Doctors are warning that the popularity of sushi is fueling a rise in potentially deadly parasitic worm infections.
The Japanese cuisine is considered so dangerous because raw fish sometimes carry miniscule worms that bury themselves in the human gut if accidentally consumed.
The resulting condition – anisakiasis – can cause severe stomach pain, vomiting and fever.
In the latest such case, a healthy 32-year-old Portuguese man was left in excruciating pain for a week after eating raw fish from a Japanese restaurant. After checking his body via an endoscopy, doctors found a large number of white larvae burrowing into his gut lining. Medics had to use a special retrieval net to ‘catch’ the worms.
The man made a full recovery but, in severe cases, death can occur because of an anaphylactic reaction, with the parasites triggering an erratic heartbeat and respiratory failure.
BMJ Case Reports this week published an article citing the advice of the Lisbon doctors who treated the Portuguese victim, and warned other clinicians to consider whether sushi might be responsible for any patient admitted to hospital with pain, nausea, vomiting, bowel obstruction and bleeding.
Dr Joana Carmo, a gastroenterologist at the Hospital of Egas Moniz in Lisbon, told the Daily Telegraph in London: “Owing to changes in food habits, anisakiasis is a growing disease in Western countries, which should be suspected in patients with a history of ingestion of raw or uncooked fish.
“Patients can have allergic symptoms. Gastrointestinal symptoms include abdominal pain, nausea and vomiting and complications like digestive bleeding, bowel obstruction, perforation and peritonitis can also arise.”