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A clear guide to sexually transmitted infections: the most common types, symptoms, why testing matters and how they are treated.
By Editorial Team · Updated · 2 min read
This article is awaiting review by a qualified medical professional.
Quick answer
Common STIs include chlamydia, gonorrhea, syphilis, HPV, herpes and HIV. Many cause no symptoms, so testing is the only way to know. Bacterial STIs are curable with antibiotics, and vaccines prevent HPV and hepatitis B.
Sexually transmitted infections (STIs) are common and affect people of every age, gender and sexual orientation. Many are easily treated, and many cause no symptoms, so testing is the only way to know your status.
| Infection | Cause | Curable? |
|---|---|---|
| Chlamydia | Bacteria | Yes, with antibiotics |
| Gonorrhea | Bacteria | Yes, with antibiotics |
| Syphilis | Bacteria | Yes, with antibiotics |
| Trichomoniasis | Parasite | Yes, with medicine |
| HPV | Virus | Usually clears on its own; vaccine prevents most cancer-causing types |
| Genital herpes | Virus | No, but treatable |
| HIV | Virus | No, but treatment allows a long, healthy life |
| Hepatitis B | Virus | Vaccine-preventable; treatable |
Many people have no symptoms. When present, they may include:
Untreated STIs can cause serious problems, including pelvic inflammatory disease, infertility, pregnancy complications and increased risk of HIV. Testing is quick, usually a urine sample, swab or blood test, and confidential at most clinics.
Consider testing if you have a new partner, more than one partner, a partner who has an STI, or any symptoms. Ask a healthcare provider how often you should be screened.
Bacterial and parasitic STIs are treated with antibiotics or other medicines. Finish the full course and avoid sex until you and your partner(s) have been treated. Viral STIs are managed with antiviral medicines and regular follow-up.
See a healthcare provider promptly if you notice any symptoms or think you may have been exposed. There is no shame in getting tested, and it is one of the best things you can do for your health and your partners.
Yes. Many STIs, including chlamydia, gonorrhea and HIV, can cause no symptoms for a long time, so regular testing matters.
Each infection has a window period before a test can detect it, from days to a few weeks or more, and a repeat test may be needed. A clinician can advise on timing. If you were exposed in the last 72 hours, contact a clinician straight away, because HIV post-exposure treatment must start within that time.
Bacterial and parasitic STIs such as chlamydia, gonorrhea, syphilis and trichomoniasis can be cured with treatment. Viral STIs such as herpes and HIV cannot be cured but can be managed effectively.
This article is for educational purposes only and does not replace advice from a doctor or other qualified health professional. See our medical disclaimer.
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