This thread is for asking any questions that might seem obvious, tangential, silly or what-have-you. Don't be shy, everyone has holes in their knowledge, though the fewer and the smaller we can make them, the better.
Please be respectful of other people's admitting ignorance and don't mock them for it, as they're doing a noble thing.
To any future monthly posters of SQ threads, please remember to add the "stupid_questions" tag.
Moreover, which vaccines are worth getting? For example, is it worth getting a meningococcal vaccine if you're not in any of the major risk groups?
Many universities strongly encourage their students to get the meningococcal vaccine (as sleeping in rubbish communal bedding is a risk factor), but for something really rare, even the risk involved in traveling to the clinic to get vaccinated could have more disutility than the protection the vaccine might provide would be worth.
The meningococcal vaccine causes a fever 3% of the time, and a few days of mild to moderate discomfort 60% of the time. If it causes any other problems in healthy people, the CDC hasn't documented it.
Outside of major risk groups, this vaccine decreases your chances of getting meningococcal disease by some low amount, less than one in a million annually. If you get the disease, there's a 10% chance of dying and a further 10% chance of being permanently disabled in some severe way. This is less than a tenth of a micromort.
The bacteria that causes meningoccoal disease is ubiquitous (10% of people are carriers), so other benefits of vaccines, such as herd immunity, would require extreme measures to obtain.
Driving causes about 1.5 fatalities per 100 million miles traveled, according to FARS, so this particular vaccine actively averts about as much risk as is involved in driving ten miles a year, which may or may not be worthwhile, but it certainly isn't a low-hanging fruit in terms of risk aversion.
Anyway, let's tally it all up:
Meningococcal vaccine utility:
0.00001% lower individual chance of getting meningococcal disease per year (minus 0.1 micromorts/year = at best a few minutes more of expected healthy lifespan, unless we solve the aging problem)
increased herd immunity (negligible due to the nature of this particular disease)
Meningococcal vaccine disutility:
mild discomfort
3 to 5% chance of fever
whatever risk is involved in traveling to the clinic (could be several minutes less of expected healthy lifespan)
whatever time it takes to get the vaccine (a few minutes to over an hour) could be spent doing something else
any undocumented risks that the vaccine itself might have (What are these?)
risk of physician error (What is this for a simple injection?)
Obviously, a lot of this will vary depending on the vaccine and the disease it's meant to prevent. Some diseases pose higher risk, as do some vaccines. I didn't get all of the standard vaccinations as a child because I was too severely allergic to some of them.
It might be helpful to do this sort of calculation for every available vaccine, but it's a bit tedious. I haven't found anywhere that lists the necessary information in anything resembling a convenient format.
Don't you need to include the risks of a)being in an undiagnosed high-risk group, and b) developing a condition that puts you in a high-risk group?
Also, in terms of the driving risk, don't you need to understand that in terms of substitution (I think that is the right term)? In other words, when calculating the driving risk, it becomes complex because time in the car going to the clinic may/very likely will be bundled with other driving (going to the clinic for other services, going to a store afterwards, etc.), so you can only include driving risk for this vaccine if it would not have been substituted for by other driving.