According to reports from Bulgaria, the author of this virus is the same as the one who wrote the Nina virus, and inside the 1600 virus the following message can be found:
Dear Nina, you make me write this virus; Happy new year!
It should not come as a surprise that the author's girlfriend is named Nina.
The 1600 virus infects .EXE and .COM files, increasing their length by 1600 bytes, but COMMAND.COM is overwritten. At least some versions of COMMAND.COM will not work if infected, and infected COMMAND.COM files should be replaced, not disinfected.