What Is Viral Gastroenteritis?
Viral gastroenteritis is a common illness that causes abdominal distress. Find out what viral gastroenteritis is, along with symptoms, treatment, and steps to prevent it.
Viral gastroenteritis is the medical term for what many people refer to as “stomach flu.” Whatever you call it, the illness can be absolutely miserable, causing abdominal pain and sending you to the bathroom, frequently and urgently, with diarrhea and vomiting.
If you wonder what viral gastroenteritis is, the answer may be surprising. It turns out “stomach flu” is not any kind of flu at all.
The flu (influenza) is also a viral infection, but it attacks only your respiratory system — your nose, throat, and lungs. The “bug” responsible for the “stomach flu,” on the other hand, is a virus that causes havoc in your gastrointestinal tract, the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) explains.
Most people recover completely from the “stomach flu” after feeling rotten for a week or so, but the virus can have serious complications. That’s why understanding what viral gastroenteritis, and how to treat it and when to call your doctor, is important.
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What causes viral gastroenteritis?
Several different viruses cause the “stomach flu.” All produce similar symptoms, but some symptoms develop a little quicker after you are infected with a certain virus, and some last longer than others.
For example, “stomach flu” caused by adenovirus begins three to 10 days after contact with the virus and lasts for one or two weeks, while rotavirus symptoms begin about two days after you are infected and last from three to eight days. Astrovirus-caused gastroenteritis symptoms typically begin four to five days after infection with the virus and last as little as 24 hours and up to four days.
The primary infectious agent that causes gastroenteritis, however, is norovirus, sickening about 19 to 21 million Americans every year, according to the Centers for Disease Control and Prevention (CDC). Symptoms begin 12 to 48 hours after you become infected with norovirus and last one to three days.
Although rotavirus, adenovirus, and astrovirus most often infect babies and children, norovirus hits people of all ages. Unfortunately, having “stomach flu” doesn’t give you immunity to it in the future, and most people get norovirus repeatedly, about five times during their lifetime, the CDC points out.
“Stomach flu” symptoms and possible complications
The symptoms of virus-caused gastroenteritis include watery diarrhea, abdominal cramps, nausea or vomiting, and sometimes fever. The most common complication of the illness is dehydration, according to the NIDDK.
Be aware of these signs if you, or someone you are caring for, are dehydrated:
- Extreme thirst
- Feeling unusually fatigued
- Not urinating frequently or voiding dark-colored urine
- Eyes and cheeks look sunken
- Feeling light-headed or fainting
- Decreased skin turgor (when skin is pinched and released, not flattening back to normal immediately)
If an infant or young child has viral gastroenteritis, parents and caretakers should watch for these additional warning signs of dehydration: no wet diapers in three hours or more, dry mouth, and no tears when crying.
If your child appears to be dehydrated or is vomiting or has diarrhea, a high fever, or has other medical problems, contact your doctor immediately. Dehydration can be serious in children and, left untreated, can lead to death within a day in babies, according to the NIDDK.
In most cases, gastroenteritis caused by a virus is not dangerous for adults, but it can become life-threatening if it results in severe dehydration, which may require hospitalization. Anyone with signs or symptoms of dehydration that are not relieved with more fluids should see a doctor right away.
It’s especially important for elders, pregnant women, and adults with a weakened immune system or another health condition to seek medical care immediately if they have symptoms of gastroenteritis.
Treatment for viral gastroenteritis
To replace lost fluids and electrolytes to prevent dehydration, or to treat mild dehydration, drink plenty of liquids. Water, fruit juices, sports drinks, and broths are good choices. If you have nausea, try sipping small amounts of clear liquids until you feel better. Older adults and those with weakened immune symptoms or symptoms of dehydration should talk to their doctors about taking oral rehydration solutions.
Over-the-counter medicines such as loperamide (Imodium) and bismuth subsalicylate (Pepto-Bismol, Kaopectate) can help relieve diarrhea. But the NIDDK warns these medicines are not safe for infants and children.
In fact, always talk to your child’s doctor before giving your youngster any over-the-counter medicine. Your child’s pediatrician can give advice on oral rehydration solutions such as Pedialyte you can use to help rehydrate youngsters with gastroenteritis. You should give infants breast milk or formula as usual.
How to prevent viral gastroenteritis
You can’t always avoid the germs that cause viral gastroenteritis, but these tips from the CDC can help prevent the spread of the disease:
- Wash your hands thoroughly and often. Wash with soap and water, especially after using the toilet or changing diapers. Always wash your hands well before preparing food or eating, too.
- Handle and prepare food safely. Carefully wash fruits and vegetables. Oysters and other shellfish are sometimes contaminated with norovirus. Make sure they are cooked thoroughly before eating.
- If you are sick, don’t prepare food for others. Wait at least two days after symptoms go away before you prepare, cook, and serve food.
- Clean and disinfect surfaces. After you vomit or have diarrhea, use a bleach-based household cleaner or a solution made with five tablespoons to 1.5 cups of household bleach per gallon of water to disinfect the area.
- Wash laundry thoroughly. Immediately remove and wash clothing or sheets that may have vomit or other bodily fluids on them. Wear disposable gloves if possible, to handle soiled items, then wash your hands afterwards. Wash soiled items with detergent and hot water at the maximum available cycle length, and dry them on the hottest heat setting.
Updated:  
February 01, 2022
Reviewed By:  
Janet O’Dell, RN