Editor-In-Chief: C. Michael Gibson, M.S., M.D. ;Associate Editor(s)-in-Chief: Kiran Singh, M.D. 
Eczema herpeticum is a disseminated herpes infection generally at sites of epidermal disruption such as atopic dermatitis, burns, eczema etc... The causative organism is herpes simplex virus type 1 or 2.
Eczema herpeticum results in a severe disseminated infection, involving multiple organs - eyes, brain, lung, liver and others and can be fatal. Treatment with systemic antiviral drugs, such as acyclovir or valaciclovir, is therefore needed.
When smallpox vaccination was still being routinely administered, the vaccinia virus used in the smallpox vaccine could cause a similar syndrome if the patient had an active eczema. This condition is called eczema vaccinatum. Eczema herpeticum and eczema vaccinatum are collectively known as Kaposi's varicelliform eruption.