I thought some of you might find this interesting, Random Flu Thoughts. The last part has a pretty good, if elementary, illustration of the importance of base rates.

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The author lists this under 'dumb associations':

The other theme is that they, or someone they knew, had the vaccine and shortly thereafter had some adverse reaction attributed to the vaccine. Like the paranoid conspirators, the idea that the vaccine caused the subsequent disease is not amenable to logical refutation. It is a motto in the skeptical world that association is not causation, but it is a concept that is paid little attention.

Who has taken the flu vaccine regularly and not had an adverse reaction, ever? I think it's biased to dismiss all of this real world, empirical evidence because it doesn't fit under your moral argument that HCWs should take it to protect their patients (which I agree with). Instead, scientists that are more familiar with our immune responses should help up put these adverse reactions in context. Without information, my reaction to the vaccine this year was bad enough I probably won't take it again.

The most sick I have ever been was the day after I got my one and only flu shot (it contained a vaccine for H1N1 and two other strains in a single shot). Was it from the shot? Well, it is some evidence, but not enough to outweigh large studies involving thousands of people.

to outweigh large studies involving thousands of people.

I don't think the studies conclude that there are no adverse reactions. In fact, I think I recall being warned that there is a probability of a reaction. This site corroborates the first-hand and second-hand emprical data I've collected. Including yours, just now, for example a similar thing happened to my father when he took a pneumonia vaccine and the flu vaccine together this year, though it had never happened before. Also, I've lost my voice after taking the flu shot each time, and this has happened to my mother-in-law as well. I'm heartened to see that 'hoarseness' is a listed symptom.

I see. Thanks for the link.

I have had the flu vaccine almost every year since I was a kid (currently 25); I do not recall ever having an adverse reaction.

I have had the flu vaccine regulary for the past 5 years and have never had an adverse reaction. Further how are you sure the "reactions" you are having are from the vaccine?

Further how are you sure the "reactions" you are having are from the vaccine?

Sometimes it is clear that the reaction is from the vaccine, for example, if you arm is sore at the location of the flu shot injection of if you get dizzy and need to sit for 20 minutes in the doctor's office with monitoring. Other times it is less clear, possible reactions have to be taken in the context of how likely they are to occur randomly and how temporally linked they are to the shot. (For example, I wouldn't believe flu-like symptoms occurring a few weeks later is due to the shot.)

This is why we do population studies and don't rely on anecdotes because we cant be sure otherwise if the cause is due to a vaccine or randomness.

Well yes that context matters which is why I wondered how he new the reaction was due to the vaccine