Last year they released the Avast antivirus for mac which is in beta till now, if you are thinking antivirus for mac? What is the need? So the story is same that virus is a software written by someone to work in a malicious way. Now it depends upon the intention of a coder if one codes for a good purpose or for a bad one but we shouldnt forget our purpose to protect the operating system. There are many paid antiviruses in the market for Windows as well as for Macintosh so obviously there are viruses for Mac which resulted in antiviruses for the same, so you should not be in any confusion that Macs are immune to viruses. Still its not a bad deal to install something for security which is absolutely free that too from a famous vendor.You can download and install the Avast AV for your mac from the link below
Last year before the release of Avast security for Mac I also posted about Sophos Antivirus For Macintosh here that also many people use. So now you have two choices either Sophos or Avast depending upon if you need a free security for your Macintosh or a paid one which would be for sure a better solution like Kaspersky, Norton and Others. Avast`s version for Macintosh is in beta now and once it will be released as a final version, I can straight away recommend it for Windows as well as Macintosh. If you use a different security product to protect your Apple machine, do let us know which one and why you think its a better one than any other.