This is an overview of 10 common sexually transmitted conditions. But, let’s start with a definition.
What are STIs?
STIs (Sexually Transmitted Infections) – or STDs (Sexually Transmitted Diseases) – are infections passed from one person to another through sexual contact, including vaginal, anal, and oral sex. They can be caused by bacteria, viruses, or parasites.
Their two main traits are that they often present with absolutely no symptoms at all, but most are highly treatable (and often curable) when caught early.
What it is: A very common bacterial infection that affects the cervix, urethra, rectum, or throat.
Common signs: Often no symptoms; sometimes pain when passing urine, unusual discharge, or bleeding between periods.
When to Worry:
Symptoms develop after sexual contact
A sexual partner is diagnosed with chlamydia
When to See a Doctor:
For routine testing if sexually active, or promptly if symptoms appear.
What it is: A bacterial infection affecting the genitals, throat, or rectum, which can lead to fertility issues if left untreated.
Common signs: Thick green or yellow discharge, pain when urinating, and pelvic or testicular pain.
When to Worry:
Pain or discharge when urinating
Symptoms worsening quickly
When to See a Doctor:
As soon as symptoms appear. Early treatment prevents long-term complications.
What it is: A viral infection that stays in the body long-term, causing periodic flare-ups.
Common signs: Painful blisters or sores around the genitals or rectum; tingling or itching.
When to Worry:
First outbreak (often the most uncomfortable)
Sores become severely painful or show signs of secondary infection
When to See a Doctor:
Soon. For diagnosis and treatment advice if sores are painful or recurrent.
What it is: A very common virus; some types cause harmless skin growths, while others increase cancer risk.
Common signs: Often none; sometimes genital warts or abnormal cell changes.
When to Worry:
New, unexplained warts
Abnormal cervical screening test results
When to See a Doctor:
Soon. For warts or concerns, and attend routine cervical screening if eligible.
What it is: A virus that attacks and weakens the immune system over time, which is highly manageable with modern medication.
Common signs: Early flu-like illness (fever, rash, sore throat) or no symptoms for many years.
When to Worry:
Possible exposure through unprotected sex or shared needles
High risk group or any unexplained long-term illness
When to See a Doctor:
As soon as possible for testing. Early treatment is highly effective at protecting your health.
What it is: A bacterial infection that develops in distinct stages and can cause serious internal damage if left untreated.
Common signs: A painless sore (chancre), a non-itchy rash (often on palms/soles), and flu-like symptoms.
When to Worry:
Any unexplained, painless sore or new body rash
When to See a Doctor:
Immediately. Early treatment with antibiotics easily cures the infection and prevents permanent damage.
What it is: A parasitic infection caused by a tiny organism, easily spread during unprotected sex.
Common signs: Foul-smelling discharge, genital itching, and discomfort when urinating (often no symptoms in males).
When to Worry:
Persistent genital irritation or unusual frothy discharge
When to See a Doctor:
Soon. For testing and treatment. Both partners usually need treatment to prevent re-infection.
What it is: A virus affecting the liver that can cause acute illness or lead to a chronic, long-term infection.
Common signs: Extreme fatigue, nausea, yellowing of the skin/eyes (jaundice), and dark urine.
When to Worry:
Flu-like illness accompanied by jaundice (yellow skin colour)
Known exposure to infected blood or bodily fluids
When to See a Doctor:
Promptly. Testing and monitoring are important, and emergency preventative treatment can be given if exposed recently.
What it is: Small parasitic insects living in coarse human body hair, most commonly pubic hair.
Common signs: Intense itching in the affected areas, visible tiny lice, or small eggs attached to hairs.
When to Worry:
Persistent itching that disrupts sleep or causes raw skin from scratching
When to See a Doctor:
Soon. For diagnosis and treatment advice regarding specialized insecticidal creams or lotions.
What it is: Small, benign growths on or around the genitals or anus caused by certain low-risk types of HPV.
Common signs: Small, flesh-coloured or pink bumps that can appear alone or in clusters like a cauliflower; usually painless.
When to Worry:
New, rapidly spreading, or bleeding warts
When to See a Doctor:
For confirmation and professional treatment options, such as freezing or topical creams.
Note. If accompanied with lower abdominal pain and fever, there may be a pelvic infection (i.e. it is ascending infection) – e.g. pelvic inflammatory disease (PID).
Many STIs cause no symptoms – regular screening is the only way to know your status for sure.
Do not ignore potential exposure or symptoms – early medical evaluation ensures quick treatment and stops the spread.
Most sexually transmitted infections are benign and highly treatable – but early diagnosis is key.
Sexually transmitted symptoms are standard medical concerns – never let embarrassment delay a visit to the doctor.
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