Influenza, or the flu, is a respiratory illness. It is seasonal, and is spread from person to person from coughing or sneezing. Influenza is highly contagious and is caused by the influenza viruses, mostly A and B. Symptoms are similar to the cold, but is worse and lasts longer. The most common flu type that humans get is H1N1, which is an Influenza type A, and can infect animals as well as people. Influenza Type B are normally only found in humans, along with Influenza Type C. Influenza Type C is not very common and is mild. Bird flu is listed as a type A Influenza.

The only way to avoid getting influenza is by getting the vaccination each year. Severe cases of influenza can lead to hospitalization and even death. The flu is treated with antivirals. Sometimes, the cough from the flu does not go away, and doctors may treat this with asthma medications. But if you do not have a severe case of influenza, you can treat yourself at home by getting plenty of rest and fluids, and being sure to stay home to prevent from spreading the illness. Over the counter medications may help ease your symptoms as well.

Between 3,000 and 49,000 people die each year from influenza. Your complications from the illness are worse depending on what kind of health state you are in prior to getting the flu. Elderly people and people with lung diseases such as asthma, or other conditions that are chronic, are at a higher risk of complications. Between 5 and 20 percent of people get the flu in the United States each year.  According to the CDC, more than 146.2 million doses of the flu vaccine have been distributed in the United States.

http://www.lung.org/lung-health-and-diseases/lung-disease-lookup/influenza/learn-about-influenza.html

http://www.cdc.gov/flu/

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