Our findings highlight several important health and WASH issues in remote areas of rural Nepal. Household and personal hygiene, including adequate handwashing, appropriate sanitation and access to regular and safely managed drinking water supply in the surveyed area, were inadequate. These poor WASH conditions were associated with diarrhoea, parasitic infections and nutritional deficiencies, which were highly prevalent among the surveyed children. More than half of the children in the study area suffered from undernutrition. This alarming health outcome was mainly linked to the low socio-economic status of the household, poor nutrition, and to the lack of regular deworming activities, but undernutrition was not significantly associated with poor WASH conditions.
The high prevalence of intestinal parasitic infections among children (51.1%) found in our study is similar to or higher than the rate reported in studies conducted in other parts of Nepal [30, 31, 57]. The higher infection rates could be explained by the fact that our study areas were located in extremely remote rural and hilly areas where accessibility was difficult and there was a lack of infrastructure, which together result in a low level of access to basic health and WASH services [30, 31, 57]. Our analysis revealed that children from households without latrines developing a parasitic infection relative to those with latrines were four times likely to have infected with an intestinal parasites. This indicates that the poor hygienic status observed in the pit latrines used by more than 94% of the households and lack of water to flush the toilets is a major risk factor in the transmission of parasites.
The effect of inadequate sanitary conditions on intestinal parasitic infections was also documented in a systematic review and meta-analysis . In our own study, we observed unsanitary practices that likely increased the presence of faecal pathogens in the household environment. For example, direct observation of toilets showed that many were stained with faecal matter. Additionally, the practice of keeping animals in or near the home, and sometimes bringing animals indoors overnight was observed in 59.7% of households. Such practices have been shown to increase exposure to faecal contamination in the household environment on other rural settings . A majority of the houses (84.1%) were equipped with mud floors inside the dwellings. These floors are regularly painted with cow dung—a practice that may also lead to a significant increase of fecal pathogens in the household. Children playing on the floor inside the house or around the house are at a high risk of ingesting pathogens present in such settings [59, 60]. In addition, food and drinking water were frequently kept uncovered in the kitchen and handled unhygienically, as described by studies conducted elsewhere [61, 62].
The cleanliness of caregivers’ hands was identified as a significant risk factor for children’s parasitic infections, suggesting that caregivers’ hands play a critical role in transferring parasites from the household environment to their children. There is strong evidence that a high load of pathogens in the household environment and inadequate handwashing cause an increased pathogen load on caregivers’ hands . We observed poor handwashing conditions, with 59.9% of households not having adequate infrastructure to wash hands and a limited presence of soap/water at the handwashing stations. Handwashing practices were largely insufficient, with 76% of the caregivers stating that they wash their hands with soap less than five times per day. The importance of clean hands to prevent parasitic infections is in agreement with previous studies conducted in eastern Nepal and Turkey where not using soap after defecation were significantly found to be associated with parasitic infection [31, 63]. The association between critical sanitation and hygiene factors and infections with intestinal parasites was also documented by studies conducted in other parts of Nepal [31, 64, 65].
Our study found that water quality at the point of consumption for the majority (78%) of households was in the intermediate or higher risk categories, according to WHO’s guidelines for drinking water quality . Even though most of all drinking water was collected from improved sources, high contamination levels were also measured at the source. This is similar to the findings of studies conducted elsewhere where improved sources were not necessarily safe  and contamination of the drinking water during transportation was reported [25, 67–70].
Surprisingly, despite the low quality of the water consumed, we did not find any association between drinking water quality and parasitic infections in the study households. We hypothesize that the transmission of pathogens through drinking water was minor compared to the high loads of pathogens existing in the household environment due to unhygienic sanitation, the practice of painting the earthen floors with cow dung and the presence of animal feces in and around the house. Contrary to this, two other recently conducted studies in Nepal identified the consumption of untreated water as a risk factor for infection with Giardia species [30, 65]. These studies, however, may have been conducted in a different, hygienically less challenging context.
