STD Testing

This hub is for anyone seeking routine STI screening, testing after a potential exposure, evaluation of new symptoms (e.g., discharge, sores, pelvic/testicular pain), pregnancy care, or PrEP/sexual-health visits—and for clinicians organizing workups. Core labs include HIV 4th-generation Ag/Ab (± RNA NAT)syphilis algorithms (RPR/VDRL treponemal confirm or reverse sequence), chlamydia/gonorrhea NAAT from urine and exposure-site swabs (vaginal/cervical, rectal, pharyngeal), trichomonas NAATMycoplasma genitalium NAAT (as offered), HSV testing (lesion PCR/NAATtype-specific IgG), and hepatitis B/C panels. Results inform screening cadence, diagnosis/triage, and test-of-cure or reinfection screening—always with clinician guidance.


Why this matters: Many STIs are asymptomatic and site-specific; using the right test at the right anatomic site and time window is crucial. CDC/USPSTF recommendations underpin the guidance summarized here. 


Key Tests

Test Also called (synonyms) What it measures Typical prep Specimen Turnaround Related panels Use type Timing / Window notes & caveats
HIV-1/2 Ag/Ab (4th-generation) 4th-gen combo; p24 Ag Ab Early p24 antigenplus antibodies to HIV-1/2 None Blood (serum/plasma); some rapid tests Lab-dependent (often 1–3 days) Comprehensive STI Screen; MSM/PrEP Panel Screening / Diagnosis Window typically 18–45 days post-exposure; if recent/high-risk, reflex HIV-1 RNA NAT per CDC algorithm. CDC
HIV-1 RNA NAT HIV RNA; viral load (diagnostic context) Detects HIV RNA None Blood Lab-dependent Acute exposure panel; MSM/PrEP Panel Diagnosis Detects acute infection earlier; used when Ag/Ab is reactive or very recent exposure suspected. (Algorithm step 3). CDC Stacks
Syphilis algorithm RPR/VDRL treponemal confirm; or reverse sequence Nontreponemal titer (activity)  treponemalconfirm (lifetime exposure) None Blood 1–3 days typical Comprehensive STI Screen; Prenatal STI Panel Screening / Diagnosis / Monitoring Both traditional(RPR→treponemal) and reverse(treponemal→RPR→TP-PA) are acceptable; use same nontreponemal test type for follow-up titers. CDC
Chlamydia NAAT C. trachomatisNAAT; CT Bacterial nucleic acid Avoid urinating ~1 hrbefore urine specimen; first-catch urine Urine(first-catch), vaginal/cervicalrectalpharyngealswabs based on exposure 1–3 days typical Comprehensive STI Screen; Extragenital Add-On Screening / Diagnosis / Reinfection screen NAAT is preferredself-collected vaginal and rectal swabs are acceptable; test at exposure sites(including extragenital). Re-screen ~3 months after treatment. CDC 2CDC 2
Gonorrhea NAAT N. gonorrhoeaeNAAT; GC Bacterial nucleic acid Same as above Urine exposure-site swabs 1–3 days typical Comprehensive STI Screen; Extragenital Add-On Screening / Diagnosis / Reinfection screen Pharyngeal GC needs test-of-cure by NAAT at 7–14 days (earlier testing can be false-positive). Re-screen ~3 months for reinfection. CDC 1
Trichomonas NAAT T. vaginalisNAAT; Trich Protozoan nucleic acid None Vaginal swab; urine (women; men if offered) 1–3 days typical Comprehensive STI Screen Screening / Diagnosis / Reinfection screen For test-of-curedo not test before ~3 weeks after therapy (residual nucleic acid). Re-screen ~3 months in women. CDC 1
Mycoplasma genitalium NAAT M. genitalium; Mgen Bacterial nucleic acid None Urine or swab (site per product) 1–7 days Urethritis/Cervicitis panel Diagnosis / Monitoring Consider in persistent urethritis/cervicitis/PID per CDC; resistance-guided therapy where available. Not for routine screeningInsights
HSV testing HSV-1/2 lesion PCR/NAAT; Type-specific IgG Lesion PCR for active sores; IgGfor prior exposure Avoid topical agents on lesion before swab Lesion swab; Blood (IgG) 1–3 days Genital ulcer disease workup Diagnosis IgM is not recommended. Use lesion PCR when sores present; IgG indicates prior exposure, not site/timing. CDCInsights
Hepatitis B panel HBsAg, anti-HBs, anti-HBc (± IgM) Infection/immunity status None Blood 1–3 days MSM/PrEP Panel; Prenatal Panel Screening / Diagnosis / Risk Use 3-test panel; interpret patterns to distinguish current, past, or immune status. CDChepatitisb.uw.edu
Hepatitis C testing HCV Ab with reflex to RNA Past/current HCV; RNA confirms current None Blood 1–3 days MSM/PrEP Panel; Prenatal (risk-based) Screening / Diagnosis Begin with Ab reflex RNA; RNA is required to confirm current infection. CDC 2CDC 2
Cervical screening Pap cytology hrHPV DNA Cervical cancer screening None Cervical specimen Lab-dependent Women’s Health / Cancer Screening Screening (cervix-owners) Age/risk-based per USPSTF/ACOG(Pap/hrHPV). Not a blood test; cross-link to women’s health.

