The flu (influenza) is an illness caused by flu viruses that infect the nose, throat, and lungs.  Anyone can get the flu. Symptoms range in severity and can include fever, cough, fatigue, headache, and a runny or stuffy nose. The flu can also cause vomiting and diarrhea, though this is more common in children than adults. Most people who get the flu have mild illness. However, severe cases can be deadly. 

A person with the flu can spread the virus when they cough, sneeze, or speak with other people from a close distance. You can catch the flu by touching a surface contaminated with the virus and then touching your mouth, nose, or eyes.

Getting a yearly flu vaccine is the best protection against infection for everyone age 6 months or older. Eligibility for different types of flu vaccines is determined by your age, health, and any allergies to the flu vaccine or its ingredients.

Read more about the flu from the CDC here.