No, it wouldn't.cignus_pfaccari said:A DC 12 disease would likely stack commoners up like cordwood, given their lack of any real Fort save and all (when Con = 10 and HD = 3, that's a +1!).
A DC 12 save with a +1 save means there's a 50% chance / day she'll take attribute damage.
Once the commoner realizes she caught a disease, she'll stay in bed, so she'll regain two points of attribute damage per day.
If the disease isn't overcome after a couple of days, a healer will look after her so she'll regain 2 or 4 points of attribute damage per day (depending on how good the healer is) and gets to use the healer's heal check instead of her saving throw.
It's important to remember she's regaining those points even if she takes attribute damage for that day.
For a disease dealing d4 damage, that's an average loss of 1.25 per day. For 1d6 damage it would be 1.75 per day. So, in both cases simple bed rest will on average heal more damage than she takes from the disease. Even without access to a healer she should survive it quite easily.