Waterborne disease

Waterborne or water related diseases encompass illnesses resulting from both direct and indirect exposure to water, whether by consumption or by skin exposure during bathing or recreational water use.

It includes disease due to water-associated pathogens and toxic substances. These diseases are directly related to environmental deterioration and pollution. Despite the continued efforts to maintain water safety, waterborne outbreaks are still reported globally.

Many waterborne pathogens can also be acquired by consuming contaminated food or beverages, from contact with animals or their environment, or through person-to-person spread.

Cholera and typhoid fever are classical examples of waterborne diseases, where only a few highly infectious pathogens are needed to cause severe diarrhea. Shigellosis, hepatitis A, amoebic dysentery and other gastrointestinal diseases can also be waterborne.

Fecal contamination of water is globally recognized as one of the leading causes of waterborne diseases.

While diarrhea and vomiting are the most commonly reported symptoms of waterborne illness, other symptoms can include skin, ear, respiratory, or eye problems.

Diarrhea occurs worldwide and causes 4% of all deaths and 5% of health loss due to disability. Diarrhea is the passing of loose or liquid stools more frequently than is normal for the individual. It is primarily a symptom of gastrointestinal infection. Depending on the type of infection, the diarrhea may be watery (for example in cholera) or passed with blood (in dysentery for example).

Disease which are often water-borne:
*Cholera
*Typhoid
*Infectious hepatitis
*Giardiasis
*Amoebiasis
*Dracunculiasis
Waterborne disease

Food-borne pathogenic bacteria: Vibrio cholerae

Vibrio cholerae belonging to O1 and O139 sero-groups cause cholera, a life threatening diarrheal disease that spreads through consumption of water and food contaminated with the pathogen. Vibrio cholerae O1 is the causative agent of cholera.

Although Vibrio cholerae is a human pathogen, the bacteria are part of the normal aquatic flora in estuarine and brackish waters and thus are able to persist in the environment outside human host.

Cholera was originally endemic in eastern India. Up to 1960, it had extended from India in six pandemics over the world.

Vibrio cholerae is a motile rod with a single polar, sheathed flagellum. It can grow in peptone water with 6% NaCl.

Although cholera is considered a waterborne disease, there is an evidence indicates the importance of food, particularly seafood, in the transmission of cholera.

The physicochemical characteristics of foods that support survival and growth of Vibrio cholerae O1 are high moisture content, neutral or alkaline pH, low temperature, high organic content and an absence of other competing bacteria.

Pathogenic vibrios are capable of producing three clinical manifestations of infection: gastroenteritis, soft tissue infections and systemic infections in including bacteremia.
Food-borne pathogenic bacteria: Vibrio cholerae

Waterborne disease microorganisms

Waterborne disease causing organisms are for the most part in three general categories of microorganism. i.e. bacteria, protozoa and viruses. They made the water unsafe for human consumption.

In most cases, they originate for human and/or animal fecal wastes.

Waterborne viral agents and the diseases they cause include poliomyelitis virus (polio) and hepatitis A virus (hepatitis).

Waterborne bacteria and the diseases they cause include Escherichia coli (gastroenteritis), Legionella spp. (legionellosis), Salmonella typhi (typhoid fever), Shigella spp. (shigellosis or bacillary dysentery) and Vibrio cholerae (cholera).

A waterborne disease outbreak is a water exposure in which at least two persons have been epidemiologically linked to recreational or drinking water by location, time, and illness.

During late nineteenth and early twentieth century there were two waterborne diseases that posed the greatest threat to the American population: typhoid fever and diarrhea.

Typhoid fever is caused by Salmonella typhi, a bacterium that can survive only in human hosts and lives in the intestinal tract. People typically contracted the disease by drinking contaminated water.

More broadly, water caused diseases also include water-washed diseases caused by poor personal hygiene and skin or eye contact with contaminated water, water based diseases caused by parasites found in intermediate organisms living in water and water related diseases caused by insect vectors which breed in water.  
Waterborne disease microorganisms