Gastroenteritis

Causes

What causes gastroenteritis in children?

Viruses

Viruses, which account for 30 to 40 percent of gastroenteritis cases in children, can spread quickly through a school or childcare center. Examples include:

• Rotavirus is the leading cause of gastroenteritis in children. A rotavirus is an infection of the stomach and bowel. It spreads when a child who is infected doesn’t wash his or her hands properly after using the toilet and leaves tiny bits of infected stool on surfaces, where they are picked up by another child.

• Norovirus is the leading cause of gastroenteritis in adults; it is a group of viruses that are usually caused by food poisoning. A person can also get norovirus by touching an object or surface that has been infected and then touching the nose, mouth or eyes.

• Adenovirus affects mainly babies and young children. The type of adenovirus that causes diarrhea and respiratory problems spreads through coughs, sneezes or contact with contaminated stool. Stool can spread through contaminated water and poor hand washing (especially after using the bathroom, before eating, or after handling dirty diapers).

Bacteria

Children can get bacterial gastroenteritis from somebody else who has it or from contaminated food.

Examples include:

• Escherichia coli (E. Coli) bacteria are spread through eating undercookedfood or fruits and vegetables that have been washed in contaminated water. E. Coli bacteria can also spread person-to-person by touching unwashed surfaces or animals at farms and petting zoos.

• Shigella bacteria can be found in contaminated food or water, but are most often spread by contact with contaminated stool.

• Salmonella bacteria are a major cause of food poisoning and are frequently found in raw chicken or eggs.

Parasites

Contaminated water and food are common sources of parasitic infection.

Common parasites include:

• Giardia produces symptoms that include diarrhea, low-grade fever, abdominal pains, loss of appetite, nausea and vomiting. Children are more at risk for picking up giardia parasites since they’re more likely to come in contact with feces—for example, if they wear diapers or are toilet training. It is common for infants to pick up giardia at childcare centers and bring it home, causing diarrhea in family members.

• Cryptosporidium causes stomach cramps, fever, nausea and watery diarrhea that can last for two weeks or more. It is common in children who attend day-care centers and children who are exposed to contaminated water (such as by swallowing water in pools, lakes and rivers).

Symptoms

What are the symptoms of gastroenteritis in children?

The symptoms of diarrhea may include:

• Diarrhea
• Fever
• Loss of appetite
• Nausea
• Vomiting
• Abdominal pain

These symptoms may be brief or last for days or weeks, depending on the infection.

Dehydration is a common complication of gastroenteritis. Dehydration is when the body loses too much fluid from vomiting and diarrhea and poor intake.

Some signs of dehydration are:

• Dry mouth or lips
• Fewer or no tears
• Pale skin 
• Irritability or drowsiness
• Fast heart rate
• Dizziness
• Weakness in older children

When to see a doctor

Call the doctor if your child has any of the following:

• Repeated vomiting (can't keep anything down) 
• Has not had anything to drink for more than 12 hours 
• A fever greater than 102° F (greater than 100.4 in an infant less than 3 months old) 
• Severe stomach pain 
• Blood in his or her stool (bowel movement) or in vomit 
• More than 10 liquid or watery stools in 24 hours 
• Diarrhea that lasts longer than one week
• Severe sleepiness or severe irritability 

Go to the emergency room if you have concerns about your child and you cannot reach your child's doctor.

Call 911 or your local emergency number if you are unable to wake your child.