A Japanese woman who had eaten sashimi went to a hospital in Tokyo complaining of pain in the back of her throat… and got a horrifying surprise.
Doctors inspecting her throat saw a black, wriggling worm in her left tonsil – and warn infections could become more common as the taste for sushi spreads.
Doctors at St Luke's International Hospital in Tokyo extracted the worm from the woman’s throat with tweezers, Science Alert reported.
The creature was found to be a nematode roundworm – one of several parasites that are known dangers of eating sushi.
The doctors say the worm was a fourth-stage larva of a nematode worm, and the woman was infected from eating a third-stage larva in her raw fish.
The doctors write: “The worm body was black, 38 mm long, 1 mm wide, and was molting the outer cuticle. DNA PCR and the fact that the worm was in exuviation revealed this worm was a fourth-stage larva of Pseudoterranova azarasi.
“Pseudoterranova is an uncommon nematode of the family Anisakidae. Anisakis simplex, a major type of the family, is a white roundworm causing gastric, intestinal, ectopic, and allergic diseases.”
The doctors say infection in the throat is rare, but the worms more commonly infect people in the stomach.
Read more: Food poisoning ‘on the rise’ in the UK
The researchers write, “Just like Anisakis, Pseudoterranova infects dominantly in the stomach after consuming third-stage larvae in raw or undercooked marine fish, and more than 700 cases have been reported in Japan, North Pacific countries, South America, and the Netherlands.”
The researchers warn infections with the worm are set to become more likely as sushi and sashimi become more popular, and say throat infections with the worm can be identified due to throat tingling and cough.