What is trichomoniasis?

Trichomoniasis is a sexually transmitted infection caused by a very small parasite, Trichomonas vaginalis, often called 'trich' (pronounced 'trike') for short. Worldwide, it is one of the commonest sexually transmitted infections (STIs), but it is uncommon in New Zealand.

The infection is most commonly diagnosed in sexually active females between 16 and 35 years. It is caught during sexual contact with an infected person. It can be passed by using sex toys, eg, vibrators.

How do I know if I have trichomoniasis?

Symptoms usually develop one to four weeks after contact with an infected person.

Symptoms in women can include:

• a copious, greenish, frothy, watery vaginal discharge with an unpleasant 'fishy' smell
• the opening to the vagina and vulva can be uncomfortable, hot or swollen with redness and inflammation that can extend onto the upper thighs. This can lead to discomfort when walking
• itching or pain when passing urine can also occur
• mamy women are infected without symptoms.

Symptoms in men can include:

• some men may experience a discharge from the penis and discomfort when passing urine
• sometimes it produces an inflammation of the head of the penis (balanitis)
• however, usually most men do not have symptoms and act as carriers of the infection.  

How is it diagnosed?

Examination of the vagina is required and a swab of the vaginal fluid can be sent to a laboratory where the organism can be detected by culture or other methods. Most sexual health clinics will be able to examine a drop of vaginal fluid under a microscope and see the organism in the discharge, to make an instant diagnosis.

Trichomoniasis is very difficult to identify and diagnose in males. It can be found in urethral swabs or in urine specimens. Male partners of female patients with trichomonas always need to be treated, even if there are no symptoms.

Is there any long term damage?

As far as is known, trichomoniasis does not cause any long term damage to internal organs and does not produce pelvic inflammatory disease. A few women, however, suffer from the infection even after their sexual partners have been treated. For those with persistent infection, an assessment by a sexual health specialist is advised.

How is it treated?

Treatment is with antibiotic tablets which can be given either as a single dose or as a seven-day course. It has about a 90% cure rate. Treatment sometimes causes mild nausea or an upset stomach. You can reduce these side effects by taking the tablets with food. Avoid alcohol during treatment and for 24 hours afterwards, or a severe hangover may result.

Some people experience an unpleasant taste in the mouth when taking the medication. This disappears soon after the treatment is completed.

Where should I go for treatment?

Sexual health clinics specialise in screening and treating all sexually transmitted infections. They offer a free and confidential service. Your family doctor and Family Planning Clinics are also able to treat trichonomiasis and other STIs.

Original material provided by Auckland Sexual Health Service. Reviewed by everybody in May 2008.