Computer and laptop viruses, seem to be proliferating faster than the diseases they were named after and like the organic varieties the instigators and malicious coders who design these programs are making them harder to detect and they are also coming up with new delivery methods.
These malicious programs, which probably started life as playful code, have evolved into rather potent tools capable of making even the most advanced IT infrastructure hidden behind hardware firewalls grind to a halt.
This is the main reason why you should always keep your antivirus software up to date. Last month’s or even last week’s virus definition data base will not be enough to protect you from the latest incarnation of even an older virus
Unfortunately though to really secure your home or business pc from infestation and to reduce the vulnerability of your system, it is advisable that you also make sure you have other software installed that can detect malware, for example Malwarebytes (a free download), as the effects of this can be as if not more devastating than a simple virus, and can in certain circumstances leave your PC open to hacking or even digital theft and identity theft.Fortunately, there are companies like LifeLock.com that can help you protect your identity if your PC gets hacked.
If you do keep passwords and sensitive documents on your computer you could always password protect the files using standard functionality that is built into office software.