Leprosy is caused by the organism Mycobacterium leprae. The leprosy test involves injection of an antigen just under the skin to determine if your body has a current or recent leprosy infection. The injection site is labeled and examined 3 days and 28 days later to see if there is a reaction.
Update Date 9/10/2015
Updated by: Jatin M. Vyas, MD, PhD, Assistant Professor in Medicine, Harvard Medical School; Assistant in Medicine, Division of Infectious Disease, Department of Medicine, Massachusetts General Hospital, Boston, MA. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.