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HealthInfo Canterbury


What is syphilis?

Syphilis is a sexually transmitted infection caused by a bacteria (bug) called treponema pallidum. This bacteria enters the body through tiny breaks in the skin, mainly in the anal area, genital area, or the mouth.


There has been a sudden increase in syphilis in New Zealand in the last few years. Initially it was mostly seen in homosexual men but is now occurring in heterosexual men and women. It is very important to get checked out if you have any new genital sores or if you think you may be at risk.

How do you get syphilis?

Syphilis is very infectious and is caught by having sexual contact with an infected person. This may include vaginal, anal, or oral sex, or just close skin-to-skin contact.

Syphilis can also be spread from mother to baby during pregnancy, if the mother is infected.

How do I know if I have syphilis?

Many people do not get any symptoms and would not know they have syphilis without having a blood test.

It can take up to three months to develop antibodies so the tests may be negative early on.

For those who get symptoms, syphilis is divided into three stages: primary, secondary, and tertiary. Primary and secondary syphilis is infectious, but tertiary syphilis is not.

Primary syphilis


Any genital sore should be examined by a doctor, even if it starts to heal and is small and painless.

Secondary syphilis


A person in the primary or secondary stage of syphilis is very infectious because the sores and rashes are full of syphilis bacteria. There is a very high chance of infecting a sexual partner.

Tertiary syphilis

In about a third of people, if not treated, the syphilis bacteria will eventually cause damage to the heart, brain, and the nerves. Treatment is to prevent further damage. Tertiary syphilis is not infectious. You can avoid tertiary syphilis by getting treatment early.

How is syphilis treated?

Does syphilis affect pregnancy?

Depending on how long a pregnant woman has been infected, she has a good chance of passing the infection to her unborn baby. This could result in a stillbirth or miscarriage.

An infected baby may be born without symptoms of syphilis, but could develop them within a few weeks and the baby could become very ill. However, proper treatment of the mother during pregnancy will prevent the baby being born with syphilis.


Every woman should have a blood test for syphilis during her pregnancy.

What is the link between syphilis and HIV?

It is now known that the genital ulcers caused by syphilis also make it easier to transmit and acquire HIV infection sexually. There is a two to five times greater risk of catching HIV infection when syphilis is present.

Talking to partners

If you have been diagnosed with syphilis, it's important that all your sexual partners from the last few months and sometimes longer, and attend a sexual health clinic for testing and treatment, if necessary. If you have had sex with someone while the sore or rash was present, that person will usually need treatment.

Some people feel embarrassed, scared, or angry when they or their partner have a sexually transmitted infection (STI). This is common and OK. Do not let these feelings stop you from getting medical help or telling your partner. Anyone who is sexually active can get an STI.

What do I do?

How do I protect myself from syphilis?

The only sure way to avoid getting syphilis or another sexually transmitted infection is to not have sexual contact. If you do decide to have sexual contact, you can reduce your risk by:

Where do I go for a check-up?

Sexual health clinics have specialists who are experienced in the management and diagnosis of syphilis. Treatment is free and confidential and the people there can help with testing your sexual partners or family members. Read more about the Sexual Health Clinic.

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Written by Christchurch Sexual Health Centre and Auckland Sexual Health Service. Last reviewed September 2016.

Page reference: 53679

Review key: HISYP-53679