No one likes to be sick. As a parent, when you feel terrible, you just wish that the world would stop and you could just curl up on your bed and sleep. Unfortunately, this is not how the world works. Even when you are sick there are things that have to be done.

However, when your kids are sick, you'll need to decide whether they are contagious or not before sending them off on their way. You don't want to spread whatever your child has to the entire school.

So how do you know when your child is contagious?

1. Fever

Fever is a sign that your body is still fighting the virus or bacteria. A fever is always a sign of sickness, so if you notice that your child's temperature is running high, it's a sign they should stay home today.

2. Runny nose

If their sinuses are draining, they are sick - despite the color of the drainage. "All colds are contagious regardless of mucus color." says Sara DuMond, MD.

3. Feeling sick

We live in a culture where even if you are feeling sick, you just keep going. When our kids say they feel sick, it can be easy to ignore it and send them on their way.

However, that might not be the best approach. DuMond said, "When your child is feeling his worst (days three through five), he's most contagious. But symptoms can last for up to two weeks, and he's contagious as long as he's sick. Of course, you can't quarantine him for days. So wash your hands frequently after touching him, and keep him away from other kids during the ... peak."

"In most of us, flu is contagious for about a week. By the time you're feeling better, you have probably stopped spewing virus particles everywhere," Dr. Salber says. Therefore, if you are feeling really sick you are probably still contagious.

When should you keep the kids home?

If you suspect your child is contagious you should keep your kids home - it might be inconveinent, it might be unexpected, but it's the right thing to do.

What to do?

If your child is sick there are a lot of options. You can see if you can work from home, take a sick day yourself or call the grandparents or a trusted neighbor to keep an eye on your child. Be sure to call the school and excuse your child's absence and work on getting their day's work so they don't fall behind.