CHAMPUS

chancre The classic nonpainful ulcer of syphilis that teems with spirochetes. A chancre forms in the first (primary) stage of syphilis, is highly contagious, and can last from 1 to 5 weeks. Syphilis can be transmitted from any contact with a chancre. If a chancre is outside the vagina or on the scrotum of the male, the use of condoms may not help in preventing transmission of syphilis. Likewise, if a chancre is in the mouth, merely kissing an infected individual can spread syphilis. See also syphilis.