What to Know About Viral Gastroenteritis (Stomach Flu)

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    Viral gastroenteritis can cause nausea and vomiting. You can get the virus that causes it from other people or through contaminated foods, drinks, or surfaces. Washing your hands often may help prevent it.

    Viral gastroenteritis is an inflammation and irritation of your intestines caused by one of a number of viruses, most commonly norovirus or rotavirus. This illness is also known as the stomach flu.

    This highly contagious illness spreads through close contact with people who have the virus or through contaminated food or water.

    It can easily spread in close quarters, such as:

  • childcare facilities
  • schools
  • nursing homes
  • cruise ships
  • This article will help you understand more about viral gastroenteritis including symptoms, causes, treatment, and prevention.

    What are the symptoms of viral gastroenteritis?

    Symptoms of gastroenteritis usually begin shortly after infection. For example, symptoms caused by norovirus typically develop within 12 to 48 hours. Symptoms from adenoviruses may be delayed 3 to 10 days after contact.

    Depending on which type of virus you’ve contracted, symptoms can last anywhere from 1 to 14 days. Symptoms often start suddenly over the course of 1 or 2 hours.

    Symptoms can include:

  • loose, watery diarrhea more than 3 times per day
  • fever or chills
  • nausea and vomiting
  • headache, muscle aches, or joint aches
  • sweating or clammy skin
  • abdominal cramps and pain
  • loss of appetite
  • Diarrhea caused by viral gastroenteritis isn’t usually bloody. Blood in your stool could be a sign of a more severe infection.

    You should seek emergency medical treatment if:

  • diarrhea has lasted for 2 days or more without getting less frequent
  • your infant develops diarrhea
  • blood is present in your diarrhea
  • you show or see signs of dehydration, such as dry lips or dizziness
  • In addition to the above symptoms, you should seek emergency attention for your child if they have the appearance of sunken eyes or if they aren’t making tears when they cry.

    What causes viral gastroenteritis?

    Viral gastroenteritis is caused by a number of different viruses. It’s easy for these viruses to spread in group situations. Some of the ways the virus is transmitted include:

  • eating contaminated food or drinking contaminated water
  • being in close contact with someone who has the virus
  • sharing utensils or other items with someone who has the virus
  • touching contaminated surfaces
  • not washing hands properly, especially food handlers
  • Viral gastroenteritis affects people of all ages all over the world. But some factors can increase the risk of contracting viral gastroenteritis. People who are at a higher risk include:

  • children under the age of 5
  • older adults, especially those who live in nursing homes or assisted living facilities
  • people with a compromised or weakened immune system
  • those who are often in group settings, such as schools, dormitories, day care, religious gatherings, and other indoor group settings
  • Other factors that may increase the risk of becoming ill with viral gastroenteritis include:

  • being malnourished, especially low levels of vitamin A or zinc
  • recent travel to developing countries
  • antibiotic or antacid use
  • anal intercourse
  • Several different types of viruses can cause viral gastroenteritis. The most common include:

  • norovirus
  • rotavirus
  • adenovirus
  • astrovirus
  • Let’s look at each of these viruses in more detail.

    Norovirus

    Norovirus is highly contagious and can affect anyone at any age. It spreads through contaminated food, water, and surfaces, or by people who have the virus. Norovirus is common in crowded spaces.

    Norovirus is the leading cause of gastroenteritis in the United States and worldwide. Most outbreaks in the United States occur between November and April.

    Symptoms include:

  • nausea
  • diarrhea
  • fever
  • body aches
  • According to the Centers for Disease Control and Prevention (CDC), most people who become ill with norovirus start to feel better within 1 to 3 days of symptom onset.

    Rotavirus

    Rotavirus commonly affects infants and young children. Those who contract it can then pass the virus to other children and adults. It’s usually contracted and transmitted via the mouth.

    Symptoms typically appear within 2 days of infection and include:

  • vomiting
  • loss of appetite
  • watery diarrhea that lasts anywhere from 3 to 8 days
  • A rotavirus vaccine was approved for infants in 2006. Early vaccination is recommended to prevent severe rotavirus illnesses in infants and small children.

