Survey of trachoma within school students in the state of Roraima, Brazil

Abstract

<h4>Purpose</h4>Trachoma, a blinding conjunctivitis, is the result of repeated infection with Chlamydia trachomatis. There are no recent data for the state of Roraima, Brazil, where it was thought that trachoma no longer existed. These data are derived from school children sampled in this state, with additional data collected from the contacts of children with trachoma.<h4>Design</h4>A population-based cross-sectional study with random sampling of students in grades 1 through 4 of all public schools within municipalities where the human development index was less than the national average in 2003. The sample was stratified according to population size.<h4>Participants</h4>A sample size of 7200 was determined and a total of 6986 (93%) students were examined, along with an additional 2152 contacts.<h4>Methods</h4>All students were examined for trachoma according to World Health Organization criteria. Demographic data and contact information also was collected. The family and school contacts of students with trachoma then were located and examined.<h4>Main outcome measures</h4>Prevalence and grade of trachoma, age, gender, race, and municipality location.<h4>Results</h4>The overall prevalence of trachoma was 4.5% (95% confidence interval [CI], 3.7%-5.3%), but there were municipalities within the state where the prevalence of inflammatory trachoma was more than 10%. The prevalence was greater in rural areas (4.9%; 95% CI, 3.7%-6.0%) compared with urban areas (3.9%; 95% CI, 2.9%-4.9%). Living in indigenous communities was associated with trachoma (odds ratio, 1.6; 95% CI, 0.9-2.6). An additional 2152 contacts were examined, and the overall trachoma prevalence was 9.3% (95% CI, 8.1-10.5).<h4>Conclusions</h4>Trachoma continues to exist in Roraima, Brazil, where there are municipalities with a significant prevalence of disease. The indigenous population is highly mobile, crossing state and international borders, raising the possibility of trachoma in neighboring countries. Trachoma prevalence among the contacts of students with trachoma was higher than the school population, highlighting the importance of contact tracing.<h4>Financial disclosure(s)</h4>The author(s) have no proprietary or commercial interest in any materials discussed in this article.