribution or (2) all children aged 0-9 in the kebele with ocular C. trachomatis infection by PCR plus annual mass azithromycin distribution results in lower prevalence of ocular chlamydia and elimination in the kebele compared to (3) WHO-recommended annual mass azithromycin distribution alone. The results of this trial are expected to lead to evidence of alternative antibiotic-based strategies that may more reliably lead to complete elimination in geographic areas larger than a village.
Our proposal aims to test two intensive antibiotic-based strategies for the elimination of trachoma. The WHO hopes to eliminate trachoma as a public health problem (ie control trachoma) by 2020, however complete local elimination of the ocular strains that cause chlamydia may be feasible, and a more sustainable goal. Here we will test whether trachoma can be completely eliminated in a defined geographic area by quarterly treatment of a) all children in a community or b) all children with active ocular chlamydia infection determined by PCR, compared to the World Health Organization annual mass azithromycin distribution schedule. We will then use modeling techniques to optimize the minimum core group required for trachoma to lead to elimination of infection. We expect the results of this study will lead to enhanced intervention and antibiotic distribution schedules that will more predictably lead to trachoma elimination.