But communication with your doctor -- or your child's doctor -- should help you make the determination of what you need to do.
"A febrile [feverish] child can't go back to day care or a baby-sitting situation," Pappas said.
Those children usually have to be home for 24 hours, and while parents may be able to find a private baby sitter or work for a place that has care for sick children, those places are few and far between, Pappas said.
"A lot of families don't have extended family nearby," she said.
In that case, the Family and Medical Leave Act may be your only option.
Pappas notes that she has written many notes for parents when they need to stay home to take care of their child.
If the illness is your own and you decide to make the trek into the office, there are a few ways to keep your illness from spreading to your co-workers.
Fryhofer recommends keeping an alcohol-based hand gel with you to eliminate germs, as well as using a tissue when you cough or sneeze.
"Don't shake hands," she added. "If you shake hands with someone, you're going to spread that."
Fryhofer also recommends using phone and e-mail as much as possible, to avoid physical contact with co-workers.
And there is the obvious.
"The most important thing to prevent spreading is, wash your hands. Everyone else in the workplace should wash their hands too," Larson said.
Of course, what happens with your absences is ultimately dependent on your company. But having a sick employee come in isn't ideal for the company either.
"If you're sick, your employer should really not want you at the work place," Fryhofer said.
And some companies are beginning to become aware of that.
Some employers are promoting a virtual work force, using videoconferencing or other technologies to allow employees to work from home when they're sick, according to Cope.
"Employees are encouraged, if they have the ability to work at home, to actually do that," he said. "I think it does make good business sense, if the employee can be accommodated in that fashion."
Ultimately, said Cope, the key is to be in touch with your supervisor or manager of human relations.
"The very first thing I would say is to keep the lines of communication open ... to see what options are available," he said.
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