Depends.
If the virus is in an attached file, then in all liklihood, no. Don't
open the mail and certainly don't open the attached file. Delete.
If the mail is HTML formatted mail, and you have configured outlook to
download the components, then a whole lot of other things are possible.
Surely it is easy for your privacy to be invaded, and I read about the
possibilty of nefarious programs being executed. Just don't open HTML
from sources you don't know or trust, and don't contribute to the
problem by sending your own mail in html format.
Hope this is useful to you. Let us know.
rms