I randomly saw this post, thought I would put my two cents in:
Like marbles suggested, the genetic "changes" do not get transferred to offspring. This is mainly because an offspring genetic make up is dependent on the mom and pops sex genes which do not carry over DNA adaptations from viral infections. Your body independently of this scenario by producing antibodies(Ig) as part of an active immune response. Antibodies are stored for later use subsequent to an infection. These antibodies are not transferred from mother to fetus through the placental barrier with the exception of IgG. There are a total of 5 type (IgG, IgA, IgM, IgE)(GAME) and IgD which encompass a comprehensive adaptive response to attach a sort of variations of viruses.
The child may inherit a natural resistance to a particular disease, but that is not the same thing. In answer to your question, if every child whose mother had chicken pox became immune to that illness, then within a couple of generations chicken pox would cease to be able to infect humans. So, although I can not answer your question scientifically, I can answer it logically. Having said that, it is well known that nursing mothers pass on this sort of protection to their infants - for that period of time that the infant is nursing.