Lecture (10): Water and public health Introduction:

Lecture (10): Water and public health Introduction: Lecture (10): Lecture objectives: By the end of this lecture students should be able to: To know the water and public health. To know the types of diseases related to water. To know the control & prevention of diseases related to water.

Lecture (10): Water and public health Introduction: The transmission of pathogens by water is a highly effective way of spreading infectious disease among large numbers of people. Today, waterborne disease outbreaks continue to be responsible for high morbidity and mortality worldwide.

Diseases Related to Water Water-borne Diseases Water-based Diseases Water-washed Diseases Water-related Diseases

Water-borne Diseases Diseases caused by ingestion of water contaminated by human or animal excrement, which contain pathogenic microorganisms Transmission occurs by drinking contaminated water, particularly contamination by pathogens transmitted from human excreta. These include most of the enteric and diarrheal diseases caused by bacteria and viruses worldwide.

Water-borne Diseases Include cholera, typhoid, amoebic and bacillary dysentery and other diarrheal diseases

Diarrheal Diseases Giardiasis (Protozoan) Cryptosporidiosis (Bacteria) Shigellosis (Bacteria) Viral Gastroenteritis (Virus) Stomach flu viruses Cryptosporidiosis-Milkawakee outbreak, the largest recorded waterborne outbreak in US history, affecting 25% of city’s population 1993 Campylobacter is the most common diarrheal illness in the US.

Water-borne Diseases In addition, water-borne disease can be caused by the pollution of water with chemicals that have an adverse effect on health. Fertilizers, pesticides, herbicides, or defoliant while treating farmland or spraying fruit trees

Arsenic Flouride Nitrates from fertilizers Carcinogenic pesticides (DDT) Lead (from pipes) Heavy Metals

Water-washed Diseases Diseases caused by poor personal hygiene and skin and eye contact with contaminated water

These include scabies, trachoma, typhus, and other flea, lice and tick-borne diseases.

Water-based Diseases Diseases caused by parasites found in intermediate organisms living in contaminated water

Includes Schistosomiasis and Dracunculiasis Snail (from egg to larvae to cervicariae) and crustacean

Water-related Diseases Water-related diseases are caused by insect vectors, especially mosquitoes, that breed or feed near contaminated water.

Water-related Diseases Include dengue, filariasis, malaria, onchocerciasis, trypanosomiasis and yellow fever

The Problem ~80% of infectious diseases > 5 million people die each year > 2 million die from water-related diarrhea alone Most of those dying are small children >5 million die by unsafe drinking water, lack of sanitation, and insufficient water for hygiene. At any given time, almost half of the people in developing countries suffer from water-related diseases. Collectively, they are more lethal than AIDS, according to WHO.

Other Consequences Lost work days Missed educational opportunities Official and unofficial healthcare costs Draining of family resources

Control & Prevention

Global Governments Communities Individuals

Education Issues Hygiene education Good nutrition Improvements in habitation and general sanitation Higher education training in water-related issues

General Guidelines Avoid contacting soil that may be contaminated with human feces. Do not defecate outdoors. Dispose of diapers properly.

Wash hands with soap and water before handling food. When traveling to countries where sanitation and hygiene are poor, avoid water or food that may be contaminated. Wash, peel or cook all raw vegetables and fruits before eating.