When to Test

  • Routine screening per risk/age (e.g., sexually active people <25; MSM; new/multiple partners; PrEP care; pregnancy).

  • After an exposure (condomless sex, partner diagnosed, sexual assault, needlestick): test now and schedule follow-up testing when window periods close (see HIV windows and retesting guidance).

  • Symptoms: genital/rectal/throat discharge or pain, sores/ulcers, dysuria, intermenstrual bleeding, pelvic/testicular pain.

  • Pregnancy care: first-trimester screening with repeat testing as risk indicates (ACOG/CDC).

  • Post-treatment: test-of-cure only when recommended (e.g., pharyngeal GCpregnancy for chlamydia), and re-screen at ~3 months to detect reinfection (CT/GC/Trich). 

Emergency red flags → in-person care now: Severe lower abdominal/pelvic pain (possible PID), unilateral testicular pain/swelling, fever with pelvic pain, rash joint pain (possible disseminated GC), neurologic/visual symptoms (possible neuro/ocular syphilis), pregnancy with pain/bleeding, severe sore throat with breathing/swallowing trouble, or signs of sepsis.


How to Prepare

  • Fasting: Not required for STI testing.

  • Urine NAAT: Provide first-catch urine (initial stream) and avoid urinating ~1 hour before collection. 

  • Swabs: Use exposure-site swabs (vaginal/cervical, rectal, pharyngeal). Self-collected vaginal and rectal swabs are acceptable and sensitive with NAAT. Avoid intravaginal products/douching before sampling. 

  • Lesion testing: For suspected HSV/syphilitic ulcers, collect as early as possible; avoid topical agents before sampling.

  • Medications/supplements: Tell the lab/clinician about recent antibiotics/antivirals (can yield false-negatives) and high-dose biotin (can interfere with some immunoassays). Do not stop prescribed meds without clinician advice. 

  • Timing: Respect window periods (e.g., HIV 4th-gen 18–45 days; RNA earlier). Plan follow-up testing if first test is too soon after exposure.


Interpreting Results

  • Use windows context: A negative test during a window period doesn’t rule out infection—schedule follow-up when the window closes; confirm positives per recommended algorithms.

  • HIV: Start with 4th-gen Ag/Ab; if reactive, follow the CDC algorithm with an HIV-1/2 differentiation assay, and RNA NAT if needed to detect acute infection. 

  • SyphilisRPR/VDRL titers track disease activity; treponemal tests often remain positive for life. Both traditionaland reverse algorithms are acceptable. 

  • CT/GC NAAT: Highly sensitive; test-of-cure is not routine except specific contexts (e.g., pharyngeal GC at 7–14 dayspregnancy for chlamydia at ~4 weeks). Re-screen ~3 months for reinfection. 

  • TrichomonasDo not test for cure before ~3 weeks (residual nucleic acid may cause false-positive). 

  • HSVLesion PCR/NAAT is preferred; IgG indicates past exposure; IgM is not recommended.

  • HBV/HCV: Use HBsAg/anti-HBs/anti-HBc panel for HBV status; for HCV, Ab with reflex RNA confirms current infection. 

  • Privacy & reporting: Some STIs are reportable; confidentiality is protected, but laws (e.g., minor consent) vary by state—review local policies and discuss with a clinician. 


Related Conditions & Topics

  • PrEP/PEP & HIV Prevention (eligibility discussion only; no dosing) — see Infectious Disease hub.

  • Pregnancy & Prenatal Screening — see Pregnancy & Fertility hub (first-trimester screens; repeat as risk indicates).

  • Urinary vs STI Symptoms — General Health explainer (dysuria differential).

  • Pelvic Inflammatory Disease (PID) / Epididymitis — triage explainers.

  • HPV & Cervical Screening — Women’s Health / Cancer Screening hubs.

