| Literature DB >> 34079208 |
Kaitlin J Mattos1,2, Laura Eichelberger2, John Warren2, Aaron Dotson3, Millie Hawley4, Karl G Linden1.
Abstract
Household water, sanitation and hygiene (WASH) practices in remote, rural, and unpiped communities are likely to impact exposure to pathogens beyond the fecal-oral transmission routes that are typically prioritized in WASH interventions. We studied 43 homes in two remote, rural, unpiped communities in Alaska to evaluate seasonal water haul, water sources, water quality, and water reuse, as well as greywater and human waste disposal over 1 year. Hauled quantities of water reportedly ranged from 3.0 to 5.4 gallons per capita per day (gpcd) depending on the community and season. Natural, untreated water sources contributed 0.5-1.1 gpcd to household water availability. Reported quantities of water hauled were significantly correlated with total water storage capacity in the home. Total coliforms were detected in 30-60% of stored household water samples from treated and untreated sources, and total coliform counts were significantly higher in specific sources and during specific seasons. Exposure to pathogens during periods of low water access, from untreated water reuse, from greywater disposal and from human waste disposal are important pathways of disease transmission in these remote, rural, unpiped communities. We discuss intermediate steps that can be taken at the household and community levels to interrupt exposure pathways before piped infrastructure is installed. This model of examining specific household practices to determine transmission routes can be applied to other remote communities or unique conditions to aid in the recommendation of targeted WASH interventions. © Kaitlin J. Mattos, et al., 2021; Published by Mary Ann Liebert, Inc.Entities:
Keywords: WASH; pathogen exposure; remote; rural; unpiped
Year: 2021 PMID: 34079208 PMCID: PMC8165469 DOI: 10.1089/ees.2020.0283
Source DB: PubMed Journal: Environ Eng Sci ISSN: 1092-8758 Impact factor: 1.907
Population Characteristics from Two Study Communities— One in the Interior and One in the Northwest Region of Alaska
| Study population characteristics | Interior community | Northwest community | Total |
|---|---|---|---|
| Number of HH in study (% of total HH) | 19 (51%) | 24 (40%) | 43 (44%) |
| Total no. of HH in community | 37 | 60 | 97 |
| Average no. of persons per home | 2.9 | 5.2 | 4.2 |
| Average no. of children per home | 0.8 | 2.2 | 1.6 |
| Adults in study HH who graduated high school/total no. of adults in study HH, | 27/29 (93) | 42/63 (67) | 69/92 (75) |
| HH who own home, | 12 (63) | 16 (67) | 28 (65) |
| HH with access to functioning vehicle, | 16 (84) | 13 (54) | 29 (67) |
| Median age of respondent | 47 | 55 | 54 |
| female respondents, | 14 (58) | 18 (53) | 32 (55) |
HH, household.
Reported Quantity of Water Hauled to the Home in Gallons Per Capita Per Day and as a Percent of the WHO Recommendation for Intermediate Water Access (13.2 gpcd, Howard and Bartram 2003)
| Interior gpcd (mean ± SD) | Northwest gpcd (mean ± SD) | Total gpcd (mean ± SD) | Total water hauled as % of WHO rec | |
|---|---|---|---|---|
| Water hauled to the home–all sources | ||||
| Fall | 3.3 ± 4.9 ( | 4.4 ± 5.8 ( | 4.0 ± 5.4 ( | 30% |
| Winter | 3.5 ± 3.2 ( | 3.9 ± 4.1 ( | 3.8 ± 3.7 ( | 29% |
| Spring | 5.4 ± 3.1 ( | 3.4 ± 3.5 ( | 3.9 ± 3.4 ( | 30% |
| Summer | 3.0 ± 1.8 ( | 5.1 ± 6.6 ( | 4.3 ± 5.5 ( | 37% |
| Water hauled to the home–treated watering point (WTP) only | ||||
| Fall | 1.9 ± 1.6 ( | 4.4 ± 5.8 ( | 3.5 ± 4.9 ( | 27% |
| Winter | 2.7 ± 1.9 ( | 3.9 ± 4.0 ( | 3.6 ± 3.5 ( | 27% |
| Spring | 3.5 ± 2.0 ( | 3.4 ± 3.5 ( | 3.4 ± 3.0 ( | 26% |
| Summer | 2.2 ± 1.2 ( | 3.5 ± 3.2 ( | 3.0 ± 2.7 ( | 23% |
“All sources” includes treated community watering point (wtp), store-bought bottled water, rainwater, snow melt, and river water.
SD, standard deviation; WTP, water treatment plant. N refers to number of households with data available for a given season.
FIG. 1.Water sources used in the home varied by season and differed between the two communities. “WTP” refers to the community's watering point at the centralized water treatment plant.
FIG. 2.Variation in household water haul by community and season, considering all water sources versus community water treatment plant (“WTP”) only. Boxes represent interquartile range (IQR). Horizontal mid-line represents median value. Vertical lines show values less than 1.5 times the IQR. Asterisks denote outliers outside of 1.5 times the IQR above the upper quartile and below the lower quartile.
Total Coliform and Escherichia coli Concentrations from Household Stored Water Samples (N) in Different Seasons and from Different Water Sources in Two Communities
| Number of samples | Total coliforms | Total coliforms | |||
|---|---|---|---|---|---|
| Mean ± SD, MPN/100 mL | 95% CI, MPN/100 mL | % positive ( | % positive ( | ||
| All samples | 309 | 45 ± 179 | 25–65 | 30 (92) | 2 (5) |
| Samples by source | |||||
| WTP | 258 | 39 ± 164 | 19–59 | 27 (69) | ≤1 (2) |
| Rain | 31 | 81 ± 250 | 0–172 | 55 (17) | 10 (3) |
| River | 15 | 69 ± 261 | 0–213 | 20 (3) | 0 (0) |
| Snow | 5 | 76 ± 141 | 0–251 | 60 (3) | 0 (0) |
| Samples by season | |||||
| Winter | 66 | 21 ± 125 | 0–52 | 20 (13) | 0 (0) |
| Spring | 70 | 58 ± 215 | 7–109 | 27 (19) | 0 (0) |
| Summer | 92 | 72 ± 228 | 5–94 | 33 (30) | 5 (5) |
| Fall | 81 | 23 ± 99 | 1–45 | 37 (30) | 0% (0) |
Greywater Disposal Locations from Unpiped Households (n) in Two Communities by Season
| No. of households | ≤5 m away from home or underneath home | ≥5 m away from home | Underground in pit or outhouse |
|---|---|---|---|
| Fall ( | 23 | 3 | 4 |
| Winter ( | 19 | 7 | 2 |
| Spring ( | 21 | 5 | 3 |
| Summer ( | 27 | 4 | 3 |
FIG. 3.Number of bag-days (no. of toilet bags sitting outside times number of days) that human waste sits outside of the home before being hauled away for disposal. Results are self-reported from households using bucket latrines (“honeybuckets”) in two communities by season. Y-axis is truncated and does not display highest y-values. Boxes represent interquartile range (IQR). Horizontal mid-line represents median value. Vertical lines show values less than 1.5 times the IQR. Asterisks denote outliers outside of 1.5 times the IQR above the upper quartile and below the lower quartile.
FIG. 4.A model of pathogen exposure describing multiple transmission routes identified in this study. This model can be used to implement targeted WASH interventions that can efficiently improve community health and wellbeing.