We also examined the association between intestinal parasitic infections and different socio-demographic variables. Children belonging to households where caregivers could read but not write, or had not received any education, were at higher odds of intestinal parasitic infections compared to children whose caregivers could both read and write. These results are in line with those reported by Sah et. al (2013) which found higher prevalence of intestinal parasitic infection among children’s belonging to the parents who have lower education in comparison to those of the children’s with parents having higher education. .
The presence of livestock close to or inside the households, visible manure piles and the practice of spreading cow dung on the walls and floors of households likely pollute the household environment with faecal pathogens. This assumption is confirmed by several studies that associate the contamination of the floor with E. coli with the disposal of children’s faeces and the presence of animals in close proximity to the households. Kwong et. al reported that 35% of the children put their hands in their mouths after touching soil particles, putting them at risk of contamination . The studies conducted in India and Bangladesh [71–74] reported that faecal contamination in the domestic environment, including source and stored drinking water, hands and soil, was more prevalent from animals than from humans [75, 76]. We think that, similar to parasitic infections, a high load of pathogens in the household environments are due to unhygienic sanitation and inadequate hygiene practices, as well as the presence of animal faeces in and around the house, and that these were important risk factors for the diarrhoea burden in the study population [62, 73, 74, 76].
Interruptions of the water supply were associated with diarrhoea. Caregivers who reported more frequent interruptions to their drinking water systems that lasted more than a week, had 2.7 times higher odds of having children with diarrhoea. Underlying reasons could be the subsequent lack of water for hygienic practices or it could be that intermittent water services exhibit an increased risk of bacterial contamination in the system or it could be that the risk of pathogen infiltration is greater during such low pressure events in the piped network [77, 78]. Past research has reported that the households with the presence of E.coli in their drinking water were 3.6 times more likely to have children with diarrhoea than those that had water in compliance with WHO’s guidelines for drinking water quality . However, since only 5% of the households had water without any detectable E.coli, the association between diarrhoea and water quality was not significant in the multivariable regression model. Similar results were reported in other studies conducted in low- and middle-income countries, demonstrating that improvements in drinking water and sanitation are associated with decreased odds of diarrhoea [20, 79]. Specific improvements, such as the provision of high-quality piped water, sewer connections and the use of water filters, were associated with greater reductions in diarrhoea .
Our study found a high prevalence of undernutrition (55.5%) with stunting alone being at 44.5%. A reason for this could be that the study areas are located in food-scarce regions where agricultural activity has been affected by the impact of climate change, i.e. untimely heavy rainfall, droughts and hailstorms. Rural households in these areas are generally poor and their resilience and coping abilities to deal with reduced agricultural productivity is low. The vulnerability of low-income households towards increasing prices for food items has been demonstrated by Green et al . In our multivariable mixed logistic regression analyses, undernutrition was significantly associated with a household’s lower socioeconomic status, lower production of one’s own food, lower provision of supplemental food to children and irregular deworming activities.
Although the relation between undernutrition and parasitic infections is not well understood, undernutrition may be caused by recurring infections in the gut, which limit the proper absorption of calories and nutrients [81, 82]. Our findings on the association between undernutrition and intestinal parasitic infection are in agreement with studies conducted elsewhere [82, 83]. However, contrary to findings from a study conducted in Bangladesh, our study did not identify recent diarrhoea infection as a risk factor for undernutrition . As we collected data during a cross-sectional survey, we do not have any longitudinal information on the frequency and severity of diarrhoea cases occurring in the study population. We think that there is a high chance that chronic diarrhoea, as well as environmental enteropathy, are linked with undernutrition in our study site, but our data only refers to one point in time and, thus, cannot be confirmed [85–87]. WASH indicators were only significantly related with undernutrition in univariate analysis, but not in the multivariable logistic regression models. In univariate analysis, we found that low hygiene score in the kitchen, low personal hygiene of the caregiver and the child, and the presence of E.coli or total coliforms in the water source were associated with undernutrition.
