More about Conficker Worm

Users can protect themselves from the worm by installing Microsoft's MS08-067 security update, using strong passwords and disabling Windows' Autoplay and Autorun features.
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Conficker B++?

"From late November through December 2008 we recorded more than 13,000 Conficker infections within our honeynet, and surveyed more than 1.5 million infected IP addresses from 206 countries. More recently, our cumulative census of Conficker.A indicates that it has affected more than 4.7 million IP addresses, while its successor, Conficker.B, has affected 6.7M IP addresses"

Read more on SRI's Analysis Report