Experts believe the woman became an "accidental host" to the parasite when she was foraging for greens near a lake by her home.
A woman in Australia was hospitalized after experiencing a litany of strange symptoms, which started with stomach pain, coughing, and night sweats and escalated to cognitive conditions — but no one expected that the source of these mystery symptoms would turn out to be a small, three-inch-long worm.
“It was definitely not what we were expecting. Everyone was shocked,” operating surgeon Dr. Hari Priya Bandi told the BBC.
The 64-year-old woman had suffered from her initial symptoms for nearly three weeks before first entering the hospital in January 2021. At first, she experienced abdominal pain, diarrhea, a constant dry cough, a fever, and night sweats.
A brain scan later revealed that she had “an atypical lesion within the right frontal lobe of the brain.”
Still, the true cause of her symptoms remained elusive — and it wouldn’t be until June 2022, after the woman’s symptoms had evolved to include forgetfulness and depression, that Bandi would make a startling discovery.
The woman had been referred to Canberra Hospital, where she was given an MRI that revealed abnormalities in her brain requiring surgery.
But as Bandi’s colleague, infectious disease physician Dr. Sanjaya Senanayake, told The Guardian, “the neurosurgeon certainly didn’t go in there thinking they would find a wriggling worm… this was a once-in-a-career finding. No one was expecting to find that.”
Bandi said the operation had only just started when she felt something odd in the part of the brain that showed up strangely in the scans.
“I thought, gosh, that feels funny, you couldn’t see anything more abnormal,” Bandi said. “And then I was able to really feel something, and I took my tweezers and I pulled it out and I thought, ‘Gosh! What is that? It’s moving!'”
Bandi said the worm was “happily moving, quite vigorously, outside the brain.”
Unsure of what to do with this new and strange discovery, Bandi consulted Senanayake.
“We just went for the textbooks, looking up all the different types of roundworm that could cause neurological invasion and disease,” Senanayake said. Unfortunately, the resources at their disposal yielded no fruitful results, and they were forced to contact outside experts.
“Canberra is a small place, so we sent the worm, which was still alive, straight to the laboratory of a CSIRO scientist who is very experienced with parasites,” Senanayake said. “He just looked at it and said, ‘Oh my goodness, this is Ophidascaris robertsi.'”
Ophidascaris robertsi is a relatively common roundworm found in carpet pythons — nonvenomous snakes located across Australia. But the Canberra hospital patient is the first time this worm has been seen in a human.
Experts believe that the woman became an “accidental host” after collecting Warrigal greens, a type of native grass, from a lakeside near her home to use in cooking. Carpet pythons also inhabit the area, and the leading hypothesis among experts is that a python shed the parasite via its feces into the grass.
So, despite no direct contact with the python, the woman may have become infected with the parasite when she touched the grass — either from later transferring it to other food or from eating the grass itself.
Senanayake noted that treatment was difficult for the patient, as even after the worm in her brain was removed, they had to treat her for any other parasite larvae that could be in her system. However, some medications that kill off larvae can also cause inflammation, which can harm organs such as the brain.
“That poor patient, she was so courageous and wonderful,” Senanayake said. “You don’t want to be the first patient in the world with a roundworm found in pythons and we really take our hats off to her. She’s been wonderful.”
Senanayake added that the patient is recovering well and is still being regularly monitored. Researchers are also working to determine if a pre-existing condition that caused the woman to be immunocompromised could have made it easier for the larvae to get a foothold.
This strange case also adds to an already growing and concerning trend of infections spreading from animals to humans.
“There have been about 30 new infections in the world in the last 30 years,” Senanayake said. “Of the emerging infections globally, about 75 percent are zoonotic, meaning there has been transmission from the animal world to the human world. This includes coronaviruses.”
Fortunately, this specific infection is not transmittable between people, Senanayake said, so there is no concern that it will turn into a pandemic like COVID-19 or Ebola.
That said, carpet pythons and the parasite that attaches to them are found in other parts of the globe — meaning the world could see this happen again sooner rather than later.
After reading about this strange parasite infection, read the equally strange case of Sam Ballard, the Australian teen who ate a slug on a drunken dare and died as a result. Or, read about the time a parasitic worm crawled up a man’s penis, laid eggs, and nearly killed him.