Clean Virus - Virus Cleaner

The best anti-virus software for the Mac:
Symantec Norton AntiVirus
Scanning test Mac roughly 410,000 files (give or take a GIF here and there) had little to no impact on performance. Surfing the Web, checking e-mail, and listening to music with iTunes were as snappy as I’d expect on my 2.16GHz Core Duo MacBook Pro.
NAV took [...]

Some recommendations on replacing Mcafee:
Try NOD32 Antivirus Enterprise Edition. It is often the highest rated antivirus solution in online tests. The software is unobtrusive and small, unlike many other solutions. It is also very well priced per node. Everything can be centrally managed, many tasks can be automated, and it has nice reporting tools.