Viruses come in all types and target different area. The one thing they share is this: the faster you get rid of them, the less damage they cause.
Businesses are especially vulnerable to threats from viruses because of downtime and legal and ethical implications from viruses stealing confidential information.
Individuals can suffer from identity theft after a virus/cyber attack.
There is no full-proof way to eliminate the threat viruses and spyware pose, but the best solution is a good anti-virus software and regular cross-checks.