What is flu?
Influenza, also called the flu, is a contagious respiratory illness caused by influenza viruses. It can cause mild to severe illness and at times lead to death.
Influenza viruses cause disease among all age groups. Rates of infection are highest among children. Yet, rates of serious illness and death are highest among the elderly, children less than two, and persons of any age who have medical conditions that place them at increased risk for influenza complications.
The best way to prevent the flu is to get a seasonal flu vaccination each fall.
How Flu Spreads
Flu, a contagious disease, is mainly transmitted from one person to another by respiratory droplets which occur during coughing, sneezing, talking. Less often, a person might get flu by touching surfaces contaminated with the flu virus and then touching your mouth or nose.
You can pass on the flu to someone else before you know you are sick, as well as while you are sick. Adults can spread the flu up to one day before symptoms develop and five to seven days after becoming sick. Some people, especially children and people with weakened immune systems, can spread the flu for an even longer time.
Symptoms of flu
People who have the flu often feel some or all of these symptoms:
- Fever (Not everyone with flu will have a fever)
- Feeling feverish/chills
- Cough or sore throat
- Runny or stuffy nose
- Muscle or body aches
- Fatigue (extremely tired)
- Vomiting and diarrhea (more often happening among children than adults)
Complications of flu can include bacterial pneumonia, ear infections, sinus infections, dehydration, and worsening of chronic medical conditions, such as congestive heart failure, asthma, or diabetes.
Certain people are at greater risk for serious complications if they get the flu. This includes older people, young children, pregnant women and people with certain health conditions* (such as asthma, diabetes, or heart disease).
High risk population for developing flu-related complications
- Children younger than 5, but especially children younger than 2 years old
- The elderly over 65 years of age
- Pregnant women
- American Indians and Alaskan Natives
- People who have medical conditions include, but not limited to:
- Neurological disorders
- Chronic lung disease
- Heart disease
- Organ disorders (e.g. kidney disorders, liver disorders)
- Weakened immune system due to disease or medication (such as people with HIV, AIDS, or cancer)
- People who are morbidly obese (Body Mass Index [BMI] of 40 or greater)