Diarrhoeal diseases are the second leading cause of death in children under five years of age, and are responsible for killing around 7,60,000 children every year all over the world. 2.2 million people die every year from diarrhoea caused by contaminated food and water globally. In the Asia-Pacific region, dehydration kills a child every seven minutes. Diarrhoea is also one of the main causes of dehydration--a condition that results when the body loses more water than it takes in--in small children. This imbalance disrupts the usual levels of salts and sugars present in the blood, which can interfere with the way the body functions.
Dehydration symptoms and signs depend on how much water you lose from your body. When you are mildly dehydrated (1-3% body weight loss), you will be probably thirsty and you might have a dry mouth. If you continue to lose water (4-6% body weight loss), your lips can become dry and you might feel tired and lightheaded. Your urine will probably become yellow. In severe dehydration (>6% body weight loss), you will likely be very thirsty and tired and you might have severe headache. Your heart will likely beat fast and you will excrete only a small amount of brown urine or no urine at all. When you lose more than 10% of body weight due to water loss you can lose consciousness or die.
Dehydration often causes only mild symptoms such as thirst and fatigue, but severe dehydration can lead to heat stroke, hypovolemic shock or even death. Chronic dehydration can increase the risk of kidney stones.
Severe dehydration (>10% loss of body weight) may result in a drop in blood volume which may result in an inadequate perfusion of the tissues. Early symptoms and signs of hypovolemic shock include anxiety, clammy skin and increased and weak pulse; late symptoms and signs include a drop of blood pressure, confusion or loss of consciousness. Hypovolemic shock needs to be treated promptly by intravenous saline infusion, otherwise it may result in death or permanent organ damage. If you suspect someone has symptoms or signs of hypovolemic shock, call an ambulance immediately.
Dehydration that results in greater than 2% loss of body weight can decrease physical performance. This may be important during a long-lasting exercise, such as marathon. Marathoners do not need to completely rehydrate themselves during the race but can stay mildly dehydrated and still keep their performance at the optimal level. In individuals with orthostatic hypotension--a drop of blood pressure upon standing--dehydration can worsen symptoms, for example, fainting after getting up in the morning. Drinking about 300 to 500 mL of water 15 minutes before getting out of bed can prevent dizziness.
If you are chronically dehydrated, you are at increased risk of developing kidney stones. Drinking sufficient amounts of water may help prevent kidney stones in some cases, but drinking large amounts of water in excess of your body needs may not have any further benefits.
Healthy, sedentary adults living in moderate climates may need 1.2 to 3.7 liters of water per day from beverages and foods combined. Active individuals in hot climates may need up to 10 liters of water per day.
A simpler and quicker, but less reliable, method to evaluate your hydration is to check your "skin turgor," that is your skin elasticity. Pinch and pull up the skin on the back of the hand (between the index and thumb) and release it. When you are well hydrated, the skin fold should flatten immediately (in less than 0.5 seconds) and when you are dehydrated, the skin fold may need more than a second to flatten.
Clean tap water my be an optimal beverage to prevent dehydration. When you suspect tap or well water might be contaminated by microbes, you can use bottled water. Tea and sport drinks may be also appropriate. Fruit juices and soft drinks usually contain a lot of sugar, which may promote weight gain if you drink them regularly.
Infants can get all the water they need from breast milk or formula, even in hot weather. Continuing with breastfeeding or formula during diarrhoea, even if a baby vomits to prevent malnutrition. Do not give plain water, tea or fruit juice to a dehydrated infant. Small children up to 4 years of age with diarrhoea need to get oral rehydration solution (ORS), which is available in market and drug stores.If you do not have ORS available or if a baby refuses to drink or eat, contact a doctor as soon as possible.
Per Medical Journal Armed Forces India, the main cause of diarrhoea in small children in India is gastroenteritis caused by drinking water contaminated by rotavirus from human feces. Per the researchers from Christian Medical College, Vellore, India, about 78,000 children under 5 years of age dies each year in India due to diarrhoea caused by rotavirus.
Rotavirus infections are much more common in formula-fed than in exclusively breastfed infants. Less common causes of diarrhoea in small children are infections with E.coli and other bacteria and parasites.
In March 2015, India launched its own rotavirus vaccine, which will be available for 1 USD; the vaccine is intended to be given orally in the first 6 months of life (4).
The other rotavirus vaccine that has already been available in India and many other countries is more than 70% effective in preventing rotavirus infection, according to Centers of Disease Control and Prevention in the United States; the protection against an infection lasts for at least about 1 year (5).
Dehydration in Infants and Toddlers Ehealthstar
Diarrhoeal disease World Health Organization
Corporate Support to Reduce Child Diarrhoeal Deaths GBC Health
PM Narendra Modi Launches Rotavirus Vaccine Developed in India NDTV
John J et al, 2014, Rotavirus gastroenteritis in India, 2011–2013: Revised estimates of disease burden and potential impact of vaccines ScienceDirect
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