Halicephalobus, the deadly parasitic worm that is thought to have caused the death of two kidney transplant patients, has never been transferred between humans before, an inquest heard today.
The worm lives in soil, manure and compost and there have been only five known cases in humans - all of which were fatal - with another 30 to 40 cases in horses.
Once the worm is inside a host's body, it can multiply and invade tissues such as the brain, causing major swelling.
The cases involving Darren Hughes and Robert Stuart and their unidentified kidney donor are the first known occurrences in the UK.
If Hughes and Stuart's deaths were transferred by the donor's organ, they would be the first human-to-human cases ever known, Cardiff Coroner's Court was told.
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