Even though WHO recommends to start providing infants food in addition to breast milk from six months onwards , 97% of the children participating in the study received weaning food before this age. Multivariable mixed logistic regression analyses revealed considerably higher odds of undernutrition among children who were introduced with weaning food at an age of less than 6 months; however, the association was not significant. Nepal has a culture of starting to wean girls at five months, while boys usually receive weaning food at six months of age. The weaning practices before reaching six months of age may have caused some food borne infections and environmental enteropathy, resulting in nutritional deficiencies and undernutrition since the food provided to the infants was likely to be contaminated [82, 85]. We observed unhygienic handling and improper storage of food in the study areas—96% of the households did not have a refrigerator. Unsafe water was used to wash feeding and storage containers, unhygienic kitchen clothes were used to dry children’s utensils and caregivers did not wash their hands with soap while preparing and feeding children. In addition, 76.8% of the households had flies indoors and in their surroundings. The recurrent food borne infections may have resulted in nutritional deficiency, environmental enteropathy, and consequently undernutrition [4, 82, 85, 89]. Similar observations of unsafe WASH and inadequate food hygiene were reported in a study conducted in other parts of Nepal . A study from Mali showed that about 55% of complementary food samples used during weaning practices were infected with faecal coliform bacteria and might have been the main contributing factors to the poor nutritional status and infections among children under five years of age . A study conducted in Kenya reported an association between the early introduction of complementary foods to children less than six months of age and stunting . We found a significant protective association between children (six months to ten years) who received food supplements in addition to regular meals. This is in line with other studies that found a significant impact of nutrition on growth [92, 93]. However, surprisingly, we did not find a significant association between dietary diversity scores and undernutrition, which is in contrast to a study conducted in Indonesia that reported of higher dietary diversity scores associated with lower likelihood of child stunting . We assume that several confounding factors, such as household environment could mediate the effect of dietary diversity on undernutrition status, indicating the need for more depth research in this study population.
The prevalence of having at least one clinical sign for a nutritional deficiency was high (63.9%). Because there is a dearth of studies conducted on children having clinical signs of nutritional deficiencies in Nepal and other similar countries in terms of geography, income level of its population, literacy level and life expectancies, our results cannot be compared with other studies. The most frequently encountered nutritional deficency, pale conjunctiva (Niacine deficiency), which was found in 36.0% of children, can be related to the lack of animal proteins in diets.
Contrary to our results regarding risk factors associated with undernutrition, clinical signs of nutritional deficiencies were significantly associated with WASH conditions. Our analysis identified a significant protective association with handwashing, improved latrine cleanliness and lower number of total coliforms in the drinking water source. In contrast, signs of nutritional deficiencies were positively associated with keeping animals inside the house and the low personal hygiene of caregivers and of the children. Further in-depth research is required to provide more insight into these issues.
Our study has several limitations. First, this study is a cross-sectional survey conducted during spring time. Hence, the results reflect only one point of time. Although the association between diarrhoea, environmental enteropathy and undernutrition is well established in literature [81, 85, 87], recent diarrhoea infection in our study population was not identified as a risk factor for undernutrition. To assess this association, we propose to implement a controlled longitudinal study design that involves the collection of data on recurring chronic diarrhoea and which would measure markers of environmental enteropathy. Second, we consider some of our outcome variables such as diarrhoea to be subject to a seasonal effect [8, 95, 96]. Third, the findings presented in our study cannot be generalised to other rural areas of Nepal, as the study was conducted in an extremely remote setting characterized by exceptionally low access to basic services. Third, an anthropometric survey has certain limitations related to the inaccuracy of children’s dates of birth . Although, we checked available birth certificates to validate the reported ages, these certificates were not always forthcoming. Fourth, only one stool sample per participating child was examined by a double Kato-Katz thick smear, which likely led to an underestimation of the true prevalence of parasitic infections due to the low sensitivity of the Kato-Katz technique. Fifth, the information we obtained during the interviews was self-reported by the caregivers and may be subject to recall and respondent bias [8, 97].