Purpose: Immigrants and travelers may be sources of re-emergent infection in trachoma-endemic communities close to trachoma elimination. The primary objective of the A Surveillance and Azithromycin Treatment for Newcomers and Travelers Evaluation (ASANTE) trial was to determine whether a newcomer and traveler surveillance and treatment program in addition to annual mass drug administration (MDA) would reduce Chlamydia trachomatis infection when compared to MDA alone.

Methods: ASANTE was a randomized controlled trial in 52 communities in Kongwa, Tanzania. In 26 intervention communities, monitors treated everyone in new households, in-coming children and guardians in existing households, and all persons in households who had traveled between annual MDA events. A total of 26 usual practice communities received MDA only. Surveys of 100 1-9-year-olds from each community were conducted at baseline and every 6 months up to 2 years to assess clinical trachoma and C. trachomatis infection. Data on demographics and environmental factors were also collected.

Results: Mean prevalences of trachomatous inflammation - follicular (TF) and C. trachomatis were equivalent between the two arms (5.2% and 3.7% in intervention, and 4.9% and 3.6% in usual practice communities, respectively). Of 318 children with TF, 36.5% tested positive for C. trachomatis. TF prevalence was higher among households without a bicycle (p = 0.03) and lower with increasing child's age (p < 0.001). Infection prevalence was higher among households >30 minutes from water (p = 0.015). TF and infection prevalence decreased with increasing years of education (p = 0.004 and p = 0.002, respectively).

Conclusion: The ASANTE trial will inform guidance on the surveillance and treatment of persons traveling or newly arriving to communities hypo-endemic for trachoma.

• U10 EY022584/EY/NEI NIH HHS/United States