Third day of school and our house already sounds like an influenza ward. Naturally, our kids are going to school anyway.
Here in Spain, the concept of keeping your kids at home when they are sick (but not actually in mortal danger) is not really understood. The fact that other children might also get sick doesn't seem to bother anyone.
A flowchart to illustrate the typical thought process of a Spanish parent:
For that matter, people think that we are weird when we say we'd rather not kiss hello because we are sick and don't want to infect anyone.