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Syphilis causes and diagnosis

2-minute read

Syphilis can be contracted by a variety of different causes and is diagnosed with a blood test.

Causes of syphilis

Syphilis is usually spread through skin-to-skin contact during vaginal, anal, or oral sex. However it can also be spread by kissing or by direct contact with open sores on areas such as the lips, mouth, breasts, or genitals.

Syphilis is highly infectious during the time when a sore or rash is present. It can also be passed on before people know they have it and by people who don't have any sores.

Syphilis can occasionally be spread by blood contamination, via needle-stick injury or sharing injecting equipment. However it is extremely rare to get syphilis through a blood transfusion.

A pregnant woman with syphilis can pass the infection on to her baby via the placenta during pregnancy.

Syphilis diagnosis

Your doctor will need to do a blood test to confirm a diagnosis of syphilis. However, if your result is negative, you will need to be re-tested, because it can take three months to develop antibodies. Your doctor may also do a swab test from a sore. When syphilis is diagnosed your doctor will report it to the local health authorities.

Not sure what to do next?

If you are still concerned about syphilis, why not use healthdirect’s online Symptom Checker to get advice on when to seek medical attention.

The Symptom Checker guides you to the next appropriate healthcare steps, whether it’s self care, talking to a health professional, going to a hospital or calling triple zero (000).

Last reviewed: June 2017

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