The war on water borne diseases is not a factor of science and technology entirely. It is a function of behavior change. It is about maintainable and sustainable high levels of sanitation. It is being able to bring water related diseases under control. This milestone is not easy to achieve because water related diseases are affected by many factors. Some factors predispose possibility of water borne disease.
The population of the world is increasing. In many undeveloped and developing countries, there is a high level of illiteracy. Poverty is also increasing at the same rate of the population increase. Population densities are high in slums and ghettos. For example, in Nairobi, Kenya, some of the slums are, Kibera slums the biggest in Africa, Kwa Njenga slums, Hillocks slums and Kwa Reuben slums. Many residents in the slums live on less than a dollar day. They consume water from boreholes that are dug along open trenches that empty their domestic waste into meandering tributaries that serve the slums. It implies the water drawn from the boreholes is contaminated by soluble substances presence in the human waste. This is like recycling domestic sewer wrongly. There are no lavatory facilities. The "flying toilets" are the order of the day. A flying toilet is a paper bag containing human waste or urine or mixture of both. There are no dumping sites for any domestic waste products. This scenario provides a good breeding site for mosquitoes and snails that cause malaria and bilharzias respectively. The environment also fosters a good environment for water related diseases. In many families, they don't have enough money to buy kerosene or paraffin to boil the water or at least buy chlorine to kill germs. They drink contaminated water and predispose themselves to diseases.
The residents may have required health education, but due to poverty, are they going to practice it? The diseases that affect them are cholera, dysentery, amoeba, bilharzias and malaria.
Many countries have a greater population living in the rural areas. These people are mainly the elderly that have low education. In many rural areas, many rivers are seasonal. Only a few families have toilet facilities. The highest population defecates in the neighboring forest closer to heir homes. When rain falls, these wastes are transported into tributaries where they dig wells. The water in these wells is used by their cattle, sheep or goats as well as human beings. It is forever contaminated. Residents who have used the contaminated water for long suffer bouts of diarrhea when they drink boiled water or chlorine treated water.
The developing countries are keen to industrialize. Their industries dispose their waste products into water. The harmful chemical substances can cause diseases directly by acting as a toxin, or affecting the normal metabolic processes or be incorporated into food chain by plants.
Deforestation has opened up virgin lands and the germs that were dormant are made active. Global warming also contributes to activating dormant germs. Ebola virus was detected in a spring water outlet in Congo, Africa. Many hot springs, geysers contain harmful substances that can enter the food chain and negatively affect normal body metabolic processes.