Cough
When it comes to flu symptoms, nothing is worse than having a bad cough. A persistent severe cough could be a warning signal of flu. Flu viruses can cause cough with wheezing and chest tightness. Unlike the ordinary cold, flu produces a hacking, dry cough. But, in the later stages, you may produce phlegm or mucus while coughing. Flu symptoms including fever tend to go away in around 5 days, but you may still have a cough a few days longer.
