Have you ever heard of rotavirus? Maybe not. Have your children ever had it? Probably so. As the most common cause of diarrhea and dehydration in infants, it affects almost all children before kindergarten age. Globally, rotavirus kills more children than any other disease or accident. In the United States, despite proper health care and clean water, it accounts for 500,000 physician visits, 50,000 hospitalizations and 20 deaths each year.

What is Rotavirus?
Rotavirus is a common virus that causes a form of gastroenteritis in young children. Starting with fever and vomiting, mild to severe diarrhea soon follows, lasting three to nine days. "Rotavirus peaks each year from November to May, beginning in the southwest and spreading to the northeast," says Dr. David Fay, an associate professor of family medicine at George Washington University in Washington D.C. and a family practitioner.

Rotavirus transfers from child to child by touch, living on hard surfaces such as toys or counter tops for short periods. Often a child touches a contaminated surface, touches his mouth and then ingests the germs. "The incubation period for rotavirus is two to four days," says Dr. Fay. Daycare centers and preschool groups pose high risks to young children during the rotavirus season because it's hard to discern when a child is contagious.

Lynn Smith's son began vomiting, but it wasn't until the mom of a child she babysat called that she panicked. "Her son was in the hospital with rotavirus," she says. Smith called the pediatrician immediately, and within two hours her son, too, was hospitalized. "The nurses wouldn't come in without masks, and they put a red container in the room for contaminated trash." Billions of rotavirus particles are passed in the bowel movements of someone who is infected, and hospital staffs take no chances in passing the virus to other patients.

Why Is It So Dangerous?
Diarrhea affects the body's ability to process and absorb necessary water, salts (electrolytes) and nutrition, according to the Center for Disease Control and Prevention (CDC). When a child loses more body fluids and salts than he takes in, he becomes dehydrated.

"Rotavirus can cause significant dehydration, and can be especially dangerous for children less than 2 years old," says Dr. Fay. The younger the child, the more quickly mild dehydration progresses to a dangerous, even life-threatening, level. A young child won't ask for something to drink or eat after a bout of vomiting or diarrhea. She needs to be offered drinks -- often. Signs of dehydration include a decrease in urination, sunken eyes, no tears when crying, unusual drowsiness or fussiness, shriveled skin with no tone and dry, sticky mouth.

The CDC recommends using a rehydration solution such as Ceralyte, Pedialyte or Oralyte rather than sports drinks that do not replace fluid losses correctly. These solutions can be purchased in nearly all drug and grocery stores. Parents of young children should keep two bottles or packages on hand, says the CDC. If your child refuses to drink these, offer Gatorade or its equivalent.

Marla Milling believes her use of Pedialyte kept her son, Ben, out of the hospital when he became ill with rotavirus. "We offered him drinks constantly and found little sips every few minutes helped keep dehydration at bay," she says. Ben, like the vast majority of children with rotavirus, recovered without hospitalization.

What About the Vaccine?
A rotavirus vaccine, approved by the Food and Drug Administration in August 1998, is believed to have caused 23 cases of intussusception (a type of bowel obstruction in which part of the bowel folds in on itself). The vaccine was recalled by July 1999, leaving parents wondering how to protect their children from rotavirus.

"Available data suggests that the risk of intussusception increased during a period of two to three weeks following vaccination," says Dr. Fay. Children immunized before the recall don't seem to be in any danger of intussusception. "However, if any young child develops bloody stools, black stools, abdominal dissention or severe colic pain, parents should contact their doctor regardless of vaccination status."

How Do You Protect Your Child?
When Milling's son, Ben, contracted the illness, his daycare separated him from other children. "I took a printout on rotavirus from the Internet to the daycare staff, and they kept him away from other children while he recovered," she says.

The CDC recommends common sense when it comes to hand washing. Parents should wash their hands after using the toilet, helping a child use the toilet, diapering a child and before preparing, serving or eating food. Children should wash their hands after using the toilet, after having their diapers changed and before eating snacks and meals.

"Hand washing reduces the viral load (the number of living organisms), thus reducing the risk of infection," says Dr. Fay. The virus won't be easily passed with constant hand washing and anti-bacterial soap. Smith's pediatrician told her it's the one thing that can help stop the spread of viruses.

Disinfect toys, bathrooms and food preparation surfaces frequently -- especially if someone in the home is sick. Use diapers with waterproof outer covers that can contain liquid stool or urine, or use plastic pants, says the CDC. Always make sure your children wear clothes over their diapers.

Regardless of your vigilance, your child may still become ill with a nasty bout of diarrhea caused by rotavirus. Don't feel that you've been neglectful. Be secure in your knowledge that, armed with information and common sense, you will be instrumental in helping your child through this unpleasant experience.