Diseases & Conditions
A condition that usually causes diarrhea, caused by an infection with either viruses, bacteria, or parasites. How long the child is sick depends on the germ and the child. In cases of mild diarrhea caused by a virus, the diarrhea should pass after a few days; the child should recover completely with supportive care, rest, and plenty of ﬂuids.
In developed countries such as the United States, outbreaks of diarrhea are more often linked to contaminated water supplies, improperly processed or preserved foods, or person-to-person contact in child-care centers. Diarrheal infections are contagious and can spread from child to child via dirty hands, direct contact with fecal matter, contaminated food or water, and some pets.
Viruses One of the most common diarrheal illnesses in American children is ROTAVIRUS, so widespread that almost all American children have had a rotavirus infection by the time they are four or ﬁve years old, although not all children show symptoms. The viruses can live for signiﬁcant periods of time on toys and surfaces in play areas. Rotavirus commonly causes outbreaks of diarrhea during the winter and early spring months, especially in child-care centers and chil-dren’s hospitals. Hand-washing in these places is very important to stop the rapid spread of outbreaks of rotavirus.
Another viral infection that causes diarrhea in children, especially during the summer months, is from ENTEROVIRUSES, particularly group A and B COXSACKIE VIRUSES.
Bacteria At least 13 different types of bacteria can cause diarrheal infections, including Salmonella, Shigella, Escherichia coli, and Campylobacter. In the United States, Salmonella bacteria cause between one and ﬁve million cases of diarrheal illness each year and are responsible for more than half the nation’s food poisonings. Shigella bacteria, which commonly spread from person to person, are especially dangerous because they attack the intestinal wall and cause ulcers that bleed. As few as 10 Shigella bacteria are enough to cause an infection, so shigellosis spreads easily in families, hospitals, and child-care centers.
Five different classes of E. coli cause diarrheal infection in children, most often during their ﬁrst few years of life. E. coli bacteria can cause diarrheal illness either by directly attacking the intestinal wall or by producing a toxin that irritates the intestines. One of the most dangerous E. coli infections is E. coli 0157:H7, which produces a toxin that can lead to HEMOLYTIC UREMIC SYNDROME—a severe illness that can seriously damage many organs and cause intestinal bleeding. Most E. coli infections are spread through contaminated food or water, especially in undercooked beef in hamburgers.
Parasitic infection Parasitic infections associated with gastrointestinal symptoms in the United States are most commonly caused by Giardia, which is easily spread through contaminated water supplies and human contact. This parasite can be spread in water parks and pools because it is resistant to chlorine treatment. It can also be transmitted through children’s “touch tanks” in aquariums and museums. Bathing in and drinking water from contaminated streams or lakes can also lead to infection. GIARDIASIS can cause chronic diarrhea and malabsorption of food. Cryptosporidium, another parasitic organism, is another common cause of gastrointestinal illness in children that often occurs in diarrhea epidemics in child-care centers.
Incubation times before symptoms appear vary depending on the germ causing the infection. For example, the Shigella incubation period is usually 16 to 72 hours, but viral incubation periods can range from four to 48 hours. Parasitic infections generally have longer incubation periods; Giardia has an incubation period of one to three weeks.
Crampy, abdominal pain is followed by diarrhea that usually lasts a few days, but can last longer in some cases. When gastrointestinal upset and diarrhea last more than two weeks, the condition is known as chronic diarrhea. Some infants with chronic diarrhea either fail to grow, also called FAILURE TO THRIVE, or they begin to lose weight. Excessive loss of water, especially with explosive, frequent episodes of diarrhea, can lead to severe dehydration, especially in small children.
In addition, blood may appear in a child’s stools, which indicates that the infectious germ is causing damage to the lining of the bowel. This is seen more often in certain bacterial infections caused by Campylobacter jejuni, Salmonella, certain strains of
E. coli, and Shigella, in which case the stool may contain mucus as well as blood. One of the most common viral intestinal infections is ROTAVIRUS, which usually causes explosive, watery diarrhea. This is responsible for 35 percent of all hospital admissions in children with gastroenteritis.
Nonbloody diarrhea is usually caused by infections with other bacteria, viruses, or parasites, or by ingesting a toxin produced by bacteria. Many of the viruses, bacteria, and parasites that cause diarrhea also cause other symptoms, such as fever, loss of appetite, abdominal cramps, nausea, vomiting, weight loss, and dehydration.
Occasionally the germs that cause diarrheal infections may spread into the bloodstream, triggering infection in organs far away from the intestines. Salmonella bacteria, for example, can cause infections in the bones (osteomyelitis), joints (arthritis), brain (brain abscess), membranes covering the brain (MENINGITIS). This is especially common in children with chronic illnesses involving the spleen, such as SICKLE-CELL DISEASE.
When to Call a Doctor
A doctor should be consulted when a child has a severe or prolonged episode of diarrhea, fever, vomiting, or severe abdominal pain, or if the stools contain blood or mucus. Especially serious are signs of dehydration, which include dry lips and tongue, pale and dry skin, sunken eyes, listlessness or decreased activity, and decreased urination, such as fewer than six wet diapers a day in an infant.
To determine the speciﬁc germ causing the problem, the doctor may take a sample of a child’s bowel movement for lab tests.
The immediate treatment goal for all diarrheal illnesses is to replace ﬂuids and electrolytes (salt and minerals) that were lost by diarrhea, vomiting, or fever. They can be given by mouth or intravenously, if the child is severely dehydrated. Infants and small children should never be rehydrated with water alone because it does not contain enough sodium, potassium, or other important nutrients.
Depending on the amount of ﬂuid loss and the severity of vomiting and diarrhea, the child may need to eat a milder diet for a day or two, together with special drinks to replace body ﬂuids quickly.
For most diarrheal illnesses caused by bacteria and viruses, antibiotics or antiviral medications are not prescribed because most children recover on their own.
In very young children or in those with weakened immune systems, however, antibiotics are sometimes given to prevent a bacterial infection from spreading throughout the body.
Most parasitic infections are treated with antiparasitic medicines.
Hand-washing is the most effective way to prevent diarrheal infections from passing from child to child. Dirty hands carry infectious germs into the body when a child bites nails or puts any part of the hands into the mouth. Children should wash their hands often, especially after using the toilet and before eating. Clean bathroom surfaces also help to prevent the spread of infectious germs.
Food and water also can carry infectious germs, so fruits and vegetables should be washed thoroughly before eating. Kitchen counters and cooking utensils should be washed thoroughly after they have touched raw meat, especially poultry. Meats should be refrigerated as soon as possible after bringing them home from the supermarket, and they should be cooked until they are no longer pink. After meals, cooked leftovers should be refrigerated as soon as possible.
When traveling, children should never drink from streams, springs, or lakes unless local health authorities have certiﬁed that the water is safe for drinking. Parents also should be careful when buying prepared foods from street vendors, especially if no local health agency oversees the operations.
Pets, especially reptiles, can spread germs if their feeding areas are not separate from family eating areas. Children should never wash pet cages or bowls in the same sink that is used to prepare family meals.