#Doctors pull 1.5-inch worm from woman’s tonsils after she ate sashimi

Sushi, poke and other similar dishes have gained a reputation as a risky food group, where even the most prized cuts can come with an unwelcome garnish: parasites.

By nature of their uncooked preparation, parasites that call many fish home can survive even while the fish is out of water and long-dead. Sometimes just a few millimeters long, these worms can go unnoticed on the plate, and later wreak havoc on your insides.

On July 8, doctors in Tokyo reported the case of an anonymous 25-year-old woman who was admitted to St. Luke’s International Hospital over a sore throat earlier this year. A simple examination revealed “a black moving worm” wriggling in her left palatine tonsil, determined to be a Pseudoterranova azarasi, a type of parasitic roundworm.

In their study, published in the American Journal of Tropical Medicine and Hygiene, they noted that the woman had consumed a meal of “assorted sashimi” five days prior, and had suffered a sore throat ever since. That’s how they determined that sushi was to blame.

They wrote that her “symptoms rapidly improved” after a tweezer-removal. They measured the worm at 38 millimeters (1.5 inches) long and a millimeter wide, and noted that it was “molting the outer cuticle,” which “revealed this worm was a fourth-stage larva of Pseudoterranova azarasi.”

The Pseudoterranova genus of nematode is rarely known to infect the digestive tract, including the throat, where it causes pain, cough and “tingling throat syndrome.” However, usually these parasites settle in the stomach, leading to abdominal discomfort, and usually requires an endoscopy to remove.

There have been hundreds of cases of Pseudoterranova infection around the world, according to their research, which were usually remedied upon removal.

A recent study in the journal Global Change Biology found that “sushi parasites” are on the rise. They noted a 283-fold spike in the amount of Anisakis, another genus of worm found in raw fish, between 1967 and 2017. Study authors called for more meticulous inspection, and further study on the disconcerting trend, which could threaten marine animal populations.

“At every stage of seafood processing and sushi preparation, people are good at finding worms and removing them from fish,” said Chelsea Wood, assistant professor at the University of Washington School of Aquatic and Fishery Sciences.

She continued, “It’s not often considered that parasites might be the reason that some marine mammal populations are failing to bounce back. I hope this study encourages people to look at intestinal parasites as a potential cap on the population growth of endangered and threatened marine mammals.”