ditto to what kim said.
it is all caused by the herpes virus (which has many variations)... when your immune system is down they tend to appear, which is why they are referred to as "cold sores". it is in fact not at all linked to cold/flu, they simply tend to appear more when the immune system is at a low point... herpes is also HIGHLY contagious, and not curable. avoid ANY contact- kissing, eating off of the same utensils, sharing drinks/bottles/cups, sharing chapstick, or ANY oral sexual encounter (yes, you CAN spread the infection to the genital areas- as well as nipples, even your eyes! it is all comprised of the same tissue, and can be affected by the virus). sunburns, or irritation from perfumes/defoliants can also trigger an outbreak. i lived with my ex for 7 years, and never contracted the virus, because i am completely OCD about cleanliness... wouldn't even share a cup when he didn't have an outbreak!
at 11:40 AM on Dec. 3, 2009