This virus was written in Iceland and first discovered there in October 1989. It contains the following text strings:
GhostBalls, Product of Iceland Copyright (c) 1989, 4418 and 5F19
Allow F-Secure Anti-Virus to disinfect the relevant files.
For more general information on disinfection, please see Removal Instructions.
Basically it is just the Vienna virus - the variant in the book by Ralf Burger to be specific, with an extra twist. When an infected program is run, the virus will search for other programs to infect, but also try to place a modified copy of the Ping-Pong virus on the diskette in drive A, provided it is a 360K diskette. This Ping-Pong variant has been changed, so that it is not infectious, but it will also work on a '286 machine.