Diarrheal diseases

Diarrhea itself is not a disease, rather it is a symptom of many diseases. 

Diarrheal diseases are the world's second biggest killer of children (after acute respiratory infections).  Every year they kill more than two million people - mostly children under the age of five.

There are approximately four billion cases of diarrhea each year which are caused by more than 100 different bacteria, protozoa or viruses. They are spread through:

• Contaminated water
• Contaminated food
• Unsanitary disposal of human waste
• Poor personal hygiene

Diarrhea causes the rapid depletion of water and sodium in the sufferer. If these are not replaced quickly, the body starts to become dehydrated and the body's salt balance is severely damaged.

If more than 10% of the body's fluid is lost the sufferer dies. Children who are malnourished suffer the most, becoming even weaker and more malnourished as diarrhea progresses.

The three most deadly diarrheal diseases are cholera, bacillary dysentery and typhoid. Others include amoebic dysentery, giardiadis, salmonella, camplyobacteriosis and cryptosporidiosis.

All of these diseases can be stopped by the same preventative methods, so if the three most deadly were eliminated the others would be too.

Cholera is a disease that can cause large epidemics killing the young, the weak and the old. It is known and feared throughout the developing world. The bacteria, which can last for up to three weeks in soil, is spread by contaminated water, food and occasionally by person to person contact.

Sudden large outbreaks are usually caused by a contaminated water supply.

Effect on health: The bacteria attaches to the wall of the small intestine where it multiplies and produces a poisonous chemical. This poison prevents the body from taking water from the intestine and so the body rapidly dehydrates.

Up to 14 liters of diarrhoea can by passed in one day. The lack of water in the body causes the blood pressure to drop and the kidneys to fail. Death occurs within 24 hours.

Bacillary dysentery is more severe than amoebic dysentery. It is estimated that 140 million people are infected each year resulting in around 300,000 deaths annually, mostly among children under the age of five.

It is caused by Shigella bacteria which enter the body through contaminated drinking water, food or flies which then infect the large intestine. It can be spread between people - especially young children.

Effect on health: Symptoms can include fever, abdominal pain, nausea, cramping and severe, frequent, watery diarrhea that can contain blood, mucus and pus.

Typhoid fever affects 17 million people worldwide every year, with approximately 600,000 deaths. It is contracted when people drink water or eat food infected with a bacterium called Salmonella Typhi found in human waste.

It has been virtually eliminated in the western world through sanitary facilities.

Effect on health: Typhoid fever is recognized by the sudden onset of sustained fever, severe headache, nausea and constipation. Later it is accompanied by diarrhea, a rash and other complications which can include intestinal hemorrhaging or perforation.

Giardia normally produces a mild bowel infection, with symptoms of nausea, vomiting, diarrhea, malaise, and poor appetite, its effects can be much worse in developing countries. Where people have nutrient-poor diets it can become chronic, suppressing adequate calorie intake and leading to weight loss, and in some cases death.

Rotavirus causes severe diarrhea and vomiting and is estimated to kill around 600,000 children under five every year in developing countries. It is highly infectious and spreads when children are exposed to contaminated water, food or fecal matter.

Prevention of diarrheal diseases

Diarrheal diseases can be prevented by improving access to clean water and sanitation so that bacteria cannot re-enter water supplies. Hygiene education plays a vital role in informing communities about safe hygiene.

The keys to prevention are clean water, clean hands at meal times and uncontaminated food. Hygiene education where communities learn about the benefits of using latrines, keeping food and water clean, cooking food thoroughly, washing and peeling fruit and vegetables, washing hands with soap before touching food and the sanitary disposal of human waste can all help prevent diarrhea and contamination.

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