How is syphilis primarily transmitted?

Syphilis is primarily transmitted through contact with a syphilis sore during sexual activity, which can include vaginal, anal, or oral sex. The bacteria responsible for syphilis, Treponema pallidum, can be present in the sores, and exposure to infected bodily fluids, such as blood or semen, increases the risk of transmission.

While contact with bodily fluids is the primary mode of transmission, it’s important to note that the disease can also be transmitted from an infected mother to her baby during pregnancy or childbirth. This can occur even if the mother does not have visible sores.

Other transmission routes are less relevant in the context of syphilis. Inhalation would imply respiratory transmission, which is not applicable for this sexually transmitted infection. Vector-borne transmission typically involves insects or parasites, which does not pertain to syphilis. Fecal-oral transmission is associated with gastrointestinal pathogens, and there's no link to syphilis transmission through this route.

Thus, the correct choice regarding the primary transmission of syphilis is through contact with infected bodily fluids, including those mentioned.