People with atopic dermatitis (AD), also known as eczema, experience hot, dry, scaly skin with severe itching. In addition, people with AD are prone to skin infections and inflammation. Little is known about the causes of AD. The purpose of this study is to create a registry of people both with and without AD. This registry will be used as a source of data to determine genetic markers for AD and also as a potential participant database for future studies.

AD is a chronic, inflammatory skin condition characterized by itching, flaking skin, and a tendency to acquire viral skin infections. The causes and complications of AD are not well understood. The purpose of this study is to establish a registry of people, both with AD and without AD, to help determine genetic markers of AD as well as to contact for participation in future AD studies.

This study will consist of one visit at which the participant's complete medical history will be taken, and blood collection may occur. Participants may be contacted at a later date to participate in future AD studies.

• Participants with AD who currently have or have had Eczema Herpeticum (EH)
• African Americans and Caucasians of non-Hispanic lineage with AD who do not have and have never had EH
• Participants with AD who currently have or have had Eczema Vaccinatum (EV)
• Participants with AD who do not have and have never had EV despite receipt of the smallpox vaccination
• Participants with AD and a currently active case of Molluscum Contagiosum (MC)
• Participants without AD but who currently have an active case of MC
• Healthy participants with currently active or history of AD, EH, EV, or MC

Inclusion Criteria:

• Meet criteria for one of the AD groups or for healthy volunteer status groups. More information on this criterion can be found in the protocol.
• Must be non-Hispanic, African American or Caucasian for participation in some groups. See information in Groups above for more information
• Residing in the United States
• Parent or legal guardian willing to provide informed consent, if applicable

Exclusion Criteria:

• Has atopy but lacks stringent AD features (only presumptive diagnosis of AD)
• History of any systemic illness other than AD
• Autoimmune or immunodeficiency disease
• Active systemic malignancy. Participants with uncomplicated non-melanoma skin cancer are not excluded.
• Any skin disease other than AD that might compromise the stratum corneum barrier (e.g., bullous disease, psoriasis, cutaneous T-cell lymphoma).
• Investigational research agents within 30 days prior to study entry