    Adenovirus

    The adenovirus affects people of all ages. It can cause several types of illness, including gastroenteritis. The adenovirus can also cause common cold-like symptoms, bronchitis, pneumonia, and pink eye (conjunctivitis).

    Children in daycare, especially those under 2 years of age, are more likely to get adenovirus.

    Adenovirus is passed through the air via sneezing and coughing, by touching contaminated objects, or by touching the hands of someone with the virus.

    Symptoms associated with adenovirus include:

  • sore throat
  • pink eye
  • fever
  • coughing
  • runny nose
  • Most children will feel better within a few days of experiencing adenovirus symptoms. However, symptoms such as pink eye may last longer than a few days.

    Astrovirus

    Astrovirus is another virus that commonly causes gastroenteritis in children. Symptoms associated with astrovirus include:

  • diarrhea
  • headache
  • mild dehydration
  • stomach pain
  • The virus most often affects people in late winter and early spring. It’s transmitted through contact with a person who has the virus or via an infected surface or food.

    Symptoms usually appear within 2 to 3 days after initial exposure, and the virus will usually go away within 1 to 4 days.

    What are the complications of viral gastroenteritis?

    The main complication of viral gastroenteritis is dehydration, which can be quite severe in babies and young children. Viral gastroenteritis accounts for over 200,000 childhood deaths worldwide per year.

    Other complications of viral gastroenteritis include:

  • nutritional imbalances
  • body weakness or fatigue
  • muscle weakness
  • Dehydration can be life threatening. Call your doctor if you or your child have these symptoms:

  • diarrhea lasting more than a few days
  • blood in the stool
  • confusion or lethargy
  • dizziness or feeling like you’re going to faint
  • nausea
  • dry mouth
  • an inability to produce tears
  • no urine for more than 8 hours or urine that is dark yellow or brown
  • sunken eyes
  • sunken fontanel on an infant’s head
  • Dehydration that accompanies viral gastroenteritis can lead to several complications of its own. These include:

  • brain swelling
  • coma
  • hypovolemic shock, a condition that occurs when your body doesn’t have enough fluid or blood
  • kidney failure
  • seizures
  • To prevent complications, get immediate medical attention if you or your child have symptoms of dehydration.

    How is viral gastroenteritis treated?

    Most of the time, your medical history and physical exam are the basis for diagnosis, especially if there’s evidence that the virus is spreading through your community.

    Your doctor may also order a stool sample to test for the type of virus, or to find out if your illness is caused by a parasitic or bacterial infection.

    The main focus of treatment is to prevent dehydration by drinking plenty of fluids. In severe cases, hospitalization and intravenous fluids may be necessary.

    Over-the-counter oral rehydration solutions (OHS), such as Pedialyte, can be helpful in mild cases. These solutions are easy on your child’s stomach, and contain a balanced mixture of water and salts to replenish essential fluids and electrolytes.

    These solutions are available at local pharmacies and don’t require a prescription. However, you should follow the instructions carefully.

    Antibiotics have no effect on viruses. Check with your physician before taking any over-the-counter medications.

    Shop online for oral rehydration solutions such as Pedialyte and oral electrolyte products.

    Treating diarrhea and vomiting

    Diarrhea can be treated in adults with over-the-counter medications such as loperamide (Imodium) or bismuth subsalicylate (Pepto-Bismol).

    Your doctor may also prescribe probiotics to replace the healthy bacteria that’s lost during diarrhea or they may prescribe medications to treat severe vomiting.

