==== Summary ====
[[File:Under 5 y-o child mortality.png|thumb|right|200px|Under Children under 5 year-years old child : mortality.]]This article is based on a [http://www.susana.org/en/resources/library/details/2163 factsheet] that provides an overview on existing evidence and remaining research gaps regarding the link between inadequate sanitary conditions and its underestimated impact on undernutrition and stunting, particularly for children under five years of age. It is a clear plea for more rigorous research, policy coherence and cooperation between Health and Nutrition, WASH, Mental Health, Care Practices and Food Security sectors, and the need to adequately address and consider WASH as an integral part of nutrition interventions. It particularly highlights the impact of WASH interventions on mothers and children’s children (under five years of age) nutritional and health status. An estimated 30% of all children in low-income countries suffer from undernourishment and WASH services can help to alleviate this:<br/>
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''More than 3.5 million mothers and children under five die unnecessarily each year due to the underlying causes of undernutrition, and millions more children are permanently disabled by the physical and mental effects of a poor dietary intake in the earliest months of life.''<br/>The Lancet’s Series on Maternal and Child Undernutrition, 2013.<br/>
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''Child health, nutrition, growth, and development are interlinked, and are influenced by the hygiene of the immediate environment in which the baby begins to explore the world. In addition to expanding the scope of interventions, it is also important to broaden the conceptual structure of WASH as an aspect of child nutrition and development interventions, and not simply as the sum of toilets, caregiver hand washing, and water purification. WASH should be defined holistically as broadly encompassing the hygiene-related aspects of the physical and behavioral environment in which children are being raised.''<br/>Ngure et al., WASH and ECD: Making the Links, 2014. Ann. N.Y. Acad. Sci. 1308 (2014) 118–128 C 2014 New York Academy of Sciences <br/>
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*Growth faltering is strongly associated with diarrheal disease cases (Weitz, 2011).<br/>
*There is strong evidence of a positive impact of WASH interventions on child infections (Fewtrell Review , 2005).<br/>
*Improved WASH conditions can reduce parasitic intestinal infections such as worm infestation that impacts nutritional status (Pruss-Ustun, 2006).<br/>
*Symptoms from nematode parasites (such as hookworm) include loss of blood and consequently increased anemia prevalence leading to chronic fatigue and stunting (Black, 2013).<br/>
*High pathogen environments induce recurring infections in the gut that limit proper absorption of nutrients, known as Environmental Enteropathy (Humphrey, 2009).
==== Main WASH routines ====
[[File:5 A's framework.png|thumb|right|200px|5-A's framework]]
The 5 A’s is a new framework of analysis for undernutrition malnutrition:
*Availability: Nutritious food should be readily available and sufficient.
*Absorption: Much of food that is ingested is not absorbed due to infections that cause damage to small intestine leading to reduced capacity to absorb nutrients. Diarrhea cases dehydrate and evacuate nutrients unabsorbed.
*Antibodies: Producing antibodies to fight infections diverts nutritional energy from growth to defense.
*Allopathogens: Numerous other FTIs take their toll, including Hepatitis A, B and E, typhoid fever, etc.
The last three “A’s” can be impacted positively by improved WASH facilities and services. Nutrition interventions typically focus on quantity and quality of food, feeding programs, and issues of governance and rights. This new framework of 5 A’s presents a more comprehensive analysis of undernutrition with attention to the role of fecal-transmitted infections (FTI) represented in the last 3 A’s. Among FTIs, diarrhea incidences received the most attention, but environmental enteropathy (damage of small intestine wall due to ingestion of fecal bacteria) is also nutritionally very significant. Recent research establishes the direct link with undernutrition and open defecation (OD) as well as its associated unhygienic conditions and practices.