title: Preliminary evidence that synanthropic flies contribute to the transmission of trachoma- causing Chlamydia trachomatis in Latin America.
abstract: Synanthropic flies have been shown to be important mechanical vectors of Chlamydia trachomatis, which causes trachoma. However entomological studies have not been forthcoming in Latin America. This study assesses the relationship between household dipteran fly densities and active childhood trachoma in a village on Marajó Island, Pará state, Brazil. For 78 households, members were examined for signs of trachoma, relative abundance of potential trachoma vectors (Diptera, Chloropidae and Diptera, Muscidae) was quantified by trap counts, and additional measures of household hygiene associated with C. trachomatis transmission were assessed. Active childhood trachoma prevalence was 24.1% (45/187), present in 46.2% of sampled households with evidence of case clustering. Childhood prevalence was positively associated with increased fly densities, whereas indirect measures of sanitary conditions (latrine ownership and perceived importance of flies) showed a protective effect. This study indicates that C. trachomatis can be transmitted by synanthropic flies in this region of Latin America.
authors.affiliation: Department of Biological Sciences, University of Warwick, Coventry, UK.
authors.forename: Lucy A
authors.initials: LA
authors.lastname: Reilly
authors.forename: Joana
authors.initials: J
authors.lastname: Favacho
authors.forename: Lourdes M
authors.initials: LM
authors.lastname: Garcez
authors.forename: Orin
authors.initials: O
authors.lastname: Courtenay
mesh_terms: D000293:Adolescent; D000704:Analysis of Variance; D000818:Animals; D002648:Child; D002675:Child, Preschool; D002692:Chlamydia trachomatis; D005260:Female; D006801:Humans; D006920:Hygiene; D007300:Insect Control; D007303:Insect Vectors / Q000382:microbiology*; D007843:Latin America / Q000453:epidemiology; D008297:Male; D009117:Muscidae / Q000382:microbiology*; D011156:Population Density; D011576:Psychodidae / Q000382:microbiology*; D012111:Residence Characteristics; D012307:Risk Factors; D014141:Trachoma / Q000453:epidemiology / Q000635:transmission*