There has almost always been malware for the Mac. Malwarebytes strives to proactively detect and block all Mac malware, providing additional protection against the worst threats that exist on the Mac. New version 3.0 includes real-time protection, rather than requiring manual scans in Mac OS X. The first widespread virus was the Elk Cloner virus, which actually infected the Apple II, prior to any PC malware. Some of the earliest malware affected the first Macs in the mid-1980s. It didnt take long for more to start appearing.”]
Source: https://blog.malwarebytes.com/malwarebytes-news/2017/08/solution-corner-malwarebytes-mac/