The United States Immunodeficiency Network (USIDNET) was funded by a cooperative agreement, U24AI086037, from the National Institute of Allergy and Infectious Diseases (NIAID) and the National Institutes of Health (NIH), awarded to the Immune Deficiency Foundation (IDF). NIAID supports basic and applied research to better understand, treat and ultimately prevent infectious, immunologic, and allergic diseases. We also thank our partners from Industry, Foundations and philanthropy for continued and generous support.