Types of STD


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What is Syphilis?

Syphilis is a sexually transmitted infection (STI) caused by the bacteria Treponema pallidum. Syphilis is relatively common in Indonesia. Some people are at high risk of infection, including men who have sex with men and people who have unprotected sex. Syphilis is usually spread through sex with an infected person. Infection with syphilis initially causes a shallow painless ulcer on the genitals. If undetected and untreated syphilis can cause serious illness later in life, making screening and treatment really important! Syphilis can be detected with a blood test and treated effectively with antibiotics.


Syphilis infection is usually spread through direct contact with an infectious lesion. Early syphilis infection causes a shallow ulcer on the skin and contact with this lesion, typically during sex, can result in infection. Unprotected oral, anal or vaginal sex with a person with syphilis can all result in transmission of infection. However, the bacteria that causes syphilis cannot survive outside the body so it can’t be transmitted by touching objects someone with syphilis infection had touched or just being in the same room as someone with syphilis. Syphilis can also be spread through blood transfusion and sharing drug injecting equipment, although this is much less common cause of infection.

Syphilis infection can also spread from mother to baby. The bacteria that causes syphilis can cross the placenta, so if someone pregnant becomes infected, their baby can be infected before birth, or during birth. If a baby is exposed to syphilis while still inside the mother's womb they can get congenital syphilis. Congenital syphilis is a very serious disease as almost half of children congenital syphilis die shortly before or after birth. Even if they survive, they would experience significant morbidity throughout their childhood.

Syphilis infection and complications

Syphilis infection has four stages, each with different symptoms, which usually occur in this order:

  • Primary syphilis
  • Secondary syphilis
  • Latent syphilis
  • Tertiary or late stage syphilis

Primary syphilis

Primary syphilis is the first stage of infection, it can occur 2-3 weeks after becoming infected. Usually primary syphilis causes a red lump where the infection entered the body. The lump turns into a small sore or ulcer. These ulcers are commonly on or around the penis, vagina or anus, but can be in the back of the throat as well. Usually the ulcers don’t cause any pain and heal on their own, so often people don’t seek any treatment for them. If untreated the bacteria in the lesion can enter the blood and cause secondary infection.

Secondary syphilis

The second stage of syphilis occurs in around 25% of people not treated for primary syphilis. It begins a few weeks to months after primary syphilis.

Symptoms of secondary syphilis include:

  • Rash
  • Smooth, painless white wart-like lesions appearing in moist regions like the genitals, anal region and armpits called condyloma lata. These lesions are commonly mistaken as HPV (human papilloma virus) infection.
  • Fever
  • Flu-like symptoms including sore throat and muscle aches
  • Weight loss
  • Swollen lymph nodes

If untreated skin lesions resolve in weeks to months.

Latent syphilis 

In this stage of syphilis there are no symptoms, and infection can remain in the body for many years without anyone knowing or showing signs of infection. Latent syphilis can only be detected with specialised blood tests.

Tertiary syphilis

This stage of syphilis infection can cause serious damage to the heart, skin, brain and other organs. In some cases of latent syphilis the immune system reacts to the bacteria that has been dormant in the body which can cause very serious disease, including neurosyphilis.

Neurosyphilis is the name for syphilis infection that as moved into the brain or spinal cord. It can happen in primary, secondary, latent or tertiary syphilis. It can cause many symptoms including:

  • Headache
  • Confusion
  • Nausea and vomiting
  • Vision loss


Syphilis can be diagnosed by simple tests. More than 5 million cases of syphilis are diagnosed every year, with the majority occurring in low and middle-income countries, like Indonesia. Testing for syphilis involves either taking a swab of suspected ulcer or having a blood test.

If you are worried you might have syphilis or have a sexual partner that has been diagnosed with syphilis, you should see a doctor even if you have no symptoms!

If you see a doctor to get tested for syphilis they might test for other STIs to keep you safe and healthy. If you’re having unprotected sex regularly, regular testing is a great idea. To learn more about STI testing check out our testing article!


Syphilis infection can be cured by treatment with antibiotics. Primary and secondary syphilis can be treated with a single injection of antibiotics. Some latent and all tertiary syphilis infections require longer treatment but are still curable.

If you are treated for syphilis your recent sexual partners also need antibiotic treatment too. After finishing treatment most people need follow-up testing to make sure they are cured, this involves having another blood test a few months later.


Syphilis can only be transmitted by contact with people who have a syphilis infection. The risk of syphilis infection can be reduced by always using condoms during sex, avoiding sex if your partner has any symptoms that could be caused by an infection, or abstinence. If you’re worried you may have syphilis, it is safest to avoid any sexual intercourse and see your doctor as soon as possible!


Centers for Disease Control and Prevention (CDC) (2016, February 03). Syphilis - Images. Retrieved February 04, 2019, from https://www.cdc.gov/std/syphilis/images.htm

Chandrasekar, P. H. Syphilis (2017, July 11). Retrieved February 3, 2019, from https://emedicine.medscape.com/article/229461-overview

Hook, E. W. (2017). Syphilis. The Lancet, 389(10078), 1550-1557. doi:10.1016/s0140-6736(16)32411-4

Medical Encyclopedia. (2019, January 02). Retrieved February 02, 2019, from https://medlineplus.gov/encyclopedia.html

Osmosis. Treponema pallidum (Syphilis). (2018, January 13). Retrieved February 04, 2019, from https://www.osmosis.org/learn/Treponema_pallidum_(Syphilis)