"I would not want her to make myself worse."
Did you mean to say something else?
Do you mean you are sick and fear to get worse if you do not stay home? Depends on the sickness and the work and the country you live in.
If you are highly contagious, stay home by all means. If you have a chronic illness that makes it hard to attend to the type of work you do, think about different work hours or a different field. If you caught one of the many colds going around all year long and are at the peak with high fever, headaches and anything evil, stay home for a day or so. If it is a lingering cold and you have work deadlines that can not be deferred, go to work and cure yourself on the weekends. That would roughly be the North-American standard.
My girlfriend has a cold. She has been sneezing and coughing with water eyes all day. She is scheduled to work Monday at 9am.
Tell her to take some Day Quil or Aleve cold and sinus medicine, and send her to work. The basic rule is that if you don't have a fever, your probably not contagious.
She has a fever of 102 Degrees. She works at Walmart as a cashier. Handling all of that dirty money.