The flu is a contagious respiratory illness caused by influenza viruses that infect the nose, throat, and lungs. It can cause mild to severe illness, and at times can lead to death. The best way to prevent the flu is by getting a flu vaccine each year.

People who have the flu often feel some or all of these symptoms:

*It is important to emphasize that not all people with the flu have a fever. Flu viruses spread through droplets that form when people with the flu cough, sneeze, or talk. These droplets can land on the mouths or noses of people nearby.

It is much less common to catch the flu from surfaces and objects contaminated with flu viruses, which, after being touched, can transfer the viruses to the mouth, eyes, and possibly the nose.

You may be able to pass on the flu to someone else before you know you are sick and, of course, as well as while you are sick. Most healthy adults may be able to infect others beginning 1 day before symptoms develop and up to 5 to 7 days after becoming sick. Some people, especially young children and people with weakened immune systems, might be able to infect others for an even longer period.

The time from when a person is exposed to flu virus to when symptoms begin is about 1 to 4 days, with an average incubation period of about 1 day.

Flu complications include bacterial pneumonia, ear infections, sinus infections, dehydration, and worsening of chronic medical conditions, such as congestive heart failure, asthma, or diabetes.

People at high risk from flu
Anyone can get the flu, even people without comorbidities. Serious problems related to the flu can happen at any age, but some people are at high risk of developing serious flu-related complications if they get sick.

• This includes people:
• 65 years and older;
• people of any age with certain chronic medical conditions (such as asthma, diabetes, or heart disease);
• pregnant women;
• young children.

The first and most important step in preventing flu is to get a flu vaccination each year. Everyday preventative actions (like staying away from people who are sick, covering your mouth when you cough and sneeze and frequent handwashing) are also recommended to help slow the spread of germs that cause respiratory illnesses (i.e. of the nose, throat, and lungs) and flu.

There are antiviral drugs that can be used to treat flu illness. Those are oseltamivir, zanamivir and peramivir. It is important to consult a doctor or pharmacist before taking any medication.

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