Influenza, (Flu)

By Roland Larrabee, M.D.

Influenza, or flu, is a virus infection of the air passages. Outbreaks of flu occur almost every year, usually in winter. Each season a different strain of flu virus may be responsible for the outbreak. In some years, the flu strain may be particularly severe and cause many deaths, particularly if pneumonia develops. There are two types of influenza: Type A and Type B. Type A flu tends to be much more severe than Type B.

How does it occur?

Flu is spread from person to person by virus-infected droplets that are coughed or sneezed into the air. In some people, a bacterial infection that causes pneumonia may also occur. This is particularly common in people who have chronic conditions, such as heart disease, asthma, chronic bronchitis, kidney disease, or diabetes. Pneumonia is one of the leading causes of death in people over the age of 65 and often occurs during and after flu outbreaks.

What are the symptoms?

Flu symptoms usually last seven to 10 days and may include:

• chills and fever (100 to 102 degrees F, 37.8 to 38.9 degrees C)
• sore eyes and throat
• runny nose
• weakness, tiredness, and muscle aches
• headache, which may be severe
• cough
• loss of appetite.
  

The symptoms of flu are easy to recognize, particularly during a seasonal outbreak. Many people tend to diagnose and treat themselves. However, you should always see your health care provider if:

• you are over the age of 65
• you suffer from heart disease, asthma, chronic bronchitis, kidney disease, or diabetes
• your symptoms become more severe, or if you begin to cough up phlegm. This may indicate you have pneumonia.
  

Most people with influenza respond well to rest, fluids, and nonprescription medications to ease symptoms. Ibuprofen or acetaminophen is useful for fever, headache, and muscle aches. Cough medicine may help your cough. If you develop pneumonia, your health care provider will prescribe antibiotic medication. If started within 48 hours of onset of your symptoms (seventy-two hours at the latest), there are anti-viral medications that can dramatically reduce symptoms and duration of the flu. To receive this benefit, you must visit your physician within this time frame. These medications include amantidine, rimantidine, Tamiflu®, and Relenza®.

For prevention, it is recommended that you have a flu shot in early fall (except if you are allergic to eggs). Because the flu virus strain varies from year to year, you need to get a new flu shot each year. Since influenza can last into the spring, it is not too late to receive the vaccine. It takes two weeks to develop protection for you. Vaccination against pneumococcal pneumonia is also important after age 65.

How can I help myself?