Time for the Flu Vaccine

At a list price of $25, Fluzone High-Dose is costlier than the standard vaccine, which goes for around $11. Both, however, are covered by Medicare part B with no copayment. There are ample supplies of the vaccines this year, according to the CDC.

Afraid of needles?

The main selling point of Fluzone Intradermal (listed at about $15.50) is that its very short, slender needle merely pricks the skin — a painless, simple-to-administer "micro-injection" that maker Sanofi Pasteur hopes will find widespread acceptance and help increase flu vaccination rates.

Because the injection goes into the skin, an area rich with cells that play an important role in immune response, it produces about the same antibody response as the standard shot, but with 40 percent less active ingredient. That could prove a boon in any year when vaccine is in short supply.

The CDC recommends that everyone age 6 months and older get a yearly flu vaccine, except in a very few cases like a severe allergy to eggs. This program for near-universal vaccination was introduced last flu season, when manufacturers shipped a record number of doses to U.S. pharmacies and doctors' offices.

Even though the flu season doesn't usually peak until late January or early February, people should get the 2011-2012 vaccine as soon as it's available in their location, says CDC spokesperson Jeff Dimond.

The shot provides immunity against the same three strains of influenza as last year's vaccine. Public health authorities predict these strains, including the 2009 pandemic "swine" flu strain, will predominate again this flu season. CDC officials say that because vaccine-induced immunity wanes over the course of a year, those vaccinated last year need to get another flu shot this season.

Getting vaccinated is the cornerstone of flu prevention, says Nichol, but it's not perfect and won't protect everyone equally.

For those who may not get complete immunity from the vaccine, it's key for other people in the community — coworkers, grandchildren, health care personnel — to be vaccinated also, both for their own protection and to prevent the spread of flu germs. And the old advice remains some of the best: "In addition to getting vaccinated," says Nichol, "wash your hands frequently, cover your cough, stay home when you're sick and avoid exposure to others who are sick."

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Katharine Greider lives in New York and writes about health and health policy issues.