Influenza (aka the flu) is a contagious acute viral disease of the respiratory tract. Three types of influenza virus are recognized: A, (which includes 3 subtypes), B and C. Type A has been associated with widespread epidemics and pandemics; type B has been infrequently associated with regional or widespread epidemics; type C has been associated with sporadic cases and minor localized outbreaks. Only type A viruses are capable of mutating, (antigenic shift), causing the emergence of completely new subtypes.

The flu can cause mild to severe illness, and at times, may lead to death. It is characterized by fever, (usually high), headache, muscle aches, weakness, runny or stuffy nose, sore throat and cough.

Some people are at high risk for serious flu complications such as the elderly, young children and those with certain health conditions including pregnancy. Some of the complications caused by flu include bacterial pneumonia, dehydration and worsening of chronic medical conditions such as congestive heart failure, asthma or diabetes. Children may get sinus or ear infections.

CDC estimates that every year in the US an average of 5-20% of the population gets the flu, and more than 200,000 people are hospitalized from flu complications. Approximately 26,000 people die from the flu.


In the setting of the current vaccine shortage, CDC has developed interim recommendations on the use of antiviral medications for the 2004-05 influenza season. These interim recommendations are provided to shotreduce the impact of influenza on persons at high risk for developing severe complications secondary to infection.

Influenza antiviral medications are an important adjunct to influenza vaccine in the prevention and treatment of influenza. Influenza antiviral medications have long been used to limit the spread and impact of institutional influenza outbreaks. They also are used for treatment and chemoprophylaxis of persons in other settings.

In the United States, four antiviral medications (amantadine, rimantadine, oseltamivir, and zanamivir) are approved for treatment of influenza, though limited supplies of zanamivir are currently available. When used for treatment within the first two days of illness, all four antiviral medications are similarly effective in reducing the duration of illness by one or two days. Only three antiviral medications (amantadine, rimantadine, and oseltamivir) are approved for the treatment of influenza.



snifflesHumans are the primary reservoir however swine and birds are likely sources of new human subtypes thought to emerge through genetic changes.

Mode of Transmission:

The flu spreads in respiratory droplets produced by cough and sneezing. Airborne person-to-person spread predominates, however a person may become infected by touching something with virus particles on it and then touching their eyes, nose or mouth. The influenza virus is a very hardy virus and may persist in the environment for days -- particularly in the cold and in low humidity.

Incubation Period:

Short, usually 1-3 days.

It is important to note that you may be able to infect others beginning 1 day BEFORE getting symptoms, and up to 7 days AFTER getting sick. This means that you can give someone the flu before you know you’re sick as well as while you’re sick.

Methods of Control:

In addition to flu shots and medications there are also certain good health habits that can help control the flu:

· Avoid crowds and/or close contact with people who are sick. When you are sick keep your distance from others.

· Stay home when you are sick.

· Cover you mouth and nose with a tissue when coughing or sneezing.

· Wash your hands! It may help protect you from getting sick or from infecting others. If hand washing facilities are not readily available, the use of an alcohol type gel or spray may be employed until hands can be washed with soap and water.

· Avoid touching your eyes, nose or mouth. Germs are easily spread when a person touches something that is contaminated with germs and then touches his/her eyes, nose or mouth.

· Use a spray disinfectant on commonly touched surfaces such as telephone handles, bathroom faucets and toilet handles, and kitchen appliance handles and doors.

· Keep up a healthy lifestyle with a good diet, exercise and a full night of rest every day.

The Germ Protection Center is possible thanks to the generous support of Lysol.

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