The National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health (NIH), launched the Atopic Dermatitis and Vaccinia Network (ADVN), a nationwide research group that seeks to reduce the risk of eczema vaccinatum (EV), a severe and potentially deadly complication of smallpox immunization.

EV occurs almost exclusively in people with a history of atopic dermatitis (AD), a chronic, itchy skin condition commonly referred to as eczema. While uncommon, EV can develop when AD patients are given the smallpox vaccine or come into close personal contact with people who recently received the vaccine. If untreated, EV can kill between 1to 6 per cent of those affected. In children younger than 2 years of age, EV has been estimated to kill up to 30 per cent.

"Millions of Americans have a history of atopic dermatitis," says Anthony S. Fauci, M.D., director of NIAID. "Launching this network is an important step toward our goal of helping to protect everyone against the smallpox virus without the risk of life-threatening complications."

"Previous studies suggest that both innate and adaptive immunity are impaired in patients with atopic dermatitis, but the specific defects that increase the likelihood of eczema vaccinatum have yet to be explained," says Daniel Rotrosen, M.D., director of NIAID's Division of Allergy, Immunology and Transplantation. "The information generated by this network will improve our understanding of the immune responses of these patients and should greatly influence the design of a safer smallpox vaccine."

The ADVN comprises three integrated components: a clinical studies consortium, an animal studies consortium and a statistical and data coordinating center.

The ADVN Clinical Studies Consortium will, among other activities, seek to understand why people with AD have such severe reactions to smallpox vaccine by evaluating their immune responses after natural exposure to less harmful skin viruses such as herpes simplex. The ADVN Animal Studies Consortium will establish animal models of AD and investigate their immune responses to vaccinia - the virus used in smallpox vaccine - and other skin viruses such as varicella, which causes chickenpox and shingles. The ADVN Statistical and Data Coordinating Center will support these clinical and animal studies by analyzing research data, coordinating trials and regulatory activities, and developing and maintaining a registry of AD patients.