Skip to content

Cold, Flu, & Cough Health Center

Font Size

5 Reasons Some People Fear the Swine Flu Vaccine

Experts explain why many Americans say they won't get this year's H1N1 swine flu vaccine.

Fear No. 2: Swine Flu Vaccine Is Too New to Be Safe continued...

What's different about the H1N1 swine flu vaccine is that the viral particle recognized by the immune system -- the vaccine antigen -- comes from the "H1" part of the swine flu virus rather than the "H1" part of the seasonal flu virus. H1 can't give you the flu and is not toxic.

But what about the swine flu vaccine of 1976? As many people now recall, there was a flu vaccine in 1976 that might have had safety issues. That vaccine may have triggered a rare but devastating neurological syndrome called Guillain-Barre syndrome (GBS) in as many as one in 100,000 vaccine recipients -- and 44 million people got that vaccine.

"In the mid-1970s, when that swine flu vaccine was given, there were about 25 to 50 cases of GBS," Epperly says. "GBS is a demyelinating neuropathy. People don't know what that is, but it's left a lingering fear the 2009 H1N1 vaccine may do more harm than good."

It's still not clear what happened in 1976. Some scientists say the vaccine wasn't linked to GBS, others say it was. But there have been huge improvements in flu vaccine production since 1976. There's much better testing for contaminants such as the suspected bacterial contaminant in the 1976 vaccine. Viral particles are purified differently. And quality testing is greatly enhanced.

Moreover, the 2009 H1N1 swine flu is a very different bug than the 1976 swine flu. For one thing, it's causing a very real pandemic. The 1976 virus never broke out of the army base where it was first detected. Historians have called it "the pandemic that never was."

No matter how small the risk of the 1976 vaccine, there was zero benefit. That's not the case now. Hundreds of Americans already have died of 2009 H1N1 swine flu, and the bug already has circled the globe. Nearly every nation on earth would like to have as much of the vaccine as the U.S. has.

Vaccine supplies in many nations -- Canada and the U.K., for example -- have approved the use of a substance called adjuvant to boost immune responses to the vaccine. This oil-in-water emulsion is approved by European regulatory agencies, but not yet by the FDA.

Consequently, no adjuvant is being used with the U.S. H1N1 swine flu vaccine. The U.S. does have a large supply of adjuvant. It might be used if the virus mutates and a broader immune response is needed for vaccine protection. But that has not happened yet, and may never happen at all.

Today on WebMD

hot toddy
15 tips to help you feel better.
man sneezing into elbow
Do echinacea and vitamin C really help a cold?
teen girl coughing
Get a good night’s rest with these remedies.
elder berry
Eat these to fight colds, flu, and more.
Natural Cold Flu Remedies Slideshow
cold weather
Allergy And Sinus Symptom Evaluator
Boy holding ear
woman receiving vaccine shot
woman with fever
Waking up from sleep
woman with sore throat