Though it achieved fame because it was the first of its type, the virus was not widespread as it could only travel by hitching a ride on floppy disks swapped between users.More details over here.
Now 20 years after they first appeared there are more than 150,000 malicious programs in existence.
Computer virus is now 20 years old

BBC reports PC viruses are now more than 20 years old. The first computer virus appeared somewhere in the first weeks of 1986 and was called Brian.