They don't live very long, or are they very numerous. I believe the current number of viruses for Linux in the wild that haven't died out is somewhere around zero right now.
This incident was last month. You're operating under the presumption that a virus, once defeated, will not spread automatically from that point forward. You're forgetting that viruses can be injected *manually* by someone with malicious intent.
Or, to put it in other words if the virus DBs for Windows were to decay over time so that the older definitions were removed, rest assured that someone out therre would have a copy of a 6 year old virus and pop it out the moment its definition dropped off the list.
Unlike biological viruses computer viruses don't have a shelf-life measured by their lifespan. It is measured in how long binary compatibility is maintained. It is foolish to think, "Gee, that wave has passed, we can all stop scanning now" is a sensible option.
-- Steve C. Lamb | I'm your priest, I'm your shrink, I'm your PGP Key: 8B6E99C5 | main connection to the switchboard of souls. -------------------------------+---------------------------------------------
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