title: Ruminants Contribute Fecal Contamination to the Urban Household Environment in Dhaka, Bangladesh.
abstract: In Dhaka, Bangladesh, the sensitivity and specificity of three human, three ruminant, and one avian source-associated QPCR microbial source tracking assays were evaluated using fecal samples collected on site. Ruminant-associated assays performed well, whereas the avian and human assays exhibited unacceptable cross-reactions with feces from other hosts. Subsequently, child hand rinses (n = 44) and floor sponge samples (n = 44) from low-income-households in Dhaka were assayed for fecal indicator bacteria (enterococci, Bacteroidales, and Escherichia coli) and a ruminant-associated bacterial target (BacR). Mean enterococci concentrations were of 100 most probable number (MPN)/2 hands and 1000 MPN/225 cm(2) floor. Mean concentrations of Bacteroidales were 10(6) copies/2 hands and 10(5) copies/225 cm(2) floor. E. coli were detected in a quarter of hand rinse and floor samples. BacR was detected in 18% of hand rinse and 27% of floor samples. Results suggest that effective household fecal management should account not only for human sources of contamination but also for animal sources. The poor performance of the human-associated assays in the study area calls into the question the feasibility of developing a human-associated marker in urban slum environments, where domestic animals are exposed to human feces that have been disposed in pits and open drains.
authors.affiliation: Environmental and Water Studies, Department of Civil and Environmental Engineering, Stanford University , Stanford, California 94305, United States.
authors.forename: Angela R
authors.initials: AR
authors.lastname: Harris
authors.affiliation: Environmental and Water Studies, Department of Civil and Environmental Engineering, Stanford University , Stanford, California 94305, United States.|Woods Institute for the Environment, Stanford University , Stanford, California 94305, United States.
authors.forename: Amy J
authors.initials: AJ
authors.lastname: Pickering
authors.affiliation: Emmett Interdisciplinary Program in Environment and Resources, Stanford University , Stanford, California 94305, United States.
authors.forename: Michael
authors.initials: M
authors.lastname: Harris
authors.affiliation: icddr,b , Dhaka 1000, Bangladesh.
authors.forename: Solaiman
authors.initials: S
authors.lastname: Doza
authors.affiliation: icddr,b , Dhaka 1000, Bangladesh.
authors.forename: M Sirajul
authors.initials: MS
authors.lastname: Islam
authors.affiliation: icddr,b , Dhaka 1000, Bangladesh.
authors.forename: Leanne
authors.initials: L
authors.lastname: Unicomb
authors.affiliation: Woods Institute for the Environment, Stanford University , Stanford, California 94305, United States.
authors.forename: Stephen
authors.initials: S
authors.lastname: Luby
authors.affiliation: Environmental and Water Studies, Department of Civil and Environmental Engineering, Stanford University , Stanford, California 94305, United States.|Woods Institute for the Environment, Stanford University , Stanford, California 94305, United States.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Davis
authors.affiliation: Environmental and Water Studies, Department of Civil and Environmental Engineering, Stanford University , Stanford, California 94305, United States.
authors.forename: Alexandria B
authors.initials: AB
authors.lastname: Boehm
mesh_terms: D000818:Animals; D041963:Bacteroidetes; D001459:Bangladesh; D004784:Environmental Monitoring; D004926:Escherichia coli; D005243:Feces / Q000382:microbiology; D006801:Humans; D012418:Ruminants / Q000382:microbiology; D014871:Water Microbiology