Acronis Blog – 6.24.22
Antivirus software has been around for many years. In fact, the first antivirus software dates back to 1971, when a virus known as the Creeper infected and spread to PDP-10 mainframe computers manufactured by Digital Equipment Corporation (DEC). To combat the Creeper, an American computer programmer developed the Reaper. It was a program designed to delete the virus, but was, in fact, a virus itself.
Source: Do I need computer antivirus software? – Definition & Use Case