False-colour transmission electron micrograph of the parasitic protozoan Trichomonas vaginalis. The pear-shaped organism is 15-20 microns in length with four flagella arising from its blunt end & an undulating membrane down one side (left). It infects the genito-urinary tracts of both sexes: in men this is usually symptomless, but in women vaginal infection may cause severe irritation & a foul-smelling discharge. T. vaginalis cannot survive at the pH level of the healthy vagina and probably depends upon a disturbance of the normal flora for establishment there. Transmission is commonly, but not exclusively, by sexual inter- course. Mag: x2,800 at 6x4cm, x1,600 at 35mm size.
Model release not required. Property release not required.