The flu is a contagious respiratory illness caused by influenza viruses. 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 vaccination each year.
Symptoms of flu include:
Most people who get influenza will recover in a few days to less than two weeks, but some people will develop complications that can be very severe.
Complications from the flu can lead to hospitalization and even death. Flu can make chronic medical conditions such as asthma, diabetes, or heart disease, worse. Healthy individuals with no chronic medical conditions may suffer from complications such as pneumonia, dehydration, ear infections or sinus infections that require additional medical treatment.
Flu viruses spread mainly from person to person by the droplets produced when people with flu cough, sneeze or talk. Sometimes, people may become infected by touching something with flu viruses on it and then touching their mouth or nose. Most healthy adults can infect others beginning 1 day before symptoms develop and up to 5 to 7 days after becoming sick. That means that you may be able to pass on the flu to someone else before you know you are sick, as well as while you are sick.
The single best way to prevent the flu is to get a flu vaccination. CDC recommends a yearly flu vaccine as the first and most important step in protecting against flu viruses.