The natural history of recurrent oral-facial herpes simplex virus infection.

Oral-facial herpes simplex virus infection is a common, worldwide affliction on which neither public health procedures, vaccines, nor antiviral chemotherapy have yet to have a significant clinical impact. Careful examination of the pathogenesis and clinical features of this illness could lead to insights and a rationale for new and more effective preventive and therapeutic measures. The resistance of recurrent herpes simplex labialis to antiviral chemotherapy may be caused in part by inoculation of the skin simultaneously at multiple foci, such that only a few cycles of virus replication are needed before there is coalescence of the foci, destruction of the epidermis, and clinical lesion formation. Studies of herpes simplex labialis induced by ultraviolet radiation have suggested that there is a subpopulation of lesions that develop immediately after irradiation and that are refractory to chemotherapy. The difficulty finding a treatment for herpes simplex labialis may in part be methodological. Clinical trial protocols for antiviral drugs should target susceptible lesion subgroups and specific stages of the disease.