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Can syphilis spread through direct nonsexual contact?

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Scanning electron micrograph of Treponema pallidum, the spirochete bacterium that is the causative agent of syphilis. — syphilis Scanning electron micrograph of *Treponema pallidum*, the spirochete bacterium that is the causative agent of syphilis.

While syphilis is primarily a sexually transmitted disease, it can occasionally be acquired through direct nonsexual contact with an infected person.1

Transmission via nonsexual contact typically occurs through direct interaction with active syphilis sores, known as chancres, which contain the causative bacterium, Treponema pallidum. For instance, the infection can be transferred through kissing if there is direct contact with an active sore in the mouth. During the primary and secondary stages of the disease, the infection can be easily passed to others who come into contact with these open lesions.123

Additionally, a related group of infections known as nonvenereal syphilis—which includes yaws, bejel, and pinta—is spread specifically through direct, nonsexual contact, often among children and young adults in regions with crowded conditions and limited health care.13