Coming down with something? Is it the flu or a cold?

<p>'T is the season for colds and flu Contrary to what many people think, the common cold and influenza are two very different illnesses, with different symptoms.</p><p>Colds will most certainly make you miserable, but they are not life threatening and usually do not cause serious complications. Adults suffer, on average, two to four colds each year, while children may average as many as six to 10.</p><p>There are more than 200 viruses that cause stuffy noses, sneezing, sore throats and a hacking cough. These symptoms appear over a one- to three-day period and are primarily limited to the head and neck. Fevers and headaches may occur but they are not severe, and the body may ache but the aches are relatively mild. Cold symptoms usually resolve within seven to 10 days.</p><p>In contrast, influenza starts suddenly, as if you were hit by a truck. The flu is not a "bad cold." Nor is it a stomach virus with nausea and vomiting. The flu is a total body virus that knocks you flat. Each year, some 5 percent to 20 percent of the U.S.population gets the flu, and more than 200,000 people are hospitalized with complications. Each year about 36,000 people die from influenza and its complications.</p><p>One minute you feel fine, the next you are exhausted and your body hurts all over. The extreme fatigue and weakness of the flu can last up to two to three weeks. You usually have a fever that lasts three or four days, running 100 degrees to 102 degrees and occasionally higher, especially in young children. Headaches are common and you may have a stuffy nose, sneezing or a sore throat. Often there is a cough that can become quite severe.</p><p>The flu is contagious beginning one day before symptoms develop and up to five days after becoming sick, but children, perhaps due to their immature immune systems, may spread the virus for longer than seven days.</p><p>The flu shot is recommended each year as a preventive measure for anyone older than 6 months. Recent studies have indicated that even half-dose flu shots may be effective, especially in women and those younger than 50.</p><p>Viruses are particularly adept at mutating and creating new forms, so each year a new vaccine formula is designed. The possible side effects from the flu shot include soreness at the site of injection, and perhaps a mild transient fever and body aching.</p><p>Many strongly believe that the flu shot causes the flu. This is physically impossible because the shot contains inactivated (killed) particles of viruses. They cannot cause the flu because they are dead. If you get a full-blown case of the flu right after your immunization, you were exposed to the live flu virus one to four days prior to getting sick.</p><p>For those who can't take a shot, or prefer not to, there is a nasal spray vaccine that contains live, weakened flu viruses -- particles too small to cause the flu but large enough to stimulate the immune system. Because it contains live viruses, this form of vaccine may have a few more side effects than the shot: mild runny nose, headache, sore throat, or cough. The nasal spray is available for generally healthy, nonpregnant individuals between the ages of 2 and 49.</p><p>Two weeks after either the shot or the spray, the body has manufactured protective antibodies. Influenza activity usually peaks in January or later, so December is not too late to get your shot.</p><p>Dr. Stacey Kerr, a longtime Sonoma County family physician, graduated from UC Davis Medical School and is certified in her specialty by the American Board of Family Medicine. Her columns are not intended as a substitute for hands-on medical advice or treatment. Consult your health care provider before adhering to any recommendations in this column. E-mail comments to drkerr@the-doctors-inn.com.</p>