A Simple Way to Keep the Flu Away You can avoid the flu this season by taking one simple step: Get a flu vaccination. Unfortunately, some people think that getting a flu immunization is too much trouble or costs too much. Or, they swear that a flu immunization will make them sick or make them more likely to catch the flu -- or even colds. Seasonal influenza -- the flu -- is caused by one of several strains of influenza viruses (type A or B) that infect the nose, throat and lungs, making life miserable for a week or two for many people -- and deadly for some. Flu season can begin as early as October and peak anywhere from late December to early April, according to the CDC. Immunization facts Your best defense against the flu is to get immunized. Depending on your age, you can do that in one of two ways: With a flu shot, given with a needle. This form of the vaccine contains killed virus and is approved for all people older than 6 months of age. With a nasal-spray vaccine. This form contains live, weakened flu viruses that can't cause the flu. This form is approved for healthy people ages 2 to 49 years, except those who are pregnant or have diabetes, a weakened immune system, heart problems, or chronic respiratory disorders, such as asthma. Check with your doctor to see if this form of the vaccine is right for you. A flu vaccination