Fever is simply not a great way of deciding whether a child is really sick or not. Children’s bodies can respond to even minor infections with a high fever because their immune systems sense an invader and mount a vigorous response. On the other hand, a child who has say a serious pneumonia may have a lower than normal temperature, because in this case the immune system is overwhelmed and can’t activate all its resources.

The higher the temperature, the greater the metabolism. With the metabolism in overdrive more antibodies and more infection fighting substances can be produced. However, at the same time higher temperature means greater fluid requirements. In other words, children with fever need not only Tylenol or Motrin, but also more fluids such as Pedialyte.

What is more accurate in deciding whether a child is really sick or not is how he or she looks. Is the child alert? Does he or she make good eye contact? Or acting sleepy all the time, with floppy tone. Good appetite argues against a serious infection. So too does playfulness.

If your child is glued to the TV or cellphone game, then it is unlikely that a very critical infection is present. One study found that among children with infections, if a child smiled then there was simply not a single case of serious infection such as pneumonia or meningitis.

This is not to say that no infection exists. Ear infections, strep throats and colds can still occur even if your child looks great. Just remember the next time you are concerned about an infection, rather than focusing on the temperature, step back and ask yourself how your child looks.