A "full" STD panel usually tests for chlamydia, gonorrhea, syphilis, HIV, and often hepatitis and trichomoniasis — from a urine sample, a swab, and a blood draw. What it routinely leaves out surprises people: genital herpes (HSV) and HPV aren't part of a standard panel, and many panels skip throat and rectal sites.
| Item | Days after exposure |
|---|---|
| Chlamydia / gonorrhea (NAAT) | ~14 |
| HIV — NAT | 10–33 |
| HIV — antigen/antibody | 18–45 |
| HIV — rapid antibody | 23–90 |
What "full" actually covers — and the gaps nobody mentions
There's no single legal definition of a "full" panel, so what you get depends on who's ordering it. A typical comprehensive screen checks for chlamydia, gonorrhea, syphilis, and HIV, and frequently adds hepatitis B, hepatitis C, and trichomoniasis. That bundle catches the infections that are common, treatable, and often silent.
Most default panels do not include herpes (HSV-1/HSV-2) blood testing. Routine HSV antibody screening in people without symptoms isn't recommended, because false positives are common and a positive antibody result doesn't tell you where or when. HPV is the other big omission. There's no blood test for it, and HPV screening (a Pap or HPV test) is done through cervical sampling rather than a generic panel. If you want HPV checked, you typically arrange that separately, and for some patients a self-collected hpv test is now an option.
The third gap is anatomical. If you order a urine-only panel but have receptive oral or anal sex, the test can miss a throat or rectal infection entirely, because chlamydia and gonorrhea live where the exposure happened. Catching those requires extragenital swabs of the throat and rectum, so ask for them by name.
How the test actually works
Most STIs are tested from a simple sample. Chlamydia, chlamydia and gonorrhea, plus trichomoniasis, are detected from a urine cup or a self-collected swab using a NAAT — a nucleic acid amplification test that copies and detects the organism's genetic material. HIV, syphilis, and hepatitis come from a quick blood draw. In practice that's minutes in the chair: you pee in a cup or swab yourself in a private bathroom, a phlebotomist takes a small tube of blood, and results land in a day or a few.
NAATs are the most sensitive tests available for chlamydia and gonorrhea, so guidelines recommend them over older culture or antigen methods. Modern NAATs are highly accurate, with specificity around 99% CDC. That high specificity means a positive is very likely a true positive, and a self-collected vaginal swab performs as well as a clinician-collected one.
Why test at all if you feel fine? Many STIs cause no symptoms, so how you feel tells you nothing about your status. Screening catches silent infections before they cause harm, which is why the USPSTF recommends routine chlamydia and gonorrhea screening for sexually active women under a certain age and others at increased risk USPSTF.
When to test after exposure: the window period
There's a gap between when you're exposed and when a test can actually detect the infection: the window period. Test inside that window and you can get a falsely reassuring negative, because the infection simply isn't detectable yet. This timing detail trips people up with at-home kits.
For chlamydia and gonorrhea, a NAAT is generally reliable about two weeks after exposure. If you test sooner because you're worried, that's fine, but a too-early negative should be repeated later when a recent exposure is possible. For HIV, the window depends on which test is used:
- A nucleic acid test (NAT) can detect HIV roughly 10–33 days after exposure CDC.
- An antigen/antibody lab test detects it about 18–45 days after exposure.
- A rapid antibody test detects it about 23–90 days after exposure, the widest window, so a quick negative early on may need repeating.
Testing before the window closes is the main cause of a false negative. The test isn't broken; the infection just hasn't reached detectable levels. For a full breakdown by infection and test type, see our guide on when to test after exposure.
Where to get tested and what it costs
You're rarely far from low-cost testing. Care is available at doctors' offices, health departments, Planned Parenthood, and Title X family-planning clinics, and at-home and self-collection kits ship to your door. The US has roughly 16,000 federally funded community health centers and about 4,200 Title X family-planning clinics, plus tens of thousands of other public STI clinics, most offering free or income-based sliding-scale care HRSA.
Cost ranges from free at a public clinic to a flat fee for an at-home kit. If you go the home route, watch the timing: order and collect within the right window so you're not paying for a result you'll have to repeat. To weigh accuracy, turnaround, and price across services, compare testing providers, and when you're ready to book, here's how to get tested.
Reading your results and how accurate they are
A NAAT result for chlamydia or gonorrhea is straightforward: detected or not detected, and a positive is highly reliable thanks to that ~99% specificity. Blood-based screens for HIV and syphilis work differently. They use a two-step process to guard against false positives: an initial screening test is followed by a different confirmatory test, and the result isn't final until the confirmatory step agrees.
This matters most with rapid HIV tests. A reactive (preliminary positive) rapid result is not a diagnosis; it must be confirmed with a follow-up lab test before it counts. Syphilis testing follows the same logic, pairing a screening assay with a confirmatory one CDC, 2024. A single reactive screen is a reason to confirm, not to panic.
| What's tested | Sample | Method | Reliable after exposure |
|---|---|---|---|
| Chlamydia, gonorrhea, trichomoniasis | Urine or self-swab | NAAT | ~2 weeks |
| HIV (NAT) | Blood | Nucleic acid | ~10–33 days |
| HIV (antigen/antibody) | Blood | Lab immunoassay | ~18–45 days |
| HIV (rapid antibody) | Blood/oral fluid | Antibody, confirmed if reactive | ~23–90 days |
| Syphilis | Blood | Two-step (screen + confirm) | Varies |
If a result is positive
Most bacterial STIs — chlamydia, gonorrhea, syphilis, trichomoniasis — are curable, usually with a short course of antibiotics or a single injection, and your partner(s) should be treated too. Don't self-treat; get a confirmed diagnosis and the right regimen. See our chlamydia guide for what diagnosis and treatment look like in detail.
When to see a clinician
Book a visit if you have symptoms — unusual discharge, burning when you pee, sores, pelvic or testicular pain — or a known exposure to a partner who tested positive. See someone too if a rapid test came back reactive and needs confirmation, if you're pregnant, or if a too-early negative needs repeating after the window closes. Even with no symptoms, routine screening on a schedule that fits your risk catches the infections that hide.