ABSTRACT
The common wisdom is that a trachoma program cannot eliminate ocular chlamydia from a community, just reduce infection to a level where blindness would be minimal. We describe the success of multiple mass antibiotic treatments, demonstrating that complete elimination of infection may be an attainable goal in an area with modest disease.
Subject(s)
Trachoma/drug therapy , Trachoma/epidemiology , Anti-Bacterial Agents/administration & dosage , Anti-Bacterial Agents/therapeutic use , Azithromycin/administration & dosage , Azithromycin/therapeutic use , Child , Child, Preschool , Chlamydia trachomatis/isolation & purification , Female , Humans , Infant , Male , Nepal/epidemiology , Prevalence , Time Factors , Trachoma/prevention & controlABSTRACT
The WHO has initiated a global program to eliminate trachoma. This program includes mass antibiotic administrations to reduce the prevalence of Chlamydia trachomatis, the causative agent in trachoma. DNA amplification tests are the most sensitive methods to diagnose C. trachomatis infection, but are expensive and not typically performed in trachoma-endemic areas. Trachoma programs use clinical examination to determine which communities and which individuals within communities would benefit from antibiotic treatment, so understanding the relationship between clinical activity and chlamydial infection is important. In this study, we determine what percent of individuals with clinically active trachoma are infected with chlamydia in low prevalence communities of China and Nepal (with <10% clinical activity in children), and compare this against a high prevalence community of Nepal (with >30% clinical activity in children). In the low prevalence areas, only 8% clinically active cases had evidence of chlamydia. In the high prevalence community, 70% of clinically active cases harbored chlamydia. These results imply that clinical activity is less indicative of infection at a lower prevalence. In the context of a trachoma program, both clinically active cases and the community as a whole may stand to benefit less from antibiotic treatment in lower prevalence areas.
Subject(s)
Trachoma/diagnosis , Trachoma/epidemiology , Adolescent , Adult , Aged , Child , Child, Preschool , China/epidemiology , Chlamydia trachomatis/genetics , Chlamydia trachomatis/isolation & purification , Conjunctiva/microbiology , DNA, Bacterial/analysis , Female , Humans , Infant , Male , Middle Aged , Nepal/epidemiology , Polymerase Chain Reaction , Prevalence , Trachoma/microbiologyABSTRACT
We assessed how much of the observed decline in the prevalence of trachoma in a district of Western Nepal was due to an antibiotic treatment program and how much to an underlying secular trend outside of the program. Although antibiotic treatments clearly have an effect at 6 months, we were unable to show that this effect persisted at 12 months; in fact, long-term gains may be due to a secular trend in the area.
