Common STI Symptoms Everyone Should Know

Many STIs Have No Symptoms

One of the most important things to understand about sexually transmitted infections is that many do not cause obvious symptoms, especially in the early stages.

• Chlamydia — Often has no symptoms, particularly in women.
• Gonorrhoea — May cause no symptoms or mild symptoms that are easily missed.
• HPV — Usually has no symptoms; some types can cause genital warts or cell changes.
• HIV — Early infection may cause flu-like symptoms that resolve, followed by a long period with no symptoms.

This is why regular testing is important for anyone who is sexually active, even if you feel fine.

Common Warning Signs

While many STIs can be silent, the following symptoms may indicate an infection:

Discharge Changes

• Unusual vaginal discharge (change in colour, amount, or smell)
• Discharge from the penis
• Rectal discharge

Pain

• Pain when urinating (burning or stinging)
• Pelvic pain
• Pain during sex
• Testicular pain or swelling
• Lower abdominal pain

Skin Changes

• Sores, blisters, or ulcers on or around the genitals, anus, or mouth
• Genital warts (small bumps or growths)
• Rash on the body, palms, or soles
• Itching in the genital area

Bleeding

• Bleeding between periods or after sex
• Heavier periods than usual

Other

• Flu-like symptoms shortly after a risk exposure (possible acute HIV)
• Swollen lymph nodes
• Unexplained fatigue or weight loss

STI-Specific Symptoms

Chlamydia

• Often no symptoms
• May cause unusual discharge, pain when urinating, or lower abdominal pain

Gonorrhoea

• May cause yellow or green discharge, pain when urinating
• Can affect the throat and rectum

Genital Herpes

• Painful blisters or sores around the genitals or anus
• May recur periodically
• First outbreak is often the most severe

Syphilis

• Painless sore (chancre) at the site of infection (stage 1)
• Body rash, including palms and soles (stage 2)
• Can cause serious complications if untreated

HPV

• Often no symptoms
• Some types cause genital warts
• Certain types are linked to cervical and other cancers

Trichomoniasis

• Frothy, yellow-green vaginal discharge with a strong smell
• Genital irritation and pain during urination or sex

HIV

• Acute infection may cause flu-like symptoms 2–4 weeks after exposure
• Long asymptomatic period follows
• Without treatment, progresses to AIDS

Testing and Screening

• Who should get tested? Anyone who is sexually active, particularly if you have new or multiple partners.
• How often? Testing frequency depends on your risk factors — discuss with a healthcare provider. Annual screening is a common recommendation.
• What does testing involve? Depending on the STI, tests may involve urine samples, blood tests, or swabs from affected areas.
• Where can you get tested? Sexual health clinics, hospitals, some pharmacies, and GP offices.

Only a clinician or a test can diagnose an STI. Symptoms alone cannot confirm or rule out infection.

Prevention

• Condoms — Consistent condom use significantly reduces the risk of most STIs.
• Regular testing — Knowing your status helps protect you and your partners.
• Vaccination — HPV vaccination protects against the types of HPV that cause most cervical cancers and genital warts. Hepatitis B vaccination is also available.
• Communication — Talk with partners about testing and safer sex practices.
• Limiting partners — Fewer sexual partners reduces exposure risk.

When to Seek Professional Help

See a healthcare provider if:

• You notice any unusual symptoms in the genital area
• A partner tells you they have been diagnosed with an STI
• You have had unprotected sex and want to get tested
• You are starting a new sexual relationship
• You have not been tested recently and are sexually active