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Stomach Flu: How to Identify and Treat Viral Gastroenteritis

Viral gastroenteritis, often called the stomach flu or stomach bug, is an illness that can cause a lot of unpleasant symptoms, such as vomiting or diarrhea. Read on to learn more about the symptoms and treatment options for the stomach flu, plus ways to prevent it.

Stomach flu is a very common illness. Despite its name, it’s not related to the seasonal flu or influenza. Stomach flu actually refers to viral gastroenteritis, an infection of the digestive tract.

You’ve likely had the stomach flu in the past as this illness is very common. In fact, it’s the second-most common illness in the United States, after the common cold. 

When people talk about the stomach flu, they’re referring to viral gastroenteritis. This is an infection of your stomach and intestine, and it causes diarrhea and other gastrointestinal symptoms. In contrast, the seasonal flu affects your respiratory system, such as your nose and lungs.

Stomach flu can be caused by many different viruses. Often, norovirus or rotavirus are responsible, but other viruses can cause the stomach flu. If you come in contact with one of these viruses, you could get sick. 

Both children and adults are affected by norovirus, the most common cause of foodborne illness worldwide. In children, rotavirus is the most common cause of viral gastroenteritis. Many other viruses, such as astrovirus and adenovirus, can cause the stomach flu, too. 

Stomach flu is very contagious and can sweep through crowded places, such as hospitals, schools, and cruise ships. You don’t need to be exposed to many virus particles to get sick. In the case of norovirus, it takes less than 100 virus particles. There are many ways you could pick up these germs, including:

  • Eating food that was prepared by an infected person
  • Sharing utensils or towels with an infected person
  • Touching an infected person, such as when you’re caring for them
  • Touching contaminated surfaces, such as doorknobs or countertops
  • Drinking water that’s been contaminated by sewage
  • Eating raw or undercooked oysters

How long does a stomach virus last? Fortunately, it’s typically a short-lived illness. However, some people experience lingering symptoms even after the infection is resolved.

While the stomach flu can cause some very uncomfortable gastrointestinal symptoms, these symptoms don’t usually hang around for long. Most people only have symptoms for a day or two. Sometimes, the stomach flu can last for up to 10 days. 

In the weeks or months after the infection goes away, some people notice lingering gastrointestinal symptoms. This is called post-infectious irritable bowel syndrome. The cause of this condition isn’t known, but one theory is that the stomach flu alters your normal bowel bacteria. The good news is that post-infectious irritable bowel syndrome tends to get better over time.

Stomach bug symptoms typically start soon after you’re exposed to the stomach virus. Unlike the seasonal flu, the stomach flu doesn’t cause respiratory symptoms. It can cause many unpleasant gastrointestinal symptoms, such as diarrhea or vomiting.

If you’re exposed to the stomach virus, you may start feeling ill fairly quickly. Depending on the type of virus, you could start feeling sick one to three days after the infection. Norovirus can make you sick in as little as 12 hours.

The stomach flu’s symptoms are much different from those of the seasonal flu. People with seasonal flu often have runny or stuffy noses, sore throats, and coughs. These aren’t symptoms of the stomach flu.

Stomach bug symptoms typically start soon after you’re exposed to the stomach virus. Unlike the seasonal flu, the stomach flu doesn’t cause respiratory symptoms.

The most common stomach virus symptoms include nausea, vomiting, and diarrhea. The latter two may occur many times a day, which can leave you feeling very sick. When you have the stomach flu, your diarrhea is watery and usually not bloody. Bloody diarrhea is usually associated with more serious infections. 

Stomach flu can cause other symptoms, too. If you have the stomach flu, you could also have a stomach ache or abdominal cramps. A stomach bug may cause a low-grade fever or chills. Some people experience occasional muscle aches or even headaches.

Some people with the stomach flu could experience a potentially serious complication: dehydration. You can become dehydrated if you don’t replace the liquids you lose from frequent vomiting and diarrhea. Some symptoms of dehydration include a dry mouth, excessive thirst, and dark yellow urine. 

