These are not dangerous memory resident parasitic viruses. They hook INT 21h and write themselves to the beginning of .COM files that are executed. They contain the text strings:
This Remark is used as an identification
pattern for the Anti-Virus-Utility.
Do not try to change it.
This Remark is used by the anti-virus utility as a pointer
to the end of the Virus.
"Smvb.1023" also hooks INT 8 to prevent debugging. "Smvb.1100" hooks INT 16h and tries to change the keys that are entered, but fails. "Smvb.708" hooks INT 17h and changes the symbols that are printed.
