Anthrax produced by the bacterium Bacillus anthracis is the most serious biothreat facing the civilian and military populations of the United States. Anthrax spores are a leading bioweapon due to their stability and ease of dispersal. Inhalation anthrax presents with non-specific symptoms that cannot be distinguished from many more common respiratory diseases. Mortality rates approach 100% if untreated. Lower mortality rates occur when timely and appropriate antibiotics are administered. The key is early diagnosis.

Currently, diagnosis of anthrax is based on the standard blood culture. Microbiological diagnosis requires 24-48 h from the time that a sample of blood is taken from a patient. This is too late for effective treatment.

Research by our laboratory aims to produce a test that can identify individuals with early stage anthrax in 5-10 min. This is a mature project that detects the capsular antigen of Bacillus anthracis that is shed into blood during infection. Monoclonal antibodies to the capsular antigen have been produced, and immunoassays using the ELISA and lateral flow immunoassay formats have been developed.

Initial studies in mice and monkeys by the our laboratory and collaborators found that assays of blood for capsular antigen are positive at or before the time that a blood culture is positive. As a consequence, there is convincing proof-of-concept for use of an immunoassay for capsular antigen for rapid diagnosis of anthrax.

Project investigators: This project is a collaboration between UNR [Thomas Kozel, Ph.D. (Principal Investigator) and David AuCoin, Ph.D. (Co-Investigator) and InBios International (Seattle, WA), a medical diagnostic company that specializes in developing and marketing diagnostic tests for the detection of infectious diseases.

Grant support: This study is supported by NIH grant NIH/NIAID R01 AI093365, Immunoassay for capsular antigen for rapid diagnosis of anthrax, 2011-2018, and Department of Homeland Security HSHQDC-15-C-B0067, Immunoassay for diagnosis of anthrax, melioidosis, glanders and Ebola, 2015-2018.