Syphilis testing and prevention

Last updated May 14, 2024


Who should be tested for syphilis?

Anyone who is sexually active can get syphilis, but some people have an increased risk of acquiring syphilis. Your risk of syphilis may be higher if you:

  • Are gay, bisexual or another man who has sex with men (MSM).
  • Have unprotected sex, especially if you have several partners.
  • Are living with HIV.
  • Have had sex with someone who has tested positive for syphilis.
  • Tested positive for another STI, such as chlamydia, gonorrhea, or herpes.

A person who is pregnant and has syphilis can pass the infection in utero to their baby. Those who are pregnant should get tested for syphilis during their first trimester, third trimester, and at delivery. The infection can cause death or severe health problems in babies and children, but these can be prevented if you get treatment quickly.

You should get tested if you or someone you have sex with has symptoms. If you think you have syphilis, get tested at your doctor’s office, local health department, community health clinic, or STI clinic. 

Simple blood tests can tell if you have syphilis. You can have syphilis without symptoms, so get tested to be sure.

STI testing isn’t always part of your regular checkup - you may have to ask for it. Be open and honest with your health care provider so they can help you figure out which tests are best for you. 

Find a syphilis test


How is syphilis diagnosed? 

You can’t tell if you have syphilis just by the way you feel. Like all STIs, the only way to know is to get tested.

Syphilis is sometimes called "the great imitator" because early symptoms are similar to those of many other infections. Sexually active people should talk with a doctor or other health care provider about any rash or sore in the genital area. Those who have been treated for another STI, such as gonorrhea, should be tested to be sure they do not also have syphilis.

There are three ways to diagnose syphilis:

  • Recognizing the signs and symptoms.
  • Examining blood samples.
  • Identifying syphilis bacteria under a microscope.

The doctor uses these approaches to diagnose syphilis and decide the stage of infection and appropriate treatment.

Blood tests also provide evidence of infection, although they may give false negative results (not show signs of an infection despite its presence) for up to three months after exposure. False positive tests (showing signs of an infection when it is not present) also can happen. Therefore, two blood tests are usually used. 


How can I protect myself and others from syphilis?

It is important that you advocate for your sexual health. Start with: 

  • Before you get intimate, talk with your partner about past partners and STI history. CDC provides conversation starters for the topic.
  • Create a safer sex strategy. Condoms, used correctly and every time you have sex, lower risk for all STIs.
  • Find a health care provider with whom you can have honest conversations.

  • Get tested—and retested as needed. For any STI, the earlier you catch it, the better your treatment options. 
  • Know the symptoms, but remember that symptoms can often go unnoticed.
  • Remember that you can get syphilis again even if you have previously been treated for it.
  • If you test positive, tell your partners and make sure they get tested. You can do this in person, anonymously, or by contacting your State Health Department for help.