Water, sanitation and hygiene: needs
In a series of publications on water, sanitation and hygiene, Bartram and Cairncross (2010) provided an overview of WSH practices and needs worldwide \cite{Bartram:PlosMed:2010}. Water, sanitation and health are three components of public health and diarrhoea and subsequent malnutirition adds considerably to burden of diseases, mortality, morbidity and national costs. Following TB, malaria, and HIV/AIDS, diarrhoea is the next major killer disease for children particularly in the developing countries and contribute to about 4 million deaths worldwide. Diarrhoea also leads to malnutrition due to loss of water and nutrients. Poor hand washing leads to lack of use of water to wash face and eyes, as a result, trachoma infections are common in countries where hand washing and face washing are not practiced. Improper sanitation or removal of faeces promote hookwork and other intestinal nematode infections such as Ascaris infection. The intestinaal parasitic infections then lead to further worsening of malnutrition. Besides these, due to abdominal pain and other symptoms, children skip schools sometimes for days, and this in turn lead to loss of time. In addition to loss of time due to infections, there is also loss of time for women who have to fetch water over long distances, and people who have to look for places to defecate. About 800 million people would still defecate out in the open even if the millenial development goals are met to 100% and with over population, new goals will need to be drafted as even with attainment of these goals, there would still be people who would not have piped water supply and safe disposal of faeces.
Developed countries are not exempt from such considerations either. Although the coverage of safe disposal of faeces is higher in the developed world, there is still no guarantee as to the quality of the sanitation and how the risk of faecal contamination of the drinking water sources are avoided or addressed. Several water borne diseases have been reported worldwide in countries such as Canada; in
New Zealand, in 2016, a waterborne disease outbreak occurred in Havelock North and was attributed to faceal contamination of water. As in developing countries, hand washing promotion in developed countries have shown reduction by 50% of gastrointestinal infections in child care centres and in Australia about 42% caregivers were found to practice regular hand washing.
Water supply, sanitation (disposal of faeces) and promotion of hand washing with water and soap requires intersectoral collaboration and active government intervention. This is particularly problematic in poor and underdeveloped regions in the world or lower socioeconomic strata, yet you will see that while government could have assisted with piped water supply delivery systems or help with building of latrines, such effects are lacking. Health sector professionals need to engage with other sectors to promote these services.
Role of water for health and other purposes
Hunter et.al. (2010) have discussed the role of water supply in a wider global context \cite{Hunter:PlosMed:2010}. Water supply systems for sustaining health has six qualities (quality of the water being provided, quantity of the water at the rate of 1.5 l/person/day for basic activities of sanitation and cooking, and 50 l/person/day for washing and other activities, and on an average of 1000 cu.m per year per head; access to the water must be less than 1000 m, reliability of the water must be that good quality of water to be supplied throughout the year, cost of the water to the user should be such that it can be borne easily, and the ease of management of the water supply should not be too hard. Good quality adequate water supply (and lack of it) has health consequences that are both acute and chronic: acute health effect is diarrhoea, and chronic health effects are not only chronic diarrhoea, malnutrition and downstream effects, but also poisoning from heavy metals and chemicals (arsenic and fluoride); however, diarrhoeal diseases are highlighted most often.
These are problems with both developed and developing countries. For developing countries, the problems are in ensuring availability and maintenance of fresh adquate water supply; for developed world, the issues are dissociation between health care aspects of water supply; in the past, medical community and public health community would take a bigger responsibility and role in ensuring availablity of good quality adequate water supply; now, water provision is more technical and as a result, many authorities who provide water do not have sufficient knowledge about the health consequences of drinking water supply: when that happens, outbreaks occur even in developed countries.
There are issues around water supply provisions and there are disparities there. We know that under five mortality is correlated with low per capita GDP and low percentage of improved water supply. We also know that per capita GDP is associated with improved water supply to some extent. We know for instance that low developed parts of the world are often reliant on ground water as they may not have adequate rainfall the year round, unlike most developed countries. As rainfall helps to replenish groundwater, the risks of depleiton of groundwater is higher in poor and developing countries.
Further, there is a cost of ownership and provision of high quality water to households. However, as most families and households are used to not pay anything yet they obtain low quality water from sources that are not improved such as tanks; as a result, they are loathe to pay when improved water supply provisions are made available. Therefore there is a case for making high quality water supply to them at modest cost sharing options. This is all the more needed as provision of good quality piped water systems will not only help to reduce diarrhoeal and other diseases, but they will also help to alleviate the issues around sanitation.