Trichomonas vaginalis (often known as ‘TV’) is a protozoan ‘bug’ that affects the vagina.

It causes a green or yellowish, bubbly vaginal discharge and intense vulval soreness. It also produces a ‘fishy’ smell.

However, some women have no symptoms at all, and men rarely do.

For unknown reasons, the incidence of ‘TV’ in the UK has declined sharply in recent years, though it is reported as still being common in the USA. Only about 6,000 cases were diagnosed in UK clinics last year. In addition, a substantial number were treated by GPs.