Is the Swine Flu Vaccine for You?

Answering those questions can be harder than you'd imagine.

The swine flu—more accurately, the 2009 H1N1 virus—has changed the way many of us think about viruses and vaccines. And many are still struggling to understand a virus that is described in one breath as a deadly global pandemic and in the next as hardly different from seasonal flu.

It's no wonder we're confused.

People who shun the swine flu vaccine tend to fall into two categories: those who aren't concerned about swine flu, and those who are concerned about the vaccine's safety.

Those who don't view swine flu as a serious health risk cite the relatively mild-to-moderate symptoms experienced by many who have contracted the H1N1 virus. A Tennesee mother of two told the Associated Press, "Basically, the swine flu is the flu. I'm not overly excited about it." And for people who don't typically get the seasonal flu, flu shots can seem superfluous. "I never got the flu vaccine. I've never had the flu before—super immune system I guess," says one BabyZone community member.

Meanwhile, those who question the swine flu vaccine's safety cite a variety of concerns.

Some are anxious about thimerosal, a mercury-based preservative used in roughly 60 percent of the swine flu vaccine doses to be distributed in the US. In July 1999, as a precautionary measure aimed at limiting exposure to mercury, the US moved to eliminate, or seriously reduce, the amount of thimerosal in routine childhood vaccinations—but thimerosal is still used in some other vaccines, including flu shots. Some people believe there are ties between thimerosal and autism.

Others are concerned about Guillain-Barré syndrome (GBS), a rare auto-immune disorder that caused serious symptoms, including paralysis, in 500 or so of the 40 million people who were vaccinated during the 1976 swine flu immunization campaign. Experts are not sure what triggers GBS—although it is known to strike those who have recently had some kind of respiratory or gastrointestinal illness— and there is no known cure. Studies suggest that roughly one out of 1 million vaccinated persons may be at increased risk of developing GBS.

Additional concerns focus on the rapid development of the vaccine. Those concerns include the possible long-term side effects and whether the H1N1 flu vaccine was rushed to market without being sufficiently studied.