Some simple steps can be taken to protect data integrity and security:
-Don't leave the data connected to the Internet 24/7.
-Power off the storage medium when you are done with it.
-Keep it in a physically safe location when not in use.
-Encrypt the data or the volume.
-Have a backup of your backup on a different medium and if possible different location.
-Don't advertise the data.
These are activities which are easy to set up and can help insure a more pleasant digital lifestyle. You could go to more extremes but then it becomes invasive. Not worrying about it much because you find it unlikely or just don't care is bad. Not worrying about it much is what you want to do because you have taken the important but easy steps to keep yourself safe.