  • Hepatitis A/B Immunity & Vaccination — Immunity & Titer hub.


Bundles & Panels — #test-list


FAQs

  1. How soon after exposure should I test for HIV, CT/GC, or syphilis?
    Window periods vary. HIV 4th-gen typically detects infection at 18–45 days (RNA even earlier). CT/GC NAATs are very sensitive but can be negative if done too soon after exposure; plan a follow-up test if your first test was within an early window. Syphilis serology may take several weeks to turn positive; confirm with the recommended algorithm and repeat if clinically indicated. Ask your clinician about retesting schedules

  2. Do I need throat or rectal swabs if I have no symptoms?
    Possibly. If you had oral or anal exposure, extragenital (pharyngeal/rectal) NAAT can detect infections that urine alone will miss

  3. Can antibiotics affect my results?
    Yes. Taking antibiotics/antivirals shortly before sampling can reduce NAAT yield and cause false-negatives. Tell the clinician/lab about recent medications.

  4. What’s the difference between test-of-cure and retesting for reinfection?
    Test-of-cure checks that treatment worked (only recommended in certain situations—e.g., pharyngeal gonorrhea at 7–14 dayschlamydia in pregnancy at ~4 weekstrichomonas ≥3 weeks). Retesting for reinfection is done at ~3 months because reinfection is common. 

  5. Is HSV IgM useful?
    No. HSV IgM is not recommended. Use lesion PCR for active sores and type-specific IgG for past exposure.

  6. Will my results be private?
    Results are confidential, but some STIs are reportable to public health; minor consent and confidentiality rules vary by state. Check local policies and discuss with your clinician.

  7. Do I need to fast?
    No fasting is needed for STI testing.

  8. What if my rapid HIV is positive?
    Confirm using the CDC laboratory HIV testing algorithm (Ag/Ab → differentiation assay → RNA NAT as needed) with a clinician. 


References

  • CDC — HIV Testing Overview (window periods).

  • CDC — HIV: Diagnostic Algorithm (Ag/Ab → differentiation → RNA NAT). 

  • CDC — Chlamydia (NAAT, self-collection, extragenital testing; test-of-cure and 3-month rescreen). 

  • CDC — Gonorrhea (pharyngeal test-of-cure at 7–14 days). 

  • CDC — Trichomoniasis (avoid test-of-cure <3 weeks). 

  • CDC — Retesting After Treatment (~3 months for CT/GC/Trich). 

  • CDC — Mycoplasma genitalium Testing (NAAT; targeted use). 

  • CDC — HSV Testing (IgM not recommended).

  • USPSTF — Chlamydia/Gonorrhea Screening (B recommendation; NAAT at anatomic sites). 

  • ACOG/CDC (Prenatal STI Screening) — first-trimester screening, risk-based repeats.

  • CDC — HBV (HBsAg/anti-HBs/anti-HBc panel) and HCV (Ab with reflex RNA). 

  • FDA — Biotin interference safety communication (immunoassays). 

  • Collection guidance — First-catch urine; avoid urination ~1 hour before CT/GC NAAT. 


Last reviewed: September 2025 — Medical reviewer: Ulta Lab Tests Medical Review Team

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There were over 2 million reported cases of STDs in the U.S. in 2017.

Are you protected and safe?

In this article, you'll learn about the different screening methods and the top tests to ask for. Plus you'll learn what each disease is and the possible signs and symptoms.

Don't wait—read on to discover what STD tests to ask for today for a safer tomorrow. 

What Are STDs?

STDs are sexually transmitted diseases that are normally spread by sexual intercourse. Some examples of STDs are Chlamydia, Gonorrhea, Herpes 1, and Syphilis.

You're at a higher risk of STDs if:

  • You have sex with someone who has had several partners
  • You don't use a condom
  • You share needles 
  • You trade sex for drugs or money
  • You have multiple sex partners

STDs are spread through oral, anal, and vaginal intercourse. And some STDs, such as HIV, can't be cured. Regardless, getting tested is essential. 

Why get tested?

If you have something, you'll have symptoms, right? Not always.

The majority of STDs out there will show no symptoms, so you might not even know. Your doctor might not be testing you for STDs, so it's important to be informed and ask for these tests. 

1. Chlamydia

Did you know that chlamydia is considered the most common curable STD? It affects the penile urethra in men and the cervix in women. 

