No, you don't have to, since this is a response driven virus, not something that is being actively tracked. If it was a virus being actively tracked, you would see a spike in various spam emails.
In my experience, once you clean it up, you don't have future problems unless you open something from a friend again with the type of stuff like I described above who reinfects your machine. When that happens, you just have to go through the cleanup process again. This is what happened to my friend that took 3 months to clean up.
We all now know what to look for so we just trash them when they come in and immediately email the friend back to let them know they have had their email spammed so they can debug their machine and not spread the problem further.
Hope this helps! My family has been in IT for most of our lives and this is a relatively minor problem, mostly just a nuisance.