Bacterial

Syphilis

Transmitted via direct contact with a sore — condoms only protect if they cover it.

Cause

Bacterium (T. pallidum)

Asymptomatic

Often in early stages

Curable

Yes — penicillin

Vaccine

Overview

Syphilis is caused by Treponema pallidum and progresses through distinct stages. The primary infection produces a painless ulcer (chancre) at the site of exposure that heals on its own, giving a false sense of recovery. Without treatment, the infection advances through secondary and latent stages and can eventually cause severe organ damage. Syphilis rates have risen significantly across Europe and North America since 2010.

How it spreads

Direct contact with a sore (chancre) during vaginal, anal, or oral sex
The sore may be hidden inside the vagina, rectum, or under the foreskin
Condoms reduce risk only if they fully cover the sore
Mother to fetus during pregnancy (congenital syphilis)

Symptoms

Stage 1: A single, painless sore (chancre) at the infection site — often unnoticed
Stage 2: Rash on palms and soles, flu-like symptoms, mouth sores
Latent: No symptoms — can last years
Stage 3 (tertiary): Serious damage to heart, brain, and other organs

The primary chancre is painless and often hidden, making early detection difficult. The secondary rash can be mild and easily mistaken for other conditions. Many people are diagnosed incidentally via routine sexual health screening.

Vaccine

No vaccine is currently available for Syphilis.

Treatment

Syphilis is curable at all stages with penicillin (benzathine penicillin G). Early stages require a single injection; later stages need longer treatment. Doxycycline is used for people allergic to penicillin. Treated early, syphilis causes no lasting damage.

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Educational purposes only. Consult a healthcare provider for personal medical advice.