An anonymous reader quotes a report from Ars Technica:

A neurosurgeon in Australia pulled a wriggling 3-inch roundworm from the brain of a 64-year-old woman last year — which was quite the surprise to the woman’s team of doctors and infectious disease experts, who had spent over a year trying to identify the cause of her recurring and varied symptoms. A close study of the extracted worm made clear why the diagnosis was so hard to pin down: the roundworm was one known to infect snakes — specifically carpet pythons endemic to the area where the woman lived — as well as the pythons’ mammalian prey. The woman is thought to be the first reported human to ever have an infection with this snake-adapted worm, and it is the first time the worm has been found burrowing through a mammalian brain. […]

Subsequent examination determined the roundworm was Ophidascaris robertsi based on its red color and morphological features. Genetic testing confirmed the identification. The woman went on ivermectin again and another anti-parasitic drug, albendazole. Months later, her lung and liver lesions improved, and her neuropsychiatric symptoms persisted but were improved. The doctors believe the woman became infected after foraging for warrigal greens (aka New Zealand spinach) around a lake near her home that was inhabited by carpet pythons. Usually, O. robertsi adults inhabit the snakes’ esophagus and stomach and release their eggs in the snakes’ feces. From there, the eggs are picked up by small mammals that the snakes feed upon. The larvae develop and establish in the small mammals, growing quite long despite the small size of the animals, and the worm’s life cycle is complete when the snake eats the infected prey.

Doctors hypothesize the woman picked up the eggs meant for small mammals as she foraged, ingesting them either by not fully washing or cooking the greens or by not properly washing her hands or kitchen equipment. In retrospect, the progression of her symptoms suggests an initial foodborne infection, followed by worm larva migrating from her gastrointestinal tract to multiple organs. The prednisolone, an immunosuppressive drug, may have inadvertently helped the worm migrate and get into the central nervous system. Kennedy, a co-author of the report on the woman’s case, stressed the importance of washing any foods foraged or taken from a garden. She also emphasized proper kitchen safety and hand washing.

Originally Posted at