    What to eat and what to avoid

    As you start to feel better and reintroduce foods into your diet, it’s best to opt for bland foods, such as:

  • rice
  • potatoes
  • toast
  • bananas
  • applesauce
  • These foods are easier to digest and less likely to cause further stomach upset. Until you’re feeling better, you may want to avoid some types of foods, such as:

  • fatty or fried foods
  • caffeine
  • alcohol
  • sugary foods
  • dairy products
  • Self-care steps

    If you have viral gastroenteritis, consider these self-care measures to help ease your symptoms and prevent dehydration:

  • Drink extra fluids with and between meals. If you have difficulty, try drinking very small amounts of water or sucking on ice chips.
  • Avoid fruit juices. These don’t replace the minerals that you’ve lost and can actually increase diarrhea.
  • Electrolytes. Children and adults can consume sports drinks to replenish electrolytes. Younger children and infants should use products formulated for children, such as OHS.
  • Limit portion sizes. Try to eat food in smaller amounts to help your stomach recover.
  • Get lots of rest. Prioritize getting at least 7 to 8 hours of sleep each night. Don’t exert yourself until you feel that you have your usual level of energy and strength.
  • Medications. Check with your doctor before taking medications or giving them to children. Never give aspirin to children or teenagers with a viral illness. This can cause Reye’s syndrome, a potentially life threatening condition.
  • What home remedies help if you have viral gastroenteritis?

    In addition to rehydrating and resting, there are some natural and home remedies that may help you relieve the symptoms of viral gastroenteritis.

    Heating pad or heat pack

    If you have abdominal pain, try applying a low-temperature heating pad or a warm heat pack to your stomach. Cover the heating pad with a cloth and don’t leave it on for more than 15 minutes at a time.

    The heat can help relax the muscles in your digestive tract and keep them from spasming.

    Shop online for heating pads and heat packs.

    Brown rice water

    Some parents serve rice water to their children. This is the water that remains after boiling brown rice. It’s high in electrolytes and can help with rehydration.

    To make rice water:

  • Boil 1 cup of rice and 2 cups of water for about 10 minutes until the water becomes cloudy.
  • Strain the rice and keep the water.
  • Cool the rice water before serving.
  • Ginger

    Products containing ginger, such as ginger ale or ginger tea, may help soothe an upset stomach.

    A 2019 review of studies found that a divided daily dose of 1,500 milligrams of ginger taken in two parts throughout the day may help reduce nausea. More research needs to be done on ginger’s ability to treat other gastrointestinal symptoms.

    Shop online for ginger ale and ginger tea.

    Mint

    Mint may also have anti-nausea properties similar to those of ginger. Sipping a soothing mint tea may help you feel better.

    Studies have found that peppermint oil may help relax the muscles in your gut. It also has anti-microbial and anti-inflammatory properties.

    Shop online for mint tea.

    Yogurt or kefir

    Although dairy products should be avoided when you have your most acute symptoms, eating unflavored yogurt with live active cultures or drinking kefir may help restore your body’s natural bacterial balance after illness.

    Shop online for plain yogurt and kefir.

    How can you prevent viral gastroenteritis?

    Viral gastroenteritis can spread easily. However, there are some steps you can take to lower your risk of contracting the virus or passing it to others.

    Prevention tips

  • Wash your hands often, especially after using the bathroom and before food preparation. If necessary, use hand sanitizer until you can access soap and water.
  • Don’t share kitchen utensils, plates, or towels if someone in your household is sick.
  • Don’t eat raw or undercooked foods.
  • Wash fruits and vegetables thoroughly.
  • Take special precautions to avoid contaminated water and food when traveling. Avoid ice cubes and use bottled water whenever possible.
  • Ask your doctor if you should have your infant vaccinated against rotavirus. There are two vaccines, and they’re generally started around 2 months old.
  • The takeaway

    Viral gastroenteritis is an inflammation and irritation of your intestines caused by one of several types of viruses.

    Vomiting and diarrhea are among the most common symptoms. You can get viral gastroenteritis from other people or through contaminated foods, drinks, or surfaces.

    Generally, viral gastroenteritis symptoms come on suddenly and pass quickly. If diarrhea lasts longer than 48 hours, be sure to follow up with your doctor.

    It’s also a good idea to get medical attention if your infant or young child develops diarrhea because it can lead to serious complications due to dehydration.

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