Primary Syphilis

Primary syphilis is typically acquired via direct sexual contact with the infectious lesions of a person with syphilis.  Approximately 10–90 days after the initial exposure (average 21 days) a skin lesion appears at the point of contact, which is usually the genitalia, but can be anywhere on the body. This lesion, called a chancre, is a firm, painless skin ulceration localized at the point of initial exposure to the spirochete, often on the penis, vagina  or rectum. In rare circumstances, there may be multiple lesions present, although it is typical that only one lesion is seen. The lesion may persist for 4 to 6 weeks and usually heals spontaneously. Local lymph node swelling can occur. During the initial incubation period, individuals are otherwise asymptomatic. As a result, many patients do not seek medical care immediately.

Primary chancre  of syphilis on the hand. Unlike some kinds of sexually transmitted infections, syphilis infections are not limited to the genitals, and can be transmitted through non-sexual contact.