Trichomonas infection - including symptoms, treatment and prevention

Trichomonas is an infection of the genital tract in both men and women is caused by a parasite called Trichomonas vaginalis.

How Trichomonia is spread

Trichomonia infection is a sexually transmitted infection (STI). Re-infection appears to be common.

Signs and symptoms of Trichomonia infection

In women, symptoms of trichomoniasis may include:

  • frothy yellow/green vaginal discharge which may have a foul odour
  • pain or discomfort during sexual intercourse
  • pain or discomfort when passing urine
  • low abdominal discomfort
  • there may be no symptoms.

In men, most infections are without symptoms, but some men have:

  • pain or discomfort when passing urine
  • epididymitis (inflammation of the storage tubes for sperm that are on top of the testes).

Having a current sexually transmitted infection (including Trichomonas infection) increases the risk of getting human immunodeficiency virus (HIV) infection if you are exposed to HIV.

Diagnosis of Trichomonia infection

Diagnosis is made by microscopic examination or culture of discharge from the vagina or penis.

Incubation period

(time between becoming infected and developing symptoms)

4 to 28 days, average 7 days, but symptoms may not develop.

Infectious period

(time during which an infected person can infect others)

The duration of the infection, which may last for years. People with infections but who have no symptoms are still able to transmit the infection to others.

Treatment for  Trichomonia infection

Treatment may be a single oral dose of an antibiotic, or may require a longer course of treatment. Pregnant women may be advised to use pessaries (tablets inserted into the vagina), as the oral drug is best avoided, if possible, during pregnancy.

Prevention of Trichomonia infection

  • Practise safer sex.
  • No sex until antibiotic treatment is completed and your usual sexual partner has completed treatment.
  • All sexual partners need to be contacted, tested and treated, if indicated. Even if partners have no symptoms they may be able to transmit infection to other sexual partners.
  • Testing to exclude other sexually transmitted infections is advisable.

Useful links