Technically a form of herpes, cold sores are lesions which typically appear around the nostrils and lips. The term “cold sore” is something of a misnomer, as the lesions are not caused by infection with the cold virus. Rather, a cold, flu or fever can trigger the reactivation of the latent herpes zoster virus, which remains in the body for life once contracted. It is estimated that up to 90 percent of the adult population of the United States will be infected with the Type 1 herpes zoster virus by the age of 50, making the occurrence of cold sores very common. Treatment is aimed at reducing the pain and swelling associated with the lesions, but there is no way to outright cure them.