SEXUAL HEALTH GUIDE
Different infections become detectable at different times, and the test and sample matter. Use this guide to understand common testing windows, what an early negative result can mean, and when to seek help immediately.
There is no one-day answer for “an STI test.” A test for chlamydia or gonorrhoea, an HIV laboratory blood test and a syphilis blood test all answer different questions at different times. Testing very early can be useful as a baseline or for symptoms, but a negative result may not rule out infection from the recent exposure.
Do not wait for a calendar date if you have symptoms, a partner has tested positive, or HIV exposure may have happened within the last 72 hours. Seek clinical assessment. [3][9][4]
Choose a time band to read general context. This does not assess your personal risk or replace a clinician's advice.
These are source-reported detection ranges or screening points, not Ovio laboratory protocols. Every row has a recorded clinical review. A range's first day does not mean a negative result on that day excludes infection.
| Infection | Common test and sample | Timing from exposure | Repeat / interpretation |
|---|---|---|---|
| ChlamydiaNAAT / PCR | NAATUrine or vaginal/rectal swab; site depends on exposure | Around 14 days (cited NHS screening point)[4][5][10] | Discuss repeat testing if the first sample was taken before the window or symptoms/partner notification arise.The NHS two-week point is screening guidance, not a claim that every earlier test is negative. |
| GonorrhoeaNAAT / PCR | NAAT; culture may be needed in specific clinical situationsUrine or vaginal, throat or rectal swab as indicated | Around 14 days (cited NHS screening point)[4][5][11] | Discuss repeat testing if the first sample was early or an exposed site was not sampled.A urine result does not assess the throat or rectum. Culture can matter for treatment decisions. |
| HIVNAT / RNA | NAT / RNABlood | 10–33 days (CDC reported detection range)[2][3] | A clinician should plan follow-up with the appropriate test, particularly after PEP/PrEP use.Not a routine replacement for the standard HIV testing algorithm. CDC's range is when infection can usually be detected. |
| HIV4th generation Ag/Ab | Laboratory antigen/antibody from a veinVenous blood | 18–45 days (CDC reported detection range)[2][3] | If tested during the window, follow the clinician's repeat-testing plan. PEP/PrEP can change interpretation.This CDC range applies to a laboratory test using venous blood, not every rapid test. |
| HIVRapid Ag/Ab | Rapid antigen/antibody from a finger stickFinger-stick blood | 18–90 days (CDC reported detection range)[2] | A negative result inside the window needs appropriate follow-up testing.Do not substitute the shorter venous laboratory window for this test. |
| HIVAntibody | Antibody testBlood or oral fluid, depending on product | 23–90 days (CDC reported detection range)[2] | A negative result inside the window needs appropriate follow-up testing.Many rapid and self-tests detect antibody only; confirm the product and sample. |
| SyphilisBlood test | Treponemal and non-treponemal serologyBlood; lesion assessment if present | Around 84 days (cited NHS screening point)[4][9] | An earlier negative result may need repeat serology; a known partner exposure needs prompt clinical assessment.NHS service guidance uses a 12-week window. CDC advises presumptive care for some recent contacts even with negative serology. |
| Hepatitis BAntigen / antibody | HBsAg and other markers chosen by a clinicianBlood | 7–84 days (CDC reported detection range)[6][7] | Marker selection, vaccination history and follow-up depend on the exposure and clinical assessment.CDC states HBsAg may appear from 1–2 to 11–12 weeks. Recent exposure may also require urgent vaccine/immune-globulin assessment. |
| Hepatitis CNAT / RNA | HCV RNABlood | 7–14 days (CDC reported detection range)[8] | Follow-up depends on the exposure and clinician's testing plan.CDC describes RNA as usually detectable around 1–2 weeks; sexual transmission risk varies by context. |
| Hepatitis CAntibody | HCV antibody, with RNA follow-up when indicatedBlood | 56–77 days (CDC reported detection range)[8] | Early antibody-negative results may need RNA testing or later follow-up.CDC describes an 8–11-week antibody window. Antibody alone does not establish current infection. |
| TrichomoniasisNAAT / PCR | NAAT where indicatedVaginal swab or urine, depending on test | No universal post-exposure calendar date is given here.[15] | Assessment and any repeat test depend on symptoms, test and treatment history.Test selection differs by anatomy and clinical context. |
| Mycoplasma genitaliumNAAT / PCR | NAAT when clinically indicatedUrine or genital swab | Not a routine asymptomatic screening date.[14] | A clinician may consider testing with persistent or recurrent symptoms.CDC does not recommend general asymptomatic screening. |
| Genital herpes / HSVLesion swab | Lesion NAAT when sores are presentSwab of an active lesion | Seek assessment while a lesion is present; no single post-exposure date fits.[12] | Type-specific blood antibody testing has limited, situation-specific use.Routine HSV-2 blood screening without symptoms is not recommended by CDC. |
| HPVScreening test | Cervical screening where eligibleCervical sample | Not a universal test a set number of days after one exposure.[13] | Follow the relevant cervical screening pathway or clinician advice.HPV tests are not a general STI test for every person or exposure. |
Unsure which test or sample applies? Read Ovio's STI testing service and ask a clinician about the specific assay and exposure sites.
