Of all infections, this is the type an administrator should be most worried about. Its rare, but exceptionally damaging. Most A/V tools aren't going to catch it, so unless you are monitoring all IP activity from your computer and doing offline filesystem checks, a virus like this could compromise your systems for years.

Usually something this sophisticated is used to target specific individuals/organizations as they aren't generic botnet/bitcoin mining operations.

They might be after specific info and after they get it, they might even wipe their tracks as it's better to have a tool that nobody knows to look for than one that can get on as many computers as possible.