If I recall my biology class lessons correctly (help me on this, BW), isn't it true that the way viruses and bacteria infect is by sensing certain points (proteins?) on a cell. Now, theoretically, if those specific proteins wre missing, the virus wouldn't have anything to "latch on to"
Now, if this is true, then it would depend on what happened to the human when he became a werewolf. Would he have the points of a human, and the wolf have those points, or vice versa? Both? In a sense, it would be cinematic at this point, as we don't yet know what would happen to the WW.
Regarding heart attacks, I would think that it would depend on the size of the WW form. If the WW is larger, then the cholesterol would probably be at the very least dislodged, perhaps cycling to somewhere else. However, I would tend to look at it as an evolutionary thing. Kind of. When you consider the fact that if they were able to evolve and biologically learn to get the cholesterol in the blood cycled to "a certain point", and use that first, the WW would have a greater chance of living (Just enough energy at *that* moment).
On the other paw, there's the fact that the human would consider this a release, if not of the right mentality, and the eat into the high excess. Then they would most surely be either having the cholesterol clog at some point, causing a heart attack as the veins grew somewhat larger.
Or so it'd seem to me.
![Sweat drop. :sweatdrop:](./images/smilies/sweatdrop.gif)
You can run, you can hide, but I'll still pounce on you and lick you silly.