Zarf BeebleBrix: "IF your immune system weakens, chicken pox can come back. However... as for "wearing off," I'm calling BS. Chicken pox isn't like smallpox in that it doesn't exist anymore: The disease is still in existence among the population. Therefore, your body is reintroduced to chicken pox constantly, which allows it to renew that fight against the disease."
Vaccinations can wear off, some are more prone than others. This does not mean, of course, that the immunoglobulins will disappear, my main point was that immune systems can become impaired (and for a variety of reasons). Moreover, VZV is not just amongst the population, once you've had it it remains dormant within your body. There is always the possibility of an opportunistic infection, however unlikely the general probability is.
"It's simple: There's two different types of viruses: Mutating viruses (i.e., influenza), and non-mutating viruses (chicken pox, smallpox). If smallpox were a mutating virus, it could never have been eradicated in the '60's, because the disease would change year after year, just like influenza does, making old antibiotics useless."
You're wrong on a lot of levels. There is no such thing as a non-mutating virus, please do not spread such misinformation anymore. You're ignoring the fact that viruses such as smallpox, chicken pox, and polio affect (or used to affect) mostly children. Their evolution is stagnated because the population density is sufficient enough that they are never without new hosts to infect. The vaccinations for these viruses are only so effective because of their widespread distribution /and/ the virii's inability to adapt in time. Other viruses, like influenza and HIV/AIDS, are much more agressive insofar as they have intermediary hosts, more pathways for infection, and a higher rate of mutation. The pathogens from these "aggressive viruses" can easily evade even our body's built-in defenses.
"And aside from that... I can agree with everything you said, and it doesn't answer the underlying question which I was challenging you on: That not all diseases mutate."
Correct, not all diseases mutate. Viruses and bacterium on the other hand /do/.
~Pw 32~ Random Hero: "You guys speak on this, as if your doctors ... left it alone you know nothing"
Thank you for your input. You're right, /I'm/ not a doctor. I did, however, major in molecular evolution. Virology, although not the focus, is closely related to the study of evolution at the molecular level. Lateral gene transfer, for example, is of particular interest in both fields.
Caution Wake Turbulence