PEP is post-exposure prophylaxis. When clinically appropriate, it should be started as soon as possible and no later than 72 hours after exposure. Seek urgent medical assessment now rather than waiting for an HIV test. A baseline test may be part of care, but it cannot exclude infection from an exposure that just happened. [3]
Ovio does not currently state that it provides PEP. A Bangkok clinic that lists PEP care is Bangkok Safe Clinic; an emergency department is another route for urgent assessment.
This educational preview uses the same clinical dataset as the table. It is not a risk calculator, diagnosis or recommendation to wait. The standalone STI test window calculator keeps the tool focused; this embedded version lets you use it while reading the guidance.
[2][4][3] This is a map of questions to ask, not a personal schedule.
Detects genetic material from the organism. Chlamydia and gonorrhoea NAATs can use samples from specific body sites; HIV NAT detects viral RNA in blood.
Detects a component associated with an infection. Hepatitis B surface antigen and HIV p24 antigen are different markers with different interpretation.
Detects the body's immune response. Antibody development takes time and can be affected by the clinical situation.
A laboratory fourth-generation HIV test detects antigen and antibody. Its CDC window is not interchangeable with that of a rapid finger-stick combination test.
A testing window is the time between acquiring an infection and a test being able to detect it. An incubation period is the time until symptoms appear. You can have no symptoms and still test positive, or have symptoms before a routine screening point. An early negative needs interpretation in light of both.
A NAAT checks for bacterial genetic material. A urine or vaginal sample may be used for genital infection, while rectal exposure can require a rectal sample. An early negative may need repeating. The two-week point in this guide comes from NHS screening guidance; it is not a promise about an individual assay. [5][10]
NAAT is widely used, but a culture can be important when treatment failure or antibiotic resistance is a concern. Throat, rectal and genital sites can require different samples. A negative urine result cannot answer what is happening in an untested throat or rectum. [5][11]
NAT, laboratory venous-blood antigen/antibody, finger-stick rapid combination and antibody-only tests have different CDC windows. The lower end is not a universal day on which a negative result rules out infection. PEP or PrEP use can change the follow-up approach; tell the clinician what you have taken. [2][3]
Blood testing uses treponemal and non-treponemal tests with different roles. Early infection can precede a positive blood result. A sore or a partner diagnosis deserves assessment now; CDC advises presumptive treatment for some recent contacts even when serology is negative. NHS screening guidance uses 12 weeks for the window. [9][4]
A clinician chooses markers such as HBsAg and hepatitis B antibodies in light of vaccination and past infection. HBsAg can appear at different times after exposure, so a single early blood result is not the whole assessment. Recent exposure may require urgent advice about vaccination or hepatitis B immune globulin. [6][7]
HCV RNA can be detectable before antibodies. A positive antibody test does not by itself show current infection; RNA testing helps establish that. Whether HCV testing is indicated after sexual contact depends on the exposure and clinical context, especially possible blood exposure. [8]
An active herpes sore is best assessed while present, often with a lesion swab; routine HSV blood screening is not advised for most people without symptoms. Trichomonas NAAT can be useful when indicated, but there is no universal date here. CDC does not recommend routine asymptomatic M. genitalium screening. HPV testing belongs to cervical screening pathways, not a single post-exposure countdown. [12][15][14][13]
A negative result answers only the question the chosen test, sample and date could answer. Before interpreting it, check:
If the test was inside its window, ask when and how to repeat it. A baseline result can still be useful for comparison, but it should not create false reassurance. Symptoms or a partner's positive result call for assessment regardless of the calendar. [2][3][9]
Tell the clinician which body sites were involved in the exposure. Depending on the infection and anatomy, testing can involve urine or urethral samples, vaginal swabs, throat swabs or rectal swabs. A negative urine test does not necessarily rule out gonorrhoea or chlamydia in a throat or rectum that was not sampled. This advice applies to the exposure sites, not to someone's identity or sexual orientation. [11][10]
Unusual discharge, pain when urinating, sores or blisters, a rash, pelvic or lower-abdominal pain, testicular pain or swelling, or unusual bleeding can warrant clinical assessment now. These symptoms have many possible causes; this page cannot diagnose them. [11][12][9]
Visitors do not need to wait until they return home to seek advice. If you are leaving Thailand before a full testing window has passed, ask what can be assessed now, which assay and sample sites a clinic will use, and what repeat testing may be needed after travel. Keep the test name and result so a clinician elsewhere can interpret them. Avoid assuming that a “full panel” includes every infection or exposed site.
