so many legal-eagles on this board that i’ll throw my dice and see if i can scrounge up some bio types to answer this question…and no, i don’t want to know where i can rustle some up.
i was vaccinated against smallpox in 1979 (hence the username) as an infant because i was born in India and if i remember correctly WHO was requiring most of the third world to vaccinate against smallpox until 1979 or 1980 (my sis was born in india in 81 and didn’t have it done to her)…i was among the last batches of babies to get this deal. i think i have the standard vaccine…i have a round scar on my upper thigh where they took my chunk o’ flesh and whatnot so maybe you can gauge from that. my question is: Is this vaccine still effective? Is it effective only for a certain length of time or is it effective for life? My reason for asking is that on another board I read that the smallpox vaccine is only effective for 5 to 10 years. I’m intrigued to know-my rather limited knowledge of biology led me to believe that I was good for the rest of my days.
Thanks in advance 
Nope. It’s only good for about 10 years or so.
You don’t believe the answers to your questions on eurotrip anu? Not nice!
nice job stalker b :). who are you? wendy b? can’t be niwroc 'cause he has the same handle. cil? trylo? brandipandi?
i didn’t ask a question e-tripper…remember i stated that i would be safe while all of you guys croaked and then toon chimed in and said i was as doomed as “you lot,” but i wasn’t about to take my medical advice from an overly hysterical engineer.
The CDC says that the vaccinations of people done prior to the end of mass vaccinations are not known to be effective, and are therefor assumed to be ineffective. The five-year period of effectiveness is often quoted, because other vaccinations tend to have a reduced efficacy after that.
Tetanus, for example is now routinely readministered if a risk factor is incurred after five years has passed since the last inoculation. Previous doctrine held that ten years was adequate. The differences in efficacy are not so sharp as might be supposed from that change. Certainly the body’s response could be expected to be less vigorous. How much less is a variable.
However, hard data on the duration, and pattern of loss of effectiveness of smallpox vaccinations is not available. The program the successfully eliminated the disease worldwide was run under the assumption of a lifetime immunity from a single vaccination. Those of us who were vaccinated multiple times over the first twenty years before the cessation of vaccination may well have a residual resistance. But you don’t count on that, if you know of an outbreak. You vaccinate everyone within a certain distance of the known cases. (In our society, that distance is very large, in miles, but recently, much smaller in pure numbers.)
Tris
“I believe in general in a dualism between facts and the ideas of those facts in human heads.” ~ George Santayana ~
10 years is considered the standard lenght of effectiveness. Buy why would you ask lawyers instead of doctors? DPW, J.D.
So here’s a bio-type reply to the question.
When you are vaccinated, some of the B-cells in your body become “memory cells”. They have a antibody to small pox (or whatever) and sit around in your blood stream waiting for small pox (or whatever) to bind to the antibody. If you are infected with small pox, they say “aha!, something just bound to my antibody!” and they start churning out both new cells with the same antibody and the free antibody itself (this is oversimplfied, but good enough) and your body fights off the infection.
However, the “memory cells” do not have an infinite lifespan. If they are never activated (i.e. have something bind to their antibody) they eventually die off. How fast this happens depends on how old they were to begin with, your health, personal physiology, etc… So while some people will be lucky enough to still have viable “memory cells” 20 years after a vaccination, most will not. Hence, the somewhat arbitrary time limit of 10 years - it’s when most people would need a booster.
The other side of this is that for common diseases, you will keep your immunity. Every time you are exposed, the memory cells will create new memory cells with the same antibody, and so you are effectively being re-vaccinated. Boosters and re-vaccination do the same thing. Sometimes, a disease which is not the one you were vaccinated for is still close enough that it activates your memory cells and gives you a booster, even though it is not the same pathogen. There is evidence that cowpox (a cow disease, does not cause sickness in humans) exposure can cause/maintain smallpox immunity, due to cross-reaction of similar antibodies.
Hope that helps!
mischievous