What is Viral Gastroenteritis?
Viral gastroenteritis is an intestinal infection caused by several different viruses. Highly contagious, viral gastroenteritis is the second most common illness in the United States. It causes millions of cases of diarrhea each year.
Anyone can get viral gastroenteritis and most people recover without any complications. However, viral gastroenteritis can be serious when people cannot drink enough fluids to replace what is lost through vomiting and diarrhea — especially infants, young children, the elderly, and people with weak immune systems.
What Are The Symptoms of Viral Gastroenteritis?
The main symptoms of viral gastroenteritis are watery diarrhea and vomiting. Other symptoms are headache, fever, chills, and abdominal pain. Symptoms usually appear within 4 to 48 hours after exposure to the virus and last for 1 to 2 days, though symptoms can last as long as 10 days.
What Are The Causes?
The viruses that cause viral gastroenteritis damage the cells in the lining of the small intestine. As a result, fluids leak from the cells into the intestine and produce watery diarrhea. Four types of viruses cause most viral gastroenteritis.
- Rotavirus is the leading cause among children 3 to 15 months old and the most common cause of diarrhea in children under the age of 5 years. Symptoms of rotavirus infection appear 1 to 2 days after exposure. Rotavirus typically causes vomiting and watery diarrhea for 3 to 8 days, along with fever and abdominal pain. Rotavirus can also infect adults who are in close contact with infected children, but the symptoms in adults are milder. In the United States, rotavirus infections are most common from November to April.
- Adenovirus occurs mainly in children under the age of 2 years. Of the 49 types of adenoviruses, one strain affects the gastrointestinal tract causing vomiting and diarrhea. Symptoms typically appear 1 week after exposure. Adenovirus infections occur year round.
- Caliciviruses cause infection in people of all ages. This family of viruses is divided into 4 types, the noroviruses being the most common and most responsible for infecting people. The noroviruses are usually responsible for epidemics of viral gastroenteritis and occur more frequently from October to April. Infected people experience vomiting and diarrhea, fatigue, headache, and sometimes muscle aches. The symptoms appear within 1 to 3 days of exposure.
- Astrovirus also infects primarily infants, young children, and the elderly. This virus is most active during the winter months. Vomiting and diarrhea appear within 1 to 3 days of exposure.
Viral gastroenteritis is often mistakenly called “stomach flu,” but it is not caused by the influenza virus and it does not infect the stomach. Also, viral gastroenteritis is not caused by bacteria or parasites. For information about bacterial infections, please see the Bacteria and Foodborne Illness fact sheet from the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK).
Viral gastroenteritis is highly contagious. The viruses are commonly transmitted by people with unwashed hands. People can get the viruses through close contact with infected individuals by sharing their food, drink, or eating utensils, or by eating food or drinking beverages that are contaminated with the virus. Noroviruses in particular, are typically spread to other people by contact with stool or vomit of infected people and through contaminated water or food — especially oysters from contaminated waters.
People who no longer have symptoms may still be contagious, since the virus can be found in their stool for up to 2 weeks after they recover from their illness. Also, people can become infected without having symptoms and they can still spread the infection.
Outbreaks of viral gastroenteritis can occur in households, child care settings, schools, nursing homes, cruise ships, camps, dormitories, restaurants, and other places where people gather in groups. If you suspect that you were exposed to a virus in one of these settings or by foods prepared on the premise of places such as a restaurant, deli, or bakery, you may want to contact your local health department, which tracks outbreaks.
If you think you have viral gastroenteritis, you may want to see your doctor. Doctors generally diagnose viral gastroenteritis based on the symptoms and a physical examination. Your doctor may ask for a stool sample to test for rotavirus or to rule out bacteria or parasites as the cause of your symptoms. No routine tests are currently available for the other types of viruses.
Most cases of viral gastroenteritis resolve over time without specific treatment. Antibiotics are not effective against viral infections. The primary goal of treatment is to reduce the symptoms, and prompt treatment may be needed to prevent dehydration.
Your body needs fluids to function. Dehydration is the loss of fluids from the body. Important salts or minerals, known as electrolytes, can also be lost with the fluids. Dehydration can be caused by diarrhea, vomiting, excessive urination, excessive sweating, or by not drinking enough fluids because of nausea, difficulty swallowing, or loss of appetite.
In viral gastroenteritis, the combination of diarrhea and vomiting can cause dehydration. The symptoms of dehydration are:
- excessive thirst
- dry mouth
- little or no urine or dark yellow urine
- decreased tears
- severe weakness or lethargy
- dizziness or lightheadedness
If you notice any of these symptoms, you should talk to your doctor. Mild dehydration can be treated by drinking liquids. Severe dehydration may require intravenous fluids and hospitalization. Untreated severe dehydration can be life threatening.
Children present special concerns. Because of their smaller body size, infants and children are at greater risk of dehydration from diarrhea and vomiting. Oral rehydration solutions such as Pedialyte can replace lost fluids, minerals, and salts.
The following steps may help relieve the symptoms of viral gastroenteritis:
- Allow your gastrointestinal tract to settle by not eating for a few hours.
- Sip small amounts of clear liquids or suck on ice chips if vomiting is still a problem.
- Give infants and children oral rehydration solutions to replace fluids and lost electrolytes.
- Gradually reintroduce food, starting with bland, easy-to-digest food, like toast, broth, apples, bananas, and rice.
- Avoid dairy products, caffeine, and alcohol until recovery is complete.
