Health officials' warning this month of a potentially harsh flu season should be a red flag to avid aerobic-bunnies and gym-jocks alike. The Centers for Disease Control (CDC) warn that the flu is transmitted when flu virus in the air is inhaled after an infected person coughs, sneezes, or speaks. Transmission also occurs when a person touches a surface that has flu virus on it and then touches his or her nose or mouth. Those familiar with the typical health club milieu, then, can easily liken a workout in the gym to sitting in a veritable Petry dish

Heavy-breathing members on closely-placed cardiovascular machines and in crowded group fitness classes, hundreds of kinds of shared equipment from dumbbells and weight plates to public restrooms and the corner water fountain provide countless opportunities for contact with the flu virus. So, short of ditching our fitness goals until mid-Spring, it would do us well to learn more about the flu, it's prevention, and what we can do about it.

What is the flu?

The flu, or influenza, is a contagious disease caused by the influenza virus. It attacks the respiratory tract in humans (nose, throat, and lungs). The flu is different from a cold; it usually comes on suddenly and may include these symptoms:

• Fever
  

• Headache
  

• Tiredness (can be extreme)
  

• Dry cough
  

• Sore Throat
  

• Nasal congestion
  

• Body aches
  

About 10% to 20% of U.S. residents will get the flu each year. Among these persons infected, an average of 36,000 will die, and 114,000 will be hospitalized. Although the CDC claims it is not possible to accurately predict the severity of the flu season, this year's early incidence of Type A flu strain is historically associated with a more severe flu season, including higher numbers of related hospitalizations and deaths. To make the outlook more grim, an epidemiological assessment by the Centers for Disease Control (CDC) already reports "widespread" influenza activity in over 10 U.S. states.

Who is at risk?

Although anyone can get the flu, including individuals who are healthy, there are various groups who are at higher risk for complications. These high risk groups include:

• persons aged > 50 years;
  

• residents of nursing homes and other long-term care facilities that house persons of any age who have long-term illnesses;
  

• adults and children > 6 months of age who have chronic heart or lung conditions, including asthma;
  

• adults and children > 6 months of age who need regular medical care or had to be in a hospital because of metabolic diseases (like diabetes), chronic kidney disease, or weakened immune system (including immune system problems caused by medicine or by infection with human immunodeficiency virus [HIV/AIDS]);
  

• children and teenagers (aged 6 months to 18 years) who are on long-term aspirin therapy and therefore could develop Reye Syndrome after the flu; and
  

• women who will be more than 3 months pregnant during the flu season.
  

How to Prevent Getting the Flu

Health officials are encouraging people, particularly those in high-risk groups to obtain a flu shot. The CDC states that an annual flu shot is the best way to reduce the chances that you will get the flu.

The best time to get a flu shot is from October through November, although you can still benefit from getting the vaccine after November, even if the flu is present in your community. Be aware that it takes about two weeks after the vaccination for antibodies to develop in the body to provide protection.

Obtaining the vaccine does not guarantee a flu-free season, however. Influenza viruses are constantly changing, and vaccine effectiveness depends on the match between vaccine strains and circulating viruses and the age and health status of the person getting the shot. Although the strain in this year's flu vaccine is different from the circulating strain, the CDC states that studies indicate that the vaccine should provide some cross-protection against the circulating A strain.

Some people resist getting the flu shot because of the belief that they will get severe side effects, or even the flu itself, from the vaccine. The viruses in the vaccine are inactivated, so you cannot get the flu from a flu shot. Certain side effects are possible, such as soreness, redness, or swelling where the shot was given, fever (low grade), and aches.

Chances that the shot will cause serious harm, or death, is very small and allergic reactions to the vaccine, though possible, are rare, states the CDC. Most people who get the vaccine have no serious problems with it. However, the following groups should not get a flu shot before talking with their doctor:

• People with an allergy to hens' eggs.
  

• People who have had a severe reaction to a flu shot in the past.
  

• People who have developed Guillian-Barre Syndrome in the 6 weeks following a flu shot.
  

Since obtaining vaccination doesn't necessarily guarantee immunity against the flu, it is wise to add common sense to our prevention efforts while we are busy pumping iron at the health club. Old fashioned hand-hygiene can go a long way in helping to prevent flu transmission. Although you don't want to spend your entire workout running to the restroom to wash your hands after every set, it's certainly advisable to make sure your hands are clean before and after the workout. Refrain from touching your nose and mouth during the workout to avoid obtaining the virus. Use of hand-antiseptics which include alcohol can also help to prevent transmission of the flu virus.

What to do if you get the flu

So what if you obtain a flu shot, practice stellar hand-hygiene and manage to contract the flu anyway? Since it is impossible to tell if you have the flu based on symptoms alone, visit your doctor. Tests can be performed in the first few days of the illness to determine the diagnosis. Since influenza is caused by a virus, antibiotics won't work to cure it. You need to rest, drink plenty of fluids, avoid using alcohol and tobacco, and possibly take medication to relieve symptoms.

The CDC warns never to give aspirin to children or teenagers who have flu-like symptoms, particularly fever, without speaking to your doctor. Doing so can cause a rare but serious illness called Reye syndrome.

By all accounts, we may be in store for a particularly harsh flu season this year. Take precaution to reduce the likelihood of getting the flu, particularly if you are an avid gym-goer. Preventative measures may not only help to avoid the flu, but also interrupting hard earned progress on your fitness goals.

For more information about the flu, it's transmission, prevention and treatment, check out the CDC website at http://www.cdc.gov/ncidod/diseases/flu/.

Jon Gestl, CSCS, is a personal fitness trainer and instructor in Chicago specializing in in-home and in-office fitness training. He is a United States National Aerobic Champion silver and bronze medalist and world-ranked sportaerobic competitor. He can be contacted at jongestl@jongestl.com.