(The Best Years in Life) Cold sores, also called fever blisters, are common viral infections caused by a herpes simplex virus (HSV-1) closely related to the one that causes genital herpes (HSV-2), They are tiny, fluid-filled blisters on and around your lips which may appear singly or may be grouped together in patches. After the blisters break, a crust forms over the resulting sore. Cold sores usually heal in two to four weeks without leaving a scar. Although there are no known outright cures, at least not in mainstream medicine, for the recurrence of cold sores, there are natural ways to help them heal quickly as well as help prevent their return - and you just might be able to cure them entirely. Read More.