- Get plenty of rest.
Prevention is the best way to avoid viral gastroenteritis by following the tips listed below. No vaccine is available for viral gastroenteritis with the exception of a newly released rotavirus vaccine called Rotateq. The oral vaccine for infants aged 6 to 32 weeks was approved in February 2006 by the U.S. Food and Drug Administration. Otherwise, you can avoid infection by:
- washing your hands thoroughly for 20 seconds after using the bathroom or changing diapers
- washing your hands thoroughly for 20 seconds before eating
- disinfecting contaminated surfaces such as counter tops and baby changing stations
- not eating or drinking foods or liquids that might be contaminated
Points to Remember
- Viral gastroenteritis is a highly contagious infection of the intestines caused by one of several viruses.
- Although sometimes called “stomach flu,” viral gastroenteritis is not caused by the influenza virus and does not affect the stomach.
- The main symptoms are watery diarrhea and vomiting.
- Anyone can get viral gastroenteritis through unwashed hands, close contact with an infected person, or food and beverages that contain the virus.
- Diagnosis is based on the symptoms and a physical examination. Currently only rotavirus can be rapidly detected in a stool test.
- Viral gastroenteritis has no specific treatment; antibiotics are not effective against viruses. Treatment focuses on reducing the symptoms and preventing dehydration.
- The symptoms of dehydration are excessive thirst, dry mouth, dark yellow urine or little or no urine, decreased tears, severe weakness or lethargy, and dizziness or lightheadedness.
- Infants, young children, the elderly, and people with weak immune systems have a higher risk of developing dehydration due to vomiting and diarrhea.
- People with viral gastroenteritis should rest, drink clear liquids, and eat easy-to-digest foods.
- For infants and young children, oral rehydration solutions can replace lost fluids, minerals, and salts.
- Avoid viral gastroenteritis by washing hands thoroughly after using the bathroom or changing diapers, disinfecting contaminated surfaces, and avoiding foods or liquids that might be contaminated.
The following information comes from The National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), a part of the National Institutes of Health (NIH) and the U.S. Department of Health and Human Services. To ensure that you’re viewing the most up-to-date information, we recommend visiting the viral gastroenteritis entry at the NIDDK website.
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Orlando Patients, Find Help for Your Gastroparesis
Gastroparesis is also called delayed gastric emptying. It is a disorder in which the stomach takes too long to empty. Usually, the stomach contracts to move food down into the small intestine for digestion. In a person with gastroparesis, the muscles of the stomach and intestines do not work normally, and food moves slowly or stops moving through the digestive tract.
What Causes Gastroparesis?
The most common cause of gastroparesis is diabetes. People with diabetes have high blood glucose, which, over time, can damage the vagus nerve that controls food movement through the digestive tract.
Other causes of gastroparesis include:
- surgery on the stomach or vagus nerve
- viral infections
- anorexia nervosa or bulimia
- medications that slow contractions in the intestine
- gastroesophageal reflux disease
- smooth muscle disorders, such as amyloidosis and scleroderma
- nervous system diseases, including abdominal migraine and Parkinson’s disease
- metabolic disorders, including hypothyroidism
Many people have what is called idiopathic gastroparesis, meaning the cause is unknown and cannot be found even after medical tests.
What Are The Symptoms of Gastroparesis?
Signs and symptoms of gastroparesis include:
- pain in the upper abdomen
- vomiting of undigested food, sometimes several hours after a meal
- early feeling of fullness after only a few bites of food
- weight loss due to poor absorption of nutrients or low-calorie intake
- abdominal bloating
- high and low blood glucose levels
- lack of appetite
- gastroesophageal reflux
- spasms in the stomach area
Eating solid foods, high-fiber foods such as raw fruits and vegetables, fatty foods, or drinks high in fat or carbonation may contribute to these symptoms.
How is Gastroparesis Diagnosed?
After performing a full physical exam and taking your medical history, your Orlando Gastroenterology doctor may order several blood tests to check blood counts and chemical and electrolyte levels.
To rule out an obstruction or other conditions, the doctor may perform an upper endoscopy, ultrasound, or barium x-ray. Once other causes have been ruled out, the doctor will perform a gastric emptying test to confirm a diagnosis of gastroparesis.
How is Gastroparesis Treated?
Treatment of gastroparesis depends on the severity of the symptoms. In most cases, gastroparesis is chronic, so the best strategy is management of symptoms.
Several medications are used to treat gastroparesis. Doctors at Orlando Gastroenterology may try different drugs or combinations to find the most effective treatment.
Changing eating habits can help control gastroparesis. A doctor or dietitian may prescribe six small meals a day instead of three large ones. If less food enters the stomach at mealtimes, it may not become overly full. In more severe cases, a liquid or pureed diet may be prescribed.
The doctor may recommend avoiding high-fat and high-fiber foods. Fat naturally slows digestion, and fiber is difficult to digest. Some high-fiber foods like oranges and broccoli contain material that cannot be digested.
If a liquid or pureed diet does not work, surgery may be needed to insert a feeding tube that will deliver nutrients and medication into the small intestine. These products then get into the bloodstream quickly. This procedure, called a jejunostomy, is used only when gastroparesis is severe.
The above information comes from The National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), a part of the National Institutes of Health (NIH) and the U.S. Department of Health and Human Services. To ensure that you’re viewing the most up-to-date information, we recommend visiting the bleeding in the digestive tract entry at the NIDDK website.