Fecal Contamination and Diarrheal Pathogens on Surfaces and in Soils among Tanzanian Households with and without Improved Sanitation

• Published in: Environmental science & technology 2012-06, Vol.46 (11), p.5736-5743
• Main Authors: Pickering, Amy J, Julian, Timothy R, Marks, Sara J, Mattioli, Mia C, Boehm, Alexandria B, Schwab, Kellogg J, Davis, Jennifer
• Format: Article
• Language: English
• Subjects: Air. Soil. Water. Waste. Feeding; Applied sciences; Atmospheric pollution; Biological and medical sciences; Colony Count, Microbial; Contamination; Crops, Agricultural - microbiology; Diarrhea; Diarrhea - microbiology; Disease transmission; E coli; Enterococcus - growth & development; Environment. Living conditions; Environmental Monitoring; Escherichia coli - genetics; Escherichia coli - growth & development; Exact sciences and technology; Family Characteristics; Feces; Feces - microbiology; Genes, Bacterial - genetics; Households; Humans; Indoor pollution and occupational exposure; Medical sciences; Pathogens; Pollution; Public health. Hygiene; Public health. Hygiene-occupational medicine; Rotavirus; Sanitation; Sequence Analysis, DNA; Soil Microbiology; Surface Properties; Tanzania; Viruses
• ISSN: 0013-936X; 1520-5851
• DOI: 10.1021/es300022c

Little is known about the extent or pattern of environmental fecal contamination among households using low-cost, on-site sanitation facilities, or what role environmental contamination plays in the transmission of diarrheal disease. A microbial survey of fecal contamination and selected diarrheal pathogens in soil (n = 200), surface (n = 120), and produce samples (n = 24) was conducted in peri-urban Bagamoyo, Tanzania, among 20 households using private pit latrines. All samples were analyzed for E. coli and enterococci. A subset was analyzed for enterovirus, rotavirus, norovirus GI, norovirus GII, diarrheagenic E. coli, and general and human-specific Bacteroidales fecal markers using molecular methods. Soil collected from the house floor had significantly higher concentrations of E. coli and enterococci than soil collected from the latrine floor. There was no significant difference in fecal indicator bacteria levels between households using pit latrines with a concrete slab (improved sanitation) versus those without a slab. These findings imply that the presence of a concrete slab does not affect the level of fecal contamination in the household environment in this setting. Human Bacteroidales, pathogenic E. coli, enterovirus, and rotavirus genes were detected in soil samples, suggesting that soil should be given more attention as a transmission pathway of diarrheal illness in low-income countries.