What are STIs?
Infections passed mainly through sexual contact.
- STIs are caused by bacteria, viruses, or parasites.
- They spread mainly through vaginal, anal, or oral sex.
- Common ones: chlamydia, gonorrhoea, syphilis, HIV, HPV, herpes.
- Anyone who is sexually active can get an STI.
Many STIs have no symptoms
You can have — and pass on — an STI without knowing.
- Many STIs cause no symptoms, especially early on.
- You can pass an STI to a partner without knowing you have it.
- Untreated STIs can cause serious harm, including infertility.
- This is why testing — not just symptoms — matters.
Symptoms to watch for
When symptoms do appear, they may include:
| Symptom | Note |
|---|
| Unusual discharge from genitals | Colour or smell change |
| Burning or pain when urinating | Common with several STIs |
| Sores, bumps, or blisters on genitals | See a worker promptly |
| Itching, or pain during sex | Worth checking |
| Often — no symptoms at all | Test even when you feel fine |
Symptoms can also come from non-STI causes. A test gives the real answer.
How to prevent STIs
Several layers of protection work together.
- Use condoms correctly, every time.
- Get tested regularly, and before a new partner if you can.
- Vaccines protect against HPV and hepatitis B.
- Fewer partners and mutual testing lower risk.
Key terms
- STI: Sexually transmitted infection, passed mainly through sexual contact.
- Asymptomatic: Having an infection with no symptoms.
- HPV: A common virus; some types cause cervical cancer — vaccine available.
- Testing: Checking for an infection, often even without symptoms.
- Curable vs. manageable: Many STIs are cured with medicine; others are controlled.
- Partner notification: Telling partners so they can be tested and treated.
Vaccines against STIs
Two STIs can be prevented by vaccination.
- The HPV vaccine prevents most cervical cancer.
- It works best given before sexual activity begins (adolescents).
- The hepatitis B vaccine prevents that infection.
- Vaccines are safe and widely recommended.
Myth or reality?
Tap each statement about STIs.
- You can always tell if someone has an STI (Myth) — Many STIs have no symptoms — you can't tell by looking. Testing is the only way to know.
- Condoms greatly reduce the risk of STIs (Reality) — Used correctly every time, condoms are the best protection during sex.
- Most STIs are treatable or curable (Reality) — Many are cured with medicine; others are well-managed.
- Getting tested means something is wrong with you (Myth) — Testing is normal, responsible health care — not a judgment.
More than 1 million curable STIs are acquired every day worldwide — over 350 million a year. They're extremely common, which is exactly why prevention and testing matter, and why there's no shame in it.
Helps prevent STIs or a myth?
Tap each, then whether it truly helps or is a myth.
- Using condoms every time (Helps prevent STIs)
- Getting tested regularly (Helps prevent STIs)
- HPV and hepatitis B vaccines (Helps prevent STIs)
- Judging by how a partner looks (A myth / doesn't help)
- Washing after sex to 'clean out' infection (A myth / doesn't help)
- Assuming no symptoms means no infection (A myth / doesn't help)
Testing and treatment
Testing is quick, confidential, and empowering.
- Testing is often a simple sample; results are confidential.
- Bacterial STIs are usually cured with a course of medicine.
- Viral STIs (HIV, herpes) are managed to stay healthy.
- Treat partners too, to prevent re-infection.
See a health worker if…
These signs mean get checked.
- Any unusual discharge, sores, burning, or genital itching.
- A partner tells you they have an STI.
- You've had unprotected sex or a condom broke.
- It's simply been a while — routine testing is wise.
Talking with partners
Honest conversation protects everyone.
- Talking about testing and condoms is a sign of respect.
- Agree on protection before sex, not after.
- If you test positive, tell partners so they can get care.
- These conversations get easier with practice.
Recap & what's next
- STIs are common and often have no symptoms.
- Prevent with condoms, testing, and vaccines.
- Most are treatable or curable — test without shame.
- Next: HIV — this could be its own module, or consent & relationships.
