The cough triggers vomiting, and because of the respiratory distress and lethargy, the child doesn't want to eat. It's usually contagious three to eight days, but in some cases, up to three weeks. If you think your child may have a respiratory infection, talk to her pediatrician. Colds are believed to be most contagious during the first three days after symptoms appear. The presence of a fever, Dr. Ball said, doesn't always mean a child is contagious, and its absence doesn't mean she's not.
Some colds end in coughs.
A dry, hacking cough that doesn't keep your child up all night is no reason to keep him home from school. But if your child is coughing up green or yellow mucus and still has a fever, keep him home and call your doctor. The flu usually starts with a sudden fever, often accompanied by chills, headache, malaise and cough, which starts off as dry and hacking. Later, sore throat, nasal congestion and cough become more prominent. Also common are abdominal pain, nausea and vomiting.