How can syphilis be transmitted?

Transmission occurs when skin or mucous membranes contact an infectious syphilis sore or lesion. This can happen during vaginal, anal, or oral sex, and can also occur through kissing when an infectious sore is in or around the mouth. Sores may be painless and may heal without treatment, while the infection continues.

A pregnant person with syphilis can pass the infection to the developing baby during pregnancy. Syphilis is not spread by toilet seats, swimming pools, casual household contact, or sharing ordinary utensils. Because symptoms may be absent, a person cannot reliably judge transmission risk by looking for a sore.

Arrange STI screening after a possible exposure and give the clinician the date, type of contact, and any symptoms. Testing may need to be repeated when exposure was recent. Avoid sexual contact that could expose another person while awaiting advice, and do not share medication.

If syphilis is diagnosed, take the recommended antibiotic treatment and attend follow-up. Recent partners may need confidential testing or treatment. During pregnancy, contact maternity or sexual-health services promptly so assessment and treatment can be coordinated.

Seek prompt medical care for a known exposure, a painless genital or mouth sore, an unexplained rash, swollen glands, or a positive test. Seek urgent help for vision changes, severe headache, confusion, weakness, hearing changes, or problems with balance. Pregnancy with a possible exposure or symptoms requires timely assessment.

Ask which exposures matter most, whether testing should happen now or be repeated, whether you need tests for other infections, how to protect partners, what treatment involves, and which symptoms require urgent care.