Skip directly to site content Skip directly to page options Skip directly to A-Z link Skip directly to A-Z link Skip directly to A-Z link
Volume 8, Number 10—October 2002
Bioterrorism-related Anthrax
Bioterrorism-related Anthrax

Specific, Sensitive, and Quantitative Enzyme-Linked Immunosorbent Assay for Human Immunoglobulin G Antibodies to Anthrax Toxin Protective Antigen

Conrad P. Quinn*Comments to Author , Vera A. Semenova*, Cheryl M. Elie*, Sandra Romero-Steiner*, Carolyn M. Greene*, Han Li*, Karen Stamey*, Evelene Steward-Clark*, Daniel S. Schmidt*, Elizabeth Mothershed*, Janet Pruckler*, Stephanie Schwartz*, Robert F. Benson*, Leta O. Helsel*, Patricia F. Holder*, Scott E. Johnson*, Molly Kellum*, Trudy Messmer*, W. Lanier Thacker*, Lilah Besser*, Brian D. Plikaytis*, Thomas H. Taylor*, Alison E. Freeman*, Kelly J. Wallace*, Peter Dull*, Jim Sejvar*, Erica Bruce*, Rosa Moreno*, Anne Schuchat*, Jairam R. Lingappa*, Sandra K. Martin*, John Walls*, Melinda Bronsdon*, George M. Carlone*, Mary Bajani-Ari*, David A. Ashford*, David S. Stephens*†, and Bradley A. Perkins*
Author affiliations: *Centers for Disease Control and Prevention, Atlanta, Georgia, USA; †Emory University, Atlanta, Georgia, USA;

Main Article


Calculation of diagnostic sensitivity and diagnostic specificity by using cohorts of known vaccination or infection statusa

          Serum test group           AVA vaccinees           Non-Vaccinees           NHANES controls           Non-anthrax infections           Clinical anthrax serab           Total sera of known infection and vaccination status
          True positivesc           67           0           0           0           15           87
          True negativesd           0           15           228           260           0           503
          False positivese           0           4           10           17           0           31
          False negativesf           1           0           0           0           1           2
          Total           68           19           238           277           16           618
          Diagnostic specificity           n/a           78.9%           95.7%           93.8%           n/a           94.2%
          Diagnostic sensitivity           98.5%           n/a           n/a           n/a           93.7%           97.6%

aAVA, anthrax vaccine adsorbed; NHANES, National Health and Nutrition Examination Survey; n/a, not applicable.
bClinical anthrax sera were obtained from donors that met the Centers for Disease Control and Prevention case definition for confirmed cutaneous and inhalational anthrax. Patients were classified as either reactive or nonreactive.
cSera are considered true positives if they were obtained from clinically confirmed anthrax cases or from donors with a documented history of anthrax vaccination.
dTrue-negative sera were selected on the basis of having no known exposure to Bacillus anthracis infection and no known anthrax vaccination.
eFalse-positive sera are defined as sera which reacted (>3.0 µg/mL) in the anti-protective antigen immunoglobulin G enzyme-linked immunosorbent assay but for which there is no history of clinical anthrax or anthrax vaccination.
fFalse-negative sera are defined as sera from donors who are documented as vaccine recipients or had clinically confirmed anthrax.

Main Article

Page created: July 19, 2010
Page updated: July 19, 2010
Page reviewed: July 19, 2010
The conclusions, findings, and opinions expressed by authors contributing to this journal do not necessarily reflect the official position of the U.S. Department of Health and Human Services, the Public Health Service, the Centers for Disease Control and Prevention, or the authors' affiliated institutions. Use of trade names is for identification only and does not imply endorsement by any of the groups named above.