Ovio's STI testing service describes its current visit model. Contact the team to confirm which tests and samples are available; this guide does not promise a particular assay, price or turnaround time.
For context beyond an individual result, explore Ovio's source-linked Thailand HIV statistics and Thailand STI statistics. Those reports describe population trends; they cannot estimate your personal chance of infection.
It depends on the infection, test and any symptoms. Seek help promptly for symptoms, a partner diagnosis or possible HIV exposure within 72 hours. Screening windows in the table are general guidance, not a personalised schedule.
An immediate test can sometimes establish a baseline or investigate symptoms, but a negative result the next day cannot generally rule out a new infection from that exposure.
For some tests, yes. The cited NHS guidance uses two weeks for chlamydia and gonorrhoea screening. HIV test windows differ by technology. An early test may still have clinical value; ask what it can and cannot tell you.
No. HIV and syphilis blood-test windows can extend later, and some infections do not have a useful single post-exposure screening date.
The cited NHS guidance uses two weeks for chlamydia and gonorrhoea screening. Other tests may have longer or test-specific windows, so a two-week panel cannot answer every question.
The cited NHS sexual-health services use a two-week screening window after exposure for both. Symptoms or a partner diagnosis should prompt advice sooner. The sample must reflect the sites of exposure.
CDC lists different ranges: NAT 10–33 days; laboratory venous antigen/antibody 18–45 days; rapid finger-stick antigen/antibody 18–90 days; antibody-only 23–90 days. These are detection ranges, not Ovio-specific recommended appointments.
Four weeks falls within CDC's 18–45-day range for a laboratory venous antigen/antibody test. A negative result at that point needs interpretation with the specific assay, exposure and any PEP/PrEP use; do not treat the lower end of a range as a guarantee.
A clinician may test now if there are symptoms or a known contact. The cited NHS service uses a 12-week window for screening; a negative earlier test can require follow-up.
Keep the result and ask which infection and sample it covered. A negative test inside its window may need repeating. New symptoms or a partner's positive result should prompt assessment rather than waiting silently.
Seek clinical advice promptly and say which infection your partner was diagnosed with. Assessment, testing and sometimes treatment may be appropriate even before a routine screening window has passed.
Yes. Symptoms and test detectability follow different timelines, and some infections can be asymptomatic. Screening decisions should reflect exposures and clinical advice.
No. A urine sample does not test blood-borne infections, and it does not automatically assess a throat or rectum exposed during sex.
Possibly, if those sites were exposed. Tell the clinician which sites were involved so the right samples can be considered. A urine sample cannot stand in for an untested throat or rectum.
You can seek assessment in Bangkok. If the full window has not passed, ask what today's result means, what test was used and how follow-up can be arranged after travel.
Visitors can seek assessment in Bangkok. Ask any provider which tests and samples are available, how results are communicated and whether you need follow-up after leaving Thailand.
Tell the clinician about any antibiotics taken before sampling. They can affect the investigation and interpretation for some bacterial infections; do not self-treat or delay assessment to fit an online date.
Yes. Tell the clinician if you use or recently used either. HIV testing and follow-up after antiretroviral exposure can differ from a simple calendar calculation.
Yes: seek clinical assessment now. A clinician can examine symptoms and choose appropriate tests or treatment even when a routine post-exposure screening window has not passed.
This draft uses CDC and NHS guidance and lists Thailand's national testing guideline for clinician cross-check. Numeric ranges are shown with their source and test type. They are not Ovio-specific test protocols. The table and calculator have recorded clinician review.