Faecal-oral (usually contaminated water): infection by ingestion of 4-nucleated cysts.
Humans are the only reservoir
10% world population are infected (rare in temperate climates)
Cyst is digested in gut releasing trophozoites (active parasites) which can colonise and invade colonic mucosa and cause cell lysis and ulcerations. Trophozoites may remain in the bowel or invade extra-intestinal tissues leaving ‘flask-shaped ulcers’. Cysts pass in the stools of carriers indefinitely and are viable for up to 2 months.
Dr Tom Leach MBChB DCH EMCert(ACEM) currently works as a GP Registrar and an Emergency Department CMO in Australia. He is also a Clinical Associate Lecturer at the Australian National University. After graduating from his medical degree at the University of Manchester in 2011, Tom completed his Foundation Training at Bolton Royal Hospital, before moving to Australia in 2013. He started almostadoctor whilst a third year medical student in 2009.
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