Treatment for the stomach flu is generally limited to home remedies. There are few treatments that doctors can offer, and antibiotics don’t help. People who experience symptoms or complications need to see a doctor. Your doctor may recommend appropriate tests or treatments. 

Stomach flu is usually self-limiting, which means that it goes away on its own. Many home remedies and self-care measures can help you feel more comfortable while you wait for the stomach flu to go away. 

To prevent dehydration, make sure you drink enough fluids. This can be difficult when you don’t feel well, but try taking small, frequent sips of liquids. Water and clear broths are good choices. Sucking on ice chips is another option. Stay away from drinks that contain alcohol or caffeine. 

While you’re recovering, stay home from work or school to avoid passing the virus to other people. Try to get plenty of rest while you’re home.

If you feel nauseous, avoid food for a few hours to help your stomach settle. When you start feeling hungry again, try eating bland foods that are easy on your stomach. Some examples include crackers, bananas, gelatin, and toast. If you start feeling nauseous again, stop eating and try again later.

While you’re recovering, stay home from work or school to avoid passing the virus to other people. Try to get plenty of rest while you’re home. This can help with fatigue, in addition to helping you recover. Your body needs sleep to fight off the stomach flu virus, so if you don’t get enough sleep, it could take longer for you to recover. 

Stomach flu usually goes away by itself, but some people may require medical attention. See your doctor if you have severe symptoms, such as bloody diarrhea, signs of dehydration, or a fever over 104 degrees Fahrenheit.

To diagnose your illness, your doctor may ask questions about your symptoms and perform a physical exam. Sometimes, they may ask you to submit a stool sample. A rapid stool test can quickly determine if norovirus or rotavirus, two common causes of the stomach flu, are present. But there are no quick tests for other viruses that cause gastroenteritis. Your doctor may ask you to submit a stool sample to identify a possible bacterial or parasitic infection.

There are few treatments that doctors can offer for the stomach flu. People who are very dehydrated may need to receive intravenous fluids. You may want your doctor to prescribe antibiotics, but these drugs won’t help you feel better. That’s because antibiotics kill bacteria, not viruses. Taking antibiotics when they’re not necessary can contribute to antibiotic resistance. 

Since there’s no effective treatment for viral gastroenteritis, prevention is the best strategy. Washing your hands regularly can help you stay healthy. For children, there’s a vaccine that may help prevent the stomach flu. There is no vaccine for adults.

Handwashing can help you prevent the spread of viruses that cause the stomach flu. Wash your hands after going to the bathroom, after changing a diaper, and before preparing food. Thoroughly washing your hands should take at least 20 seconds, so don’t rush. Make sure you wash under your fingernails and around your cuticles. If you can’t wash your hands, use hand sanitizer and sanitizing wipes.

If possible, stay away from people who are infected with the stomach flu. If members of your own household are sick, separate their laundry to avoid spreading germs. Avoid sharing cups, utensils, and towels.

Since there’s no effective treatment for viral gastroenteritis, prevention is the best strategy. Washing your hands regularly can help you stay healthy.

When norovirus gets on a hard surface, such as a doorknob or faucet, it can remain infectious for weeks. If someone in your household is sick, it’s a good idea to clean these surfaces. Not all disinfectants kill norovirus, but you can create an effective disinfectant by adding 2 cups of bleach to 1 gallon of water. 

A rotavirus vaccine is available for children. Two brands of the rotavirus vaccine are available in the United States, and both are given in the form of mouth drops. Starting at 2 months old, infants should get two or three doses depending on the brand of rotavirus vaccine. Clinical trials have shown that the rotavirus vaccine is very effective. 

There’s no vaccine for norovirus, the most common cause of the stomach flu in adults. It’s difficult to create a vaccine because there are multiple strains of norovirus and the virus can mutate. You may wonder if the flu shot can provide some protection from the stomach flu. Unfortunately, the flu shot only protects against the viruses that cause seasonal flu, not the viruses that cause the stomach flu.

Stomach flu is an intestinal infection that can cause a number of symptoms, including vomiting and watery diarrhea. This infection usually goes away by itself fairly quickly, but home remedies can help keep you comfortable while your immune system fights it off.
















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