This is a schistosome, a parasitic flatworm that infects more than 200 million people worldwide, causing a debilitating disease called schistosomiasis. Adult worms spend their lives bathed in blood in the veins of the bladder or intestine. In a recent study scientists have shed light on the schistosome’s complex feeding habits, which could have major implications for developing drugs against them. The study shows that even within the weird world of worm parasites, schistosomes are odd. Unlike other worm parasites, they take up food in two ways. They either ‘feed’ by absorbing nutrients directly across the body surface (here, dyed green) or by drinking up blood through a mouth. Stranger still, they don’t have a bottom, or to use scientific speak, ‘schistosomes lack an anus.’ So as they lap up human blood with vampiric zeal, they later vomit up a toxic substance called heme that accumulates in their gut.
Written by Nick Kennedy
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