Transmission, symptoms and screening for syphilis

Syphilis is a sexually transmitted infection (STI) caused by the bacterium Treponema pallidum. People can contract syphilis more than once in their lifetime.

How is syphilis transmitted? Syphilis is contracted during unprotected sex (oral, genital or anal) when there is contact with a contagious lesion or rash. An infected woman can pass it on to her baby during pregnancy or childbirth.

People with syphilis do not always realize that they have symptoms of the infection and may therefore be infected or transmit the infection without knowing it. The first symptoms appear 10 days to 3 months after exposure.

Primary stage (10 to 90 days)

• Swelling or inflammation of the lymph nodes (can take from 1 to 6 weeks to disappear)
• Appearance of painless ulcers called canker sores on or around the mouth, genitals or anus, that disappears in 3 to 8 weeks
• Possibility of transmitting the infection to others even after the cankers have disappeared

Secondary stage (2 to 12 weeks, sometimes up to 6 months)

• Non-itchy rash on the palms of hands, soles of feet or the entire body
• Flu-like symptoms
• Hair loss

Latent stage

• No symptoms or reappearance of contagious lesions, but possibility of transmitting the infection to others
• Latency that can last from 20 to 30 years
• Untreated infection progresses to the tertiary stage in almost one-third of cases

Tertiary stage

• Hematological diseases
• Heart problems
• Skin, bone and joint damage
• Neurological problems

• Blood tests to detect any antibodies against the bacteria treponema pallidum (TP-PA, INNO-LIA) or associated with the presence of the bacteria (RPR, formerly VDRL).

Syphilis is treated with antibiotics, mainly penicillin administered via intramuscular injection. Treatment is generally effective for primary and secondary infections. However, damage caused by tertiary-stage syphilis can be permanent, so infected people should seek treatment as soon as possible to avoid complications which may include damage to the heart, brain, bones and liver.

Syphilis also increases the risk of contracting or transmitting HIV.