How Does Syphilis Testing Work?

If you’ve never been tested for syphilis, the process might seem confusing.

This guide walks you through everything you need to know about how syphilis testing works—from the type of sample collected to how labs analyze it and what your results mean.

What kind of sample is collected?

Unlike some other STD tests, syphilis testing doesn’t involve swabs or urine samples. It starts with a simple blood draw—just one small tube taken from your arm.

That blood sample is then used to run one or more types of lab tests, depending on your provider and the lab’s standard procedures.

What tests are used to detect syphilis?

Syphilis is usually diagnosed using two types of blood tests:

1. Nontreponemal Tests (Screening)

These are the first tests typically run. They don’t detect the syphilis bacteria itself, but instead look for antibodies your body produces in response to cell damage.

• Common tests: RPR (Rapid Plasma Reagin) and VDRL (Venereal Disease Research Laboratory)
• Pros: Fast, affordable, and good for tracking treatment response
• Cons: Can yield false positives, especially if other conditions are present

If this screening test comes back reactive, your blood will then be tested with a confirmation method.

2. Treponemal Tests (Confirmation)

Treponemal tests detect antibodies that specifically target Treponema pallidum, the bacterium that causes syphilis.

• Common tests: TP-PA, FTA-ABS, EIA, CIA
• Pros: More specific and confirmatory
• Note: These tests often stay positive for life—even after successful treatment.

What is the traditional vs. reverse testing sequence?

Different labs may follow different test sequences, both approved by the CDC:

• Traditional approach: Start with a nontreponemal screening test (e.g., RPR), then confirm with a treponemal test if positive.
• Reverse sequence: Start with a treponemal test (e.g., EIA), then follow with a nontreponemal test. If results don’t match, a third test may be used.

Both methods are accurate and widely used. Your doctor will interpret results based on the testing method used.

Are there direct tests for syphilis bacteria?

Yes, but they’re rare and typically used in special cases such as early-stage lesions or neurosyphilis.

• Dark-field microscopy: Visualizes syphilis bacteria from a lesion sample.
• PCR (Polymerase Chain Reaction): Detects genetic material from Treponema pallidum and may be used in complex or congenital cases.

These are not routine but can provide direct evidence of infection.

How long do results take?

• RPR and treponemal blood tests: 1–3 business days
• Microscopy or PCR tests: May be faster if done on-site (1–2 days)

How are results interpreted?

• Both tests reactive: Confirms a current or past syphilis infection.
• Screening reactive but confirmation negative: Possible false positive; further testing may be required.
• Both tests negative: No current infection. However, if you were recently exposed, retesting in 2–4 weeks is recommended.

Your provider will help determine whether you need treatment or follow-up based on these results.

What happens if you test positive?

If your test confirms a syphilis infection, treatment typically involves a single dose of penicillin (or another antibiotic if allergic). Early treatment is highly effective and can prevent long-term complications.

• Avoid sexual activity until treatment is completed and your provider clears you.
• Tell your partners so they can get tested too.
• Follow up if you have symptoms or are in a high-risk group. Your doctor may recommend a repeat test to confirm the infection has been cleared.

Why choose LabCafe for syphilis testing?

LabCafe offers a modern, fast, and confidential way to get tested:

• 🔒 Private testing at certified labs
• ⏱ Results in as little as 1–3 business days
• ✅ Easy online booking and no hidden fees

Ready to get tested? Visit TheLabCafe.com and book your syphilis test in minutes.

Frequently Asked Questions (FAQ)

Do I need a swab or urine sample for syphilis testing?

No—syphilis is tested using a simple blood draw only.

Can syphilis go away on its own?

No. Without treatment, syphilis can progress and cause serious health problems.

Will my test still be positive after treatment?

Yes. Treponemal tests often stay positive for life, which is why your provider will consider your full testing history.

Can I get syphilis again after treatment?

Yes. Having syphilis once does not make you immune. You can be reinfected.

Is syphilis testing covered by insurance?

Most insurance plans cover syphilis testing, especially as part of routine sexual health screening.

How soon after exposure can I get tested?

It can take 3 to 6 weeks for syphilis antibodies to show up. If you think you were exposed very recently, wait a few weeks or talk to your provider about when to test.