Summarize this article:

This illness affects each area of the gastrointestinal tract. Its symptoms can include nausea and vomiting, diarrhea, abdominal discomfort, and general malaise. Keep in mind that these symptoms can occur from a low grade fever instead, such as one caused by the influenza virus (the "actual flu," unrelated to the stomach flu). The stomach flu is self-limited, meaning the symptoms usually end in 2-3 days, but can last up to 10 days. There is no cure, so focus on preventing it from spreading and making yourself as comfortable as possible while the virus runs its course. The virus is spread by coming in contact with contaminated food, water, utensils, and other objects such as doorknobs that an infected person has touched. Have you come into contact with someone who has the stomach flu? Do you have any of the symptoms of the stomach flu? If your symptoms are mild-moderate nausea, vomiting  and diarrhea, you most likely have a garden variety stomach flu caused by the three most common viral pathogens: norovirus, rotavirus, or adenovirus. In most cases, you do not need medical care to recover from these viruses. This is especially important if your symptoms don't lessen over time. Call a doctor or visit a clinic if you're experiencing the following symptoms:  Increased or constant vomiting for more than a day Fever over 101 °F (38 °C) Diarrhea for more than two days Weight loss Decreased urine production Confusion Weakness If you experience any of the following symptoms, you may have severe dehydration or another serious medical condition. Visit an emergency room or call for emergency services immediately:  Fever higher than 103 °F (39 °C) Confusion Sluggishness (lethargy) Seizures Difficulty breathing Chest or abdominal pains Fainting Blood in vomit or stool No urine in the last 12 hours  Feeling faint or light-headed, especially upon standing A racing pulse Severe or localized abdominal pain (this could indicate appendicitis or pancreatitis) Infants and toddlers are at an increased risk complications such as of dehydration as are diabetics, the elderly or those with HIV. Babies and children are at a higher risk of severe dehydration than adults. If you suspect that your child is suffering from dehydration, seek help immediately.  Some common symptoms include:  No wet diapers for 5 or 6 hours Sunken spot at the top of the skull (fontanel) Dark urine Drier-than-usual mouth and eyes A lack of tears during crying  Skin tenting (if you pinch the skin, it holds the shape) Wash your hands a lot. Prevent the flu from spreading through your household by washing your hands repeatedly. Studies show that you should use regular soap (there is no need for antibacterial soap) and warm water for between 15-30 seconds to wash your hands in order to be highly effective.  Don't touch people if you don't have to.  Avoid unnecessary hugs, kisses, or handshakes. Try not to handle frequently-touched surfaces such as doorknobs, toilet handles, faucet handles, or kitchen cabinet handles. Cover your hand with the sleeve of your shirt, or put a tissue over your hand first. Sneeze or cough into your elbow.  Bend your arm at the elbow and bring it up to your face so that your nose and mouth are in the crook of your arm.  This will prevent germs from getting on your hand, where they're more likely to be spread around. Wash your hands or use hand sanitizer frequently. If you've recently thrown up, sneezed, or handled any other bodily fluid, sanitize your hands. Children should be kept out of school and childcare to prevent the spread of infection. Those affected with Acute gastroenteritis (AGE) are shedding bacteria in their feces for as long as they have diarrhea, so until that stops, they should be kept away from others.  When diarrhea stops the child is free to return to school, as he or she is no longer contagious to others. Your school, however, may require a doctor's note to return, but that is specific to school policy.

Summary:
Understand the symptoms of the stomach flu. Understand how the illness is spread. Assess whether you have a stomach flu. Contact your doctor if your illness is very extreme or persists for a long time. Know when to get emergency care. Be aware that dehydration can be more life-threatening in certain people. Try to avoid infecting others. Keep infected children isolated.