This tiny parasite can infect the penis, vagina, the tube that carries pee from the bladder, and the prostate gland in men.
Many people don’t have symptoms so it is important to get tested.
It can cause a smelly discharge, itching, pain or a burning feeling when peeing or pain during sex in women.
What is trichomonas infection and how is it caught?
Trichomonas infection is a tiny parasite (you need a microscope to see it).
It's spread through unprotected sex or sharing sex toys.
How can I avoid catching trichomonas infection?
If you're going to have sex, always use a condom (or a dam) and have safer sex.
Around half of people with trichomonas have no symptoms and don't know they're infected but can still pass it on.
If you think you or your partner may be at risk, it's important you get tested.
Those who do get symptoms may experience a green or yellow fluid coming from the penis or vagina. Sometimes this has a fishy smell.
You might have itching or soreness around your genitals or pain or a burning feeling when peeing.
Women can find sex uncomfortable or even painful.
Testing may involve giving a urine (pee) sample.
If you have a discharge (green or yellow fluid coming from your penis or vagina) the nurse or doctor you see for your test may use a swab to take a sample of it.
Results are usually available within a couple of weeks.
Treatment is usually by taking a single dose of antibiotics, followed by a second test around a week later to make sure it's worked.
You should avoid sex until you've been given the 'all clear'.
If you have a partner, they should be tested and treated at the same time.
To make sure you don't re-infect each other, avoid sex until you both test negative.