Possible symptoms for men:

  • Burning during urination

  • Testicular swelling and pain

  • Discharge from the penis

Possible symptoms for women:

  • Abnormal vaginal discharge

  • Burning during urination

The best way to prevent chlamydia is to abstain from oral, anal, and vaginal intercourse. If you're sexually active, you'll want to maintain a monogamous relationship with someone who has no STDs. Regularly use protection such as condoms. 

Again, since it's common to have no symptoms, it's important to ask your doctor for tests. The good news is chlamydia is treatable. If you're uncomfortable speaking with your doctor, you can find an STD testing center near you. 

Testing for Chlamydia

How it's performed: A swab is taken of your urine or genital area

Keep in mind: If you've had anal or oral intercourse but not vaginal, let your doctor know ahead of time, because urine or vaginal samples may come back negative if you're infected. 

2. Gonorrhea

Along with chlamydia, gonorrhea is extremely common with 820,000 new infections every year. 

It's important to get treated for gonorrhea early on to avoid serious complications. Gonorrhea can lead to PID (pelvic inflammatory disease) and an increase in HIV if left untreated. PID can also lead to infertility, among many other serious complications. 

Possible symptoms in men:

  • Swollen testicles
  • Burning or painful urination
  • A white, yellow, or green discharge

Possible symptoms for women:

  • Bleeding between your period
  • Burning or painful urination
  • Increased vaginal discharge

Testing for Gonorrhea and Chlamydia

You'll want to get tested yearly for gonorrhea and chlamydia if:

  • You're a man who has sex with men
  • You're under 25
  • You're over 25 and more likely to get an STD, such as having multiple sex partners
  • You have HIV
  • You've been forced to have sex without your consent

Again, you should always get tested and be aware if you have an STD or not. But, getting tested yearly is even more important if you fall under one of the categories above. 

How it's performed: swab is taken of your urine or genital area.

Keep in mind: If you've had anal or oral sex, let your doctor know because just as chlamydia, they might not come up with a urine or vaginal test. 

3. HIV

HIV (human immunodeficiency virus) is the virus that's associated with AIDS. It's an STD that damages the white blood cells which are important in helping your body fight infections.

Transmission: It's transmitted by semen, vaginal secretions, exchange of bodily fluids, blood, and breast milk. While not curable, it's treated by drugs known as highly active antiretroviral therapy (HAART), or combined anti-retroviral therapy (cART). 

These drugs reduce the chance of HIV turning into AIDS. Some early symptoms of HIV are:

  • Feeling tired
  • Headaches
  • Fever
  • Sore throat
  • Thrush
  • Muscle and joint pain
  • Rash
  • Ulcers on the mouth or genitals
  • Diarrhea
  • Night sweats

These symptoms normally appear 1-2 months after transmission but can show up as soon as 2 weeks from exposure. Some people experience no symptoms, and you can have no symptoms for 10 years without knowing you have HIV. 

While men and women experience many similar symptoms, some women experience pap smears that show cervical dysplasia or other abnormal signs. You could also have PID as well. If you have severe or continual vaginal infections, they could also be a sign of HIV. 

Men can experience an ulcer on the penis. 

Testing for HIV

The only way to know for sure you're HIV-free is to get tested.

How it's done: A swab inside the mouth or a blood test.

Keep in mind: If you're worried about privacy, confidential and anonymous testing is available at many clinics. 

Difference Between HIV and AIDS

Often confused, there are differences between HIV and AIDS.

First, HIV can lead to AIDS, also known as stage 3 HIV. Thanks to different treatment options, people with HIV at any stage can lead long and healthy lives. 

HIV is considered a virus that can cause immune system deterioration. Once contracted, the immune system can't work as well as it should. HIV can be controlled through medication but not cured. 

AIDS, which is acquired immunodeficiency syndrome, is considered a condition that has symptoms that are different from person to person. A person could have different symptoms from the infections they develop from having a damaged immune system.

AIDS occurs once HIV breaks down a person's immune system. 

HIV doesn't always lead to AIDS, and taking the proper treatment can help prevent that. 

Protecting Against HIV 

Always use condoms for anal, vaginal, and oral intercourse.

Don't share or use needles. You can find needle exchange locations in your area if necessary.

Be cautious and always assume blood could be infectious. Wear latex gloves and use other barriers for protection against handling or touching blood. 

Get tested for HIV—it's the only way you'll know for sure it's HIV. Then if it's HIV, you can get the proper treatment to prevent the spread to others and take the proper precautions against it turning into AIDS. 

4. Herpes 

Herpes is a viral STD that comes in 2 forms: HSV-1 and HSV-2.

