(CNN/Parenting) -- Getting the norovirus yourself is awful. Having your kid come down with it? Even worse.
Each year, norovirus leads to about 21 million illnesses, 70,000 hospitalizations and 800 deaths, according to the Centers for Disease Control and Prevention.
The particularly nasty strain of stomach virus that's spreading like wildfire this year, called GII.4 Sydney, can cause violent vomiting, diarrhea and stomach cramps, not to mention "it's messy and stinky and not fun to clean up," says pediatrician and CNN's living well expert Dr. Jennifer Shu.
Here's what to do if your child comes down with the highly contagious bug, which typically lasts two to three days:
"The key is not letting them get dehydrated," says Dr. Gwenn O'Keeffe, CEO of Pediatrics Now and a member of Parenting's advisory board. Check with your child's doctor first, but in general small, frequent sips of liquids containing water, sugar, and electrolytes work best.
For babies, stick with breast milk, formula and an infant/toddler rehydration solution like Pedialyte. For toddlers, offer Pedialyte or water. Older children can sip sports drinks such as Gatorade. Got a reluctant drinker? Try popsicles or Italian ice. Little ones can even suck on ice cubes made with an infant/child rehydration solution, suggests O'Keeffe.
Reintroduce foods carefully
Children may be ready to try solids once they can go progressively longer periods without vomiting liquids, says Shu.
"Avoid creamy or greasy foods; try clear foods such as popsicles and Jell-O, then crackers, bread, pasta, rice, and pretzels," she suggests. O'Keeffe recommends the traditional BRAT diet at this stage -- bananas, rice, applesauce, and toast.
Another option? Cheerios. "They don't put a huge load on the GI system and actually become very mushy in the mouth," says O'Keeffe.
Call the doctor immediately if your child shows signs of dehydration
Those include not keeping down fluids, having no tears when she cries, and infrequent urination. A sunken soft spot is another serious sign of dehydration in an infant (under age 1).
Be especially vigilant about observing very young children. "Babies are unable to communicate when they are feeling sick or thirsty so it's important for parents to look out for signs like being lethargic, having a dry mouth or excessive fussiness," explains Shu. In older kids, also watch for a serious lack of energy. "The earlier intervention is started for dehydration, the better," says O'Keeffe.
Can you avoid norovirus altogether? It's highly contagious, but these prevention strategies are your best bet:
Have kids wash their hands often with soap and water
We're talking really sudsy and for a full 20 to 30 seconds (that's two rounds of "Happy Birthday"). Look for soap with "antibacterial" in the label and make sure kids suds up under their fingernails, advises O'Keeffe.
And don't skip the sink. Hand sanitizers help, but they won't eliminate norovirus completely, says Shu. (If you're on the go, use a sanitizer with at least 60% alcohol to kill other germs until you can get to a sink.)
Break out the bleach
Wipe out norovirus living on surfaces with a bleach-based household cleaner.
"Bleach is the best buster for this virus on surfaces," says O'Keeffe. Clean any surface where the virus may lurk -- especially focus on doorknobs, remote controls and the fridge handle.
Immediately wash clothes, towels or linens that may have come into contact with vomit or stool. (Opt for your washer's longest hot water cycle and then machine-dry them.) Clean your dishes in the dishwasher instead of hand-washing them; the hotter water has a better shot at nuking the bug.
Clean up your cooking
Rinse fruits and veggies before eating them, every time. Be sure to cook all shellfish and produce thoroughly.
Change diapers with care
As if you didn't have enough reasons to dread poopy diapers ... norovirus can be spread through fecal matter, so stock your changing table with bleach-based cleaner and disposable gloves. Always change baby in the same place, ideally on a plastic surface you can clean easily. Post-change, wipe down the surface with bleach and bag the diaper in plastic before tossing it.
Keep them home
Even if your child has stopped throwing up, keep them home from school and activities until they are eating and drinking normally, and they've had no fever for 24 hours, and no puking for at least 48 hours, says O'Keefe.
If you come down with it yourself, you should wait two to three days after your recovery to start preparing food again. The silver lining of this gross bug: you're off kitchen duty!