Brief Answer: You should take him to a clinic... Detailed Answer: Hi, thank you for posting. If in your son's school there are cases with whooping cough, you shouldn't allow your son to go in school for a few days. In general the main symptom of pertussis(whooping cough) is cough that lasts for a few weeks, that is loud and in bark form, followed by difficulty in breathing. (This symptom will show up if you son is not vaccinated). If your son is vaccinated the symptoms are light. However you should take him to a clinic and contact an infectologist. For any doubts ask me. Dr. Behar.