Woman has burning sensation in legs after vacation — then doctors find brain parasites

Miami Herald

21-02-2025

After a three-week-long vacation through Thailand, Japan and Hawaii, a 30-year-old woman learned she brought home an unwelcome souvenir, doctors said.
When the woman first returned home to the coast of New England, she felt fatigued and attributed it to jet lag from weeks of traveling, according to a Feb. 13 case report published in the New England Journal of Medicine.
Her lack of energy was accompanied by a slight burning sensation in her feet, according to the case report, and she took some ibuprofen to help alleviate the pain.
The medications were unsuccessful, and over the next eight days, the burning sensation spread up her body into her legs, doctors said.
The pain got worse when her legs were touched, according to the report, and she went to the emergency room.
Burning spreads to the chest
The woman went through a series of tests — she had a normal temperature, heart rate, blood pressure and blood oxygen saturation — and she was sent home with instructions to follow up with her primary care physician, doctors said.
But over the next three days, the burning feeling spread up to her chest and arms and she developed a headache that wouldn't wane even with over-the-counter pain medication, according to the report.
The woman went back to the emergency room, but again showed normal tests, so she was given intravenous pain medications that helped her still-pounding headache and was sent home with the same instructions, doctors said.
'After the patient arrived home from the emergency department, she took zolpidem ((a drug for insomnia) which had been prescribed for a family member) to help with sleep. On the day of the current presentation, confusion developed,' doctors said. 'In the morning when she awoke, she thought she needed to pack for vacation and was not redirectable when her roommate attempted to help her lie back down in bed. When confusion did not resolve after several hours, the patient's partner brought her to this hospital for further evaluation.'
Sushi, street food-filled vacation
Then, doctors learned more about her trip.
In Bangkok, Thailand, she toured the city and stopped for street food along the way, but said she didn't eat anything raw, according to the report. Her next stop was Tokyo, Japan, where she said she mainly stayed in the hotel, but ate sushi throughout her stay. The majority of her trip was spent in Hawaii swimming in the ocean and eating salads and sushi.
Her newly developed confusion led doctors to try new tests, including a lumbar puncture, a procedure that taps into the spine to test the cerebrospinal fluid, according to the report.
The fluid underwent a diagnostic test, and finally the woman had an answer — she had parasites in her brain.
Doctors discovered Angiostrongylus cantonensis, a parasitic species of roundworm also called rat lungworm.
An A. cantonensis infection can lead to human eosinophilic meningitis, which the woman was experiencing.
'Human infection, which was initially described in Taiwan, is now distributed across many tropical and subtropical regions in southeast Asia and the Pacific Islands (including Hawaii), with expanding distribution that now includes locally acquired infections in Europe, Australia, the southern United States and the Caribbean,' doctors said. 'Only five cases of angiostrongyliasis were confirmed in Hawaii in 2024; however, given that 9 to 10 million tourists visit Hawaii each year, many people may have been exposed to infection but may not have symptoms until after they leave Hawaii.'
The infection can come from a few sources: raw or undercooked snails or slugs, vegetables or fruit that have been contaminated by snails, slugs or flatworms or their slime, or by eating infected hosts like land crabs, freshwater prawns or frogs, doctors said.
It can take as many as 14 days after the parasites are ingested for symptoms to begin, according to the report.
Symptoms usually begin as headache, nausea, vomiting and fever, but then can spread to neurological symptoms after the parasite leaves the bloodstream, enters muscle, migrates to peripheral nerves and into the spinal column and brain, doctors said.
The woman was treated with a directed therapy of medications — albendazole, prednisone, gabapentin and amitriptyline — and her headache and burning sensation went away, doctors said. She was able to return home after six days in the hospital to recover.
The medical team includes Joseph Zunt, Amy K. Barczak and Daniel Y. Chang.