The virus Killok.A was released in a virus magazine. It's one feature of interest was that the virus kept its infection code encrypted until it was needed. This makes the virus extremely obvious and unlikely to ever become a real threat.
Shortly after that the virus Killok.B was released. It was just a minor variation of the encrypted infection code idea. It contained the text:
'--------------------------------------\ REM a Virus from NoMercy!!! REM http://www.oocities.org/researchtriangle/3996 REM any critics, suggestions are welcome! REM Yogyakarta, May/15/1997 '-------------------------------------/The August 19 update of the PC-Cillin file called this virus Word_Kilo.B and the signature they picked for this virus was "://www.geociti"
The August 19 update was supposed to be only for the new PC-Cillin but Trend hasn't made this obvious so most users aren't updating to the new version.
This isn't the first time PC-Cillin has given false alarms like this. Before, it caused a false alarm for Word_BACALAH_1-Z, and before that, an alarm for Word.Generic.
Modern antivirus software uses a virus map so it looks for the virus only where the virus would hide and almost never gives false alarms. Other software also has a much higher detection rate. For just one example, see here.