iayork at panix.com (Ian A. York) wrote:
>First, I don't think it's a case of primary vs. secondary infections.
>Adults infected with VZV for the first time tend to have more severe
>responses than do children infected for the first time. The same is true
>for some other herpesviruses - e.g. Epstein-Barr virus - but I don't
>think it's universally true: I'm not aware of anything suggesting this is
>true for herpes simplex, for example (though I may be wrong).
A good point I was not aware of all of those examples.
>Second, while immunoregulation is almost certainly involved in the
>pathogenesis (and incidentally, I'd tend to say that probably all
>herpesviruses are immunomodulators, but the specific functions haven't yet
>been identified for many) the role of this immunomodulation is not
>necessarily predictable. Experience with some other viruses (adenoviruses
>and some pox viruses) suggests that removing immune regulatory genes from
>the virus can lead (perhaps counterintuitively) to a more severe disease.
I couldn't agree more. I too am certain that most, if not all
herpesviruses are immunoregulatory.
>I'd tentatively suggest, actually, that one reason for the more severe
>disease is the contribution of a more competent immune system in adults
>to the symptoms. (This presumes that at least some of the symptoms of
>the disease are immune-mediated. I think this is probably true, but I
>don't know that it's been looked at very closely.)