Step-by-step explanation:
Influenza (flu) can cause mild to severe illness, and at times can lead to death. Flu is different from a cold. Flu usually comes on suddenly.Flu is a contagious respiratory illness caused by influenza viruses that infect the nose, throat, and sometimes the lungs. It can cause mild to severe illness, and at times can lead to death. The best way to prevent flu is by getting a flu vaccine each year.
 all of these symptoms:
fever* or feeling feverish/chills 
cough 
sore throat 
runny or stuffy nose 
muscle or body aches 
headaches 
fatigue (tiredness) 
some people may have vomiting and diarrhea, though this is more common in children than adults.