The endurance specs are 20GB a day for 5 years. Intel specs are, it seems, a bit conservative. Here is a 40GB 320 drive with 314 Terabytes on it and it's still going strong. Bottom line; don't worry.
at the slight hint of a virus attack (about once a month) I recover my OS drive from the last image
In all the years since I built my first computer in 1976 (an IMSAI 8080) I can count on two fingers the number of times I've had to deal with a "virus attack". And honestly I think it was only once!
I'd want to focus on what is causing the once-a-month corruption and fend those off completely. I haven't run any anti-virus software for many years, but recently I like COMODO Internet Security Premium (free av, firewall, and malware protection).