Background  Herpes is a prevalent, infectious disease that can occur anywhere on the body; it is found primarily on the face and genitalia. Herpes simplex virus type 1 (HSV-1) and herpes simplex virus type 2 (HSV-2) are the DNA viruses that cause human herpes. Clinically, HSV-1 and HSV-2 infections produce lesions generally located on the mucocutaneous junctions of the face and genitalia. At times, vesicular lesions may ulcerate, leaving recalcitrant wounds that are challenging to treat. Until now, the basis of treatment has been related to the eradication of the viral infection. Little attention has focused on the consequence of the viral infection and the resulting wounds, specifically whether this represents an epidermal or dermal injury.

Methods  Using 10 herpetic lesions from different individuals, we studied the depth of the injury via routine hematoxylin and eosin stains, as well as periodic acid–Schiff (PAS) and type IV collagen stains, which demonstrate the presence of the basement membrane.

Results  In all cases, we found an inflammatory infiltrate in the dermis and selective disruption of the basement membrane.

Conclusion  This suggests that herpetic lesions involve the dermis and are best classified as partial-thickness wounds.