Doctors have been saying it for years: Getting immunized against flu should be a family affair.

But many families are not heeding such advice — especially when it comes to small children.

The U.S. Centers for Disease Control and Prevention looked at data from six sites across the nation and found that less than 30 percent of children ages 6-23 months were fully vaccinated during last year's flu season. That number dropped to less than 20 percent for children 2 to 5.

Doctors said they hope more parents vaccinate their children now that the U.S. Food and Drug Administration has approved expanding use of the nasal vaccine FluMist to include children ages 2-5 in addition to people 5 to 49.

The September decision means these children can be vaccinated against flu without the needle stick many dread. And FluMist might even be more effective for them, according to a study earlier this year in the New England Journal of Medicine. The study found 55 percent fewer flu cases among children 6 months to 5 years old who received the mist vs. the shot. The mist contains weakened, live virus that doesn't cause flu but builds immunity.

If you plan on getting flu shots for your family this season, you shouldn't have any trouble.

More than 130 million doses will be available in the United States, a record number.

Meanwhile, 4.5 million doses of the nasal spray flu vaccine FluMist will be available..

MYTHS HINDER VACCINATION EFFORTS

The flu is responsible for up to 36,000 deaths each year, by some reports.

Even so, why do so many people refrain from getting the vaccine, even when it's abundant and usually covered by insurance?

Some parents are reluctant to have their children vaccinated because of their concerns over the safety and long-term repercussions of vaccines. Some parents believe there is a link between autism and thimerosal, a form of mercury used in small amounts as a preservative in most flu vaccines, even though the Institute of Medicine found no such link.

Also, many private insurers don't cover FluMist, which is not recommended for people who have asthma or compromised immune systems because of the live virus.

But the No. 1 reason, experts say, is that many Americans don't take the flu seriously. Other people don't think the flu vaccine works, despite research that show the effectiveness ranges from 70 percent to 90 percent. There's also a common myth that the flu shot causes people to get the flu.

Dr. Al Rizzo of Wilmington's Pulmonology Associates says it's biologically impossible for the flu shot to cause the flu, contrary to the popular myth. He says the vaccine introduces the body's defensive system to a dead version of the disease. The body's antibodies bind to the invader and destroy it. The shot can cause a low-grade fever and sore arm, but not influenza.

There are, however, infrequent cases where people have a poor immune response to the flu shot. And some people might catch the flu if they get the vaccine too early in the season, which typically lasts from November to February.

People who get vaccinated also might get the flu if a different strain comes along unexpectedly.

FLU TRAVELS EASILY

The flu virus is spread easily in the air through microscopic droplets, attacking people as they go about their everyday activities, like food shopping.

"If you are sick and you grocery shop, you can be touching all the other food and spreading it around," says Dr. David Bercaw, a primary care doctor with Christiana Care in Wilmington, Del. "You can be spreading it when you're giving money to the cashier. Or touching all the groceries that other people are picking out and eating. You can be touching hands, touching doorknobs, touching computer keyboards and spreading it."

Bercaw emphasizes avoiding contact with sick people during the flu season. If you do get sick, cover your mouth when you cough, but use your sleeve rather than your hand.

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