When someone gets a cold sore, that's what's known as HSV-1. HSV-1 is normally only found around the mouth and lips, while HSV-2 is most often found as genital sores. It's possible to transfer herpes from the mouth to genitals and the other way around as well. 

Herpes isn't curable but its symptoms are manageable with antiviral drugs.

It's important to understand the virus can still be spread to others even if you don't have symptoms. Although, when you're showing symptoms, you're more likely to spread the virus. 

Always wearing a condom during intercourse can decrease the spread of herpes but it's not 100% effective. An outbreak can be caused by both internal or external triggers such as stress, illness, or trauma. 

HSV-1 is transferred through the transfer of saliva, vaginal fluid, herpes sores, blisters, and semen. You can get HSV-1 from sharing drinks, kissing, or having oral sex with someone who has it. 

HSV-2 is transferred through vaginal fluid, semen, and any skin-to-skin contact with mucous membranes. If you have HSV-2, you can experience painful blisters and lesions on your upper thighs, anus, or genitals. 

Before the blisters appear you can experience body aches, fever, tingling, or pain in your genitals, buttocks, legs, hips, as well as swollen lymph nodes. 

Herpes Symptoms Men vs. Women

When you have symptoms, they can first occur around 2 weeks after exposure. In men, the sores usually appear on the penis, but can also appear on the buttocks, thighs, and scrotum.

Some men can also have discharge from the urinary tube, and swollen lymph nodes in the pelvis and groin area. You can also experience pain or difficulty urinating as well. 

For women, the sores can appear on the outer lips also known as the labia majora, entrance of the vagina, or the inner lips (labia minora). You can also have sores appear on the buttocks, thighs, clitoris, or anus. Some experience watery discharge from their vagina. 

Some women who experience symptoms can also have a yeast infection as well. Outbreaks that are recurring in women can be due to pregnancy, menstruation, not eating healthy, or exposure to sunlight.

Testing for Herpes

The only way to know if you have herpes is to get tested

How it's done: Herpes (with no symptoms), you'll receive a blood test from your arm or receive a fingerstick. You'll also want to ask for a type-specific IgG test. 

If you have genital herpes with symptoms, you'll receive a swab from the affected area. You might receive a negative test, so it's important to follow up with a blood test as well.

You'll want this test done as soon as possible since the viral culture isn't as accurate after 48 hours. 

5. Syphilis

Syphilis is an STD that, left untreated, can cause major complications. It's transmitted by having direct contact with syphilis sores which can be on the mouth or genitals. It can be spread by oral, anal, and vaginal intercourse. 

Condoms can reduce the risk but not completely eliminate the risk of this STD. They appear as small painless sores, which can heal on their own, but you'll still be infected. Syphilis can easily be tested and is treatable. 

Syphilis affects men and women mostly the same way as far as symptoms go. A symptom for men is a small ulcer that's reddish-brown, small, and flat. Sometimes the ulcer can be found in the anus, not just the mouth or genitals. 

For women, the ulcer is normally found inside the vagina. The ulcer is normally painless and has no odor. 

Syphilis Testing

Syphilis testing is done by drawing blood or taking a sample from the ulcer. If you're pregnant, you'll especially want to be tested for syphilis. 

6. Trichomoniasis

Trichomoniasis is a common STD that can be misdiagnosed by women as a yeast infection or bacterial vaginosis since the symptoms can be similar. Some of the symptoms can be pain during intercourse, strong odor, frothy discharge, irritation, or itching. 

Men can get trichomoniasis but normally don't have any symptoms. If you have this STD, you'll want your partner to get treated as well so they don't give it back to you. 

Trichomoniasis Testing 

The test will be a swab of the infected area or sample of discharge. It tends to be harder to find in men than women. 

7. Hepatitis

Hepatitis is composed of Hepatitis A, B, or C. Hepatitis is transferred in different routes but they can all negatively affect your liver. Hepatitis B is often thought of to be sexually transmitted, but Hepatitis C can be as well. 

There is a Hepatitis B vaccine, as well as a vaccine for Hepatitis, you can get to protect yourself. Hepatitis B can lead to cirrhosis, liver cancer, and scarring of the liver. Hepatitis A is transferred through food and can cause fever and jaundice. 

Testing for Hepatitis

A blood test is taken to test for hepatitis. The only way to know if you have hepatitis is to get tested. Hepatitis is curable. 

Get STD Screening

It's important to learn as much as possible about each STD out there and take the proper precautions to prevent yourself from contracting it. Even if you show no symptoms, the only way to know is to get an STD screen. 

Would you like to learn more and get started on STD screening?