Water-borne infections are problems of immense proportion in India and other less developed countries. Eighty per cent of the diseases in these countries are linked with contaminated water. The list of water-borne diseases is given in the margin. Our health is affected by drinking polluted water either directly or by use of such water in cooking or for other personal purposes. The microorganisms of these diseases multiply in the body of the infected person. The infection is excreted with stool or urine. Therefore, improper disposal of human excreta is the chief cause of contamination of water of rivers, wells, lakes and shallow hand pumps and results in the spreading of these diseases. the extent of contamination in some Indian rivers estimated by fecal coliform.

It is indeed disheartening that after more than four decades of independence, our country has not succeeded in providing water, especially drinking water in rural and many urban areas, though we often hear claims of progress on all fronts. The sanitation and drinking water available to the people of India, Sri Lanka and Bangladesh. Many diseases like trachoma, scabies, skin sepsis and fungal infection are not water-borne but their incidence depends more on the quantity of water available for use.

Among the water related diseases diarrhea, jaundice, guinea worm, Japanese encephalitis, malaria, filariasis, knock-knees are prevalent in our country. The incidence of some of these has increased due to implementation of developmental projects, as you will study below.

So far, diarrhea has remained a permanent epidemic in the country. Its major victims are infants and children. Diarrhea along with malnutrition is a vicious killer. A part of the increase in the incidence of diarrhea amongst infants may also be due to the modern practice of bottle-feeding encouraged by advertisements of milk powder agencies.