Schistosomiasis.

An estimated 200 million people and many more domestic animals throughout the tropical and sub-tropical world suffer from the parasitic disease schistosomiasis (also known as bilharzia), while more than 400 million others are at risk of infection. With the aid of cinemicrography, electron micrographs and graphics, this video gives a highly detailed account of each stage in the life-cycle of 'Schistosoma mansoni', one of the five principal species of schistosome and shows how certain characteristic features of the life-cycle of schistosomes help explain the failure to devise any effective vaccine against human schistosomiasis to date.