Last week I went with Holly to her appointment with the midwife where we heard the baby's heartbeat for the first time. Holly is starting to show a little, and this morning I was able to feel the top of her womb. She'll have another ultrasound in a few weeks. Holly has had some occasional queasiness, but no serious morning sickness. So, everything is going very well!
Guillain-Barré syndrome (GBS) is an inflammatory disorder of peripheral nerves, causing muscle weakness and sensory changes (tingling or burning sensation and/or pain). About 70% of cases are preceded by a ‘trigger’ event, usually occurring 1 to 3 weeks before the onset of symptoms. One of the most common trigger events is an upper respiratory infection - including influenza.
The incidence (number of new cases) of GBS is estimated to be 1.8 per 100,000 population per year. In the United States, there around 6,000 new cases of GBS every year.
In 1976, there was an increase in the incidence of GBS among the recipients of the 'swine flu' vaccine of about 1 case per 100,000 vaccine recipients. In 2004 the Institute of Medicine concluded that there was sufficient evidence of a causal relationship between the 1976 'swine flu' vaccine and GBS, but the reason has not been determined.
Since 1976, vaccine production methods have changed, resulting in fewer side effects. Most studies have found no association between GBS and influenza vaccines manufactured after 1976, but a few studies suggest that there may be an additional one case of GBS per one million influenza vaccine recipients. Since influenza is a trigger event for GBS, a protective effect from the vaccine against GBS cannot be ruled out.
When considering the possible side effects of a vaccine, it's important to consider the risk versus the benefits. The attack rate for influenza during flu season is 10% to 40%. In contrast to a possible 1 additional case of GBS per one million vaccine recipients, the hospitalization rate for 2009 H1N1 was 222 per one million and the death rate was 9.7 per one million cases. Pregnant women are at much higher risk for hospitalization and death from influenza than the general population. GBS is a condition from which most people completely recover.
I've never bought a lottery ticket because the probability of winning is low. I don't worry about GBS when I take a flu vaccine because the probability of developing GBS as a result is either nonexistent or extremely low. I'm much more likely to miss work or be hospitalized because of the flu.
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