New parents expect to change lots of messy diapers, but they may not expect that something as common as diarrhea could lead to a trip to the emergency room. In fact, many parents have heard little or nothing about rotavirus-a very common and potentially serious virus-even though nearly all children get infected by age 5.

According to the National Foundation for Infectious Diseases (NFID), rotavirus is responsible for up to 250,000 emergency room (ER) visits and 70,000 hospitalizations in the U.S. every year among kids under 5.

Have you heard of rotavirus?

If you're a parent and have never heard of rotavirus, you're not alone. Holly Robinson Peete, actress and mother of four, had never heard of it when she had to rush her son to the ER because of dehydration caused by rotavirus.

A few years ago, while on a family vacation, Holly's son, then 2 years old, became very ill. He started vomiting profusely and had trouble keeping down liquids. Extremely concerned, Holly and her husband took him to the ER where he was diagnosed with rotavirus diarrhea and received an IV to treat dehydration.

"As the wife of a football player and mother of three boys, I always thought I would have to take one of my sons to the ER for a broken arm or cut, but not for something like diarrhea," says Holly. "It was heart wrenching to see my son so sick, and even scarier, I had never heard of rotavirus before the doctor talked about it. Now it's my turn to get the word out, so others can be aware of rotavirus and the potential effect it can have on a family."

What Can New and Expecting Parents Do About Rotavirus?

There are four important facts about rotavirus that all moms and dads should know:

1. Nearly all children will get rotavirus, the most common cause of severe diarrhea in the U.S., by their fifth birthday

2. Rotavirus is unpredictable. While most children will have a mild case, some can have a severe case. There's no reliable way to tell what kind of experience your child will have.

3. Rotavirus can be serious. By age 5, one in 17 children will visit an emergency room. The virus also accounts for an estimated 70,000 hospitalizations among children under 5 in the U.S. each year.

4. There's something you can do about it. New parents and parents-to-be should talk to their child's doctor about rotavirus and visit NFID.org for more information.

"As a doctor, I have seen many cases of rotavirus and concerned parents of sick children," says Carol J. Baker, M.D., NFID President. "Parents should get the facts on rotavirus before it affects their families."

"My story shows that this can happen to any young child, at any time," adds Holly. "It happened to my child, it can happen to yours."

When her 2-year-old son became seriously ill, actress Holly Robinson Peete learned the dangers of rotavirus. The virus sends thousands of children to the hospital each year.