Survey of trachoma within Brazilian students in the state of Roraima - Medina, Norma Helen; Lopes, Maria de Fatima; Cardoso, Maria Regina Alves; Luna, Expedito José de Albuquerque; Koizumi, Inês; Durkin, Shane; Freitas, Helen; Maurício, Maria Angela (Congress of the International Society Geographical & Epidemiological Ophthalmology (ISGEO), 2010)