In Pakistan contaminated water is one of the major sources of spread of diseases. In the developing countries like Pakistan, water-borne diseases cause four-fifths of all the illnesses, with diarrhea being the leading cause of childhood death.
Waterborne diseases are widespread in the country. Not only backward rural areas face this menace, but the people of congested urban centers also suffer from waterborne diseases, mainly due to poor municipal services and lack of awareness.
Cholera, Dengue, Diarrhea, Hepatitis, Malaria, Polio, Scabies and Typhoid include the waterborne diseases faced by Pakistani masses, and these disease could not be overcome without taking serious efforts by all stakeholders, especially the government.
Water-borne diseases are any illness caused by drinking water contaminated by human or animal feces, which contain pathogenic micro-organisms. The full picture of water-associated diseases is complex for a number of reasons. Over the past decades, the picture of water-related human health issues has become increasingly comprehensive, with the emergence of new water-related infection diseases and the re-emergence of ones already known.
Data are available for some water, sanitation and hygiene related diseases, which include salmonellosis, cholera, shigellosis, but for others such malaria, schistosomiasis or the most modern infections such legionellosis or SARS CoV the analyses remain to be done.
The burden of several disease groups can only partly be attributed to water determinants. Even where water plays an essential role in the ecology of diseases, it may be hard to pinpoint the relative importance of aquatic components of the local ecosystems.
The common water-related diseases include anemia, arsenicosis, ascariasis, botulism, campylobacteriosis, cholera, cryptosporiodiosis, cyanobacterial toxins, dengue, diarrhea, dracunculiasis, fluorosis, giardiasis, hepatitis, hookworm infection, Japanese encephalitis, lead poisoning, legionellosis, leptospirosis, lymphatic filariasis, malaria, malnutrition, methaemoglobinemia, onchocerciasis, polio, ring worm or tinea, scabies, schistomiasis, trachoma, trichuriasis and typhoid.
The global picture of water and health has a strong local dimension with some 1.1 billion people still lacking access to improved drinking water sources and some 2.4 billion to adequate sanitation. World Health Organisation (WHO) estimates indicate that world-wide over 2 billion people are infected with schistosomes and soil transmitted helminthes and 300 million of these suffer serious illness as a result.
Malaria kills over a million people every year and a large percentage of them are under five as well, mainly in African areas south of the Sahara. In 2001 the estimated global burden of malaria amounted to 42.3 million Disability Adjusted Life Years (DALYs), constituting 10 per cent of Africa's overall disease burden. Malaria causes at least 396.8 million cases of acute illness each year. Pregnant women are the main adult risk group. As one of the major public health problems in tropical countries, it has been claimed that malaria has reduced economic growth in African countries by 1.3 per cent each year over the past 30 years.
An estimated 246.7 million people world-wide are infected by schistomiasis, and of these 20 million suffer severe consequences of the infection, while 120 million suffer milder symptoms. An estimated 80 per cent of transmission takes place in African areas south of the Sahara. Diarrhea occurs world-wide and causes 4 per cent of all deaths and 5 per cent of the health loss to disability.
Contaminated water could be disinfected. Water disinfecting means the removal, deactivation or killing of pathogenic micro-organisms.
Micro-organisms are destroyed or deactivated, resulting in termination of growth and reproduction. When micro-organisms are not removed from drinking water, drinking water usage will cause people to fall ill. Sterilisation is a process related to disinfecting. However, during the sterilisation process all present micro-organisms are killed, both harmful and harmless micro-organisms. Disinfection can be attained by means of physical or chemical disinfectants. The agents also remove organic contaminants from water, which serve as nutrients or shelters for micro-organisms.
Disinfectants should not only kill micro-organisms. Disinfectants must also have a residual effect, which means that they remain active in the water after disinfection. A disinfectant should prevent pathogenic micro-organisms from growing in the plumbing after disinfecting, causing the water to be re-contaminated.
For chemical disinfecting of water the following disinfectants can be used: Chlorine (Cl2), Chlorine dioxide (ClO2), Hypo chlorite (OCl-), Ozone (O3), Halogens: bromine (Br2), iodene (I), Bromine chloride (BrCl), Metals: copper (Cu2+), silver (Ag+), Kaliumpermanganate (KMnO4), Fenols, Alcohols, Soaps and detergents, Kwartair ammonium salts, Hydrogen peroxide, and several acids and bases For physical disinfecting of water the following disinfectants can be used: Ultraviolet light (UV), Electronic radiation, Gamma rays, Sounds, and Heat.-PPI