Nearly half of Americans say they're going to skip the flu shot this season, according to a nationally representative survey of 2,011 adults conducted by the Consumer Reports National Research Center in October. And parents who avoid flu shots themselves seldom get their kids vaccinated either, our survey found, even though the Centers for Disease Control and Prevention now recommends that everyone age 6 months and over should get the shot each year.

People who get vaccinated cut their risk of developing the disease by roughly 20 to 90 percent, depending on their age and overall health, as well as how well the vaccine matches the flu virus that actually emerges. And even when the shot doesn't prevent the flu it often makes the symptoms less severe, making it less likely that you'll have to skip work or that your kids will miss school, or that you'll have to be hospitalized.

At least as important, getting vaccinated reduces the chance you'll spread the disease, which is an especially good reason for kids to get the shot, since they're often the ones who bring the germs home. And it's vital if you live or work with older or frail individuals, since they're particularly vulnerable to the complications of the flu.

The best time to get vaccinated is now, so you'll be protected by the time flu season reaches its peak, usually in February. (To see how much you know about the flu shot, take our online quiz.)

Despite those benefits, 45 percent of the people in our survey said they were opting against the vaccine this year, usually for any of several poor reasons. For example, nearly two-thirds of the flu-shot skeptics said that it's better to build your own natural immunity against the flu. But, as we explain in “12 top excuses for skipping the flu shot are exposed,” that argument doesn't stand up.

People who are opting for the shot had two particularly encouraging pieces of news that might persuade some flu-shot abstainers to change their minds. Specifically, they found that the vaccine is:

Convenient. Fifty percent said they got or plan to get the shot at some place other than their doctor's office, including work (24 percent), a walk-in clinic (14 percent), or a pharmacy (7 percent).

Cheap. For 65 percent of our respondents, the flu shot was free, in part because Medicare now covers it entirely. For those who did have to pay, 90 percent had to shell out less than $30.

Even the people who got the shot know that it doesn't guarantee protection—just lessens the odds. That's why more than 90 percent of them said they take other steps to protect themselves during the cold and flu season. Some of those measures, such as washing hands more frequently (81 percent), clearly are worth the extra effort. But certain others, such as popping vitamins or minerals (60 percent), probably aren't. For more on what else you can do to prevent the flu, see our November 2008 report.