Woman Discovers ‘Worm-Like’ Parasite Living in Eye for Two Years

A worm-like parasite lived in a woman’s eye for two years, and doctors believe it entered her body after she ate crocodile meat.

The infected 28-year-old woman, from the town of Basankusu in the Democratic Republic of the Congo, went to the doctor after developing a mass in the corner of her left eye. It turned out to be a living bug, which is related to a shrimp, nearly half an inch long.

According to a paper in the journal JAMA Ophthalmology, the parasite had grown to around 0.4 inches, and had embedded itself behind the eyelid. The woman’s condition is known as ocular pentastomiasis, named after the parasite, known as a pentastomid or tongue worm. And scientists linked it to the woman’s diet, which included crocodile meat.

“Pentastomids look worm-like, but are actually modified crustaceans, so they are related to shrimps,” study author Dennis Tappe told Newsweek. “They are associated with reptiles (most often snakes, but also lizards and crocodiles), less so with amphibians, which all form their natural hosts.”

“They live in the upper respiratory tract of these animals. Humans get infected by orally taking up ova from the parasites which are shed by reptiles into the environment by feces and oral secretions,” added Tappe, a parasite researcher at the Bernhard Nocht Institute for Tropical Medicine in Germany.

When doctors examined the patient, they found that the mass was alive. After extracting it, they discovered it was a pale C-shaped tongue worm larva.

“Pentastomiasis is a rare zoonotic disease (transmittable from animals to humans) caused by the larval stages of pentastomid parasites. Most human infections occur in the tropics and subtropics,” says the journal paper.

Tongue worms grow to between 0.4 and 5.5 inches long. Its eggs exit the host via its mouth or digestive system, where it may be eaten by a rodent, where the eggs hatch and develop into larvae. The rodent is then eaten by a snake, or other host and the cycle starts again.

No case of this type of infection has been reported in individuals who eat crocodile meat, but crocodiles can be infected by pentastomids, said the authors. “This meat could also have been contaminated via infected snake meat on a market stall,” they added.

When people are infected by these parasites, the tiny invaders often burrow into internal organs, but rarely cause symptoms. Occasionally, the parasites can cause organ perforations and immune reactions, and even sometimes death.

The infection of the woman’s eye is a rare place for these parasites to be found, the paper authors said, but it made it easier to diagnose and remove the larvae.

Removing the parasite from the body is usually the best course of treatment, as killing them with antiparasitic drugs can result in their dead bodies setting off an immune response in the body, according to the paper.

“Abdominal infections are the most abundant infections encountered, but still rare, and most often not symptomatic,” Tappe explained. “Eye infections, in contrast, are easily visible from the outside, are symptomatic, but particularly super rare.

Surgery

“Treatment is by surgery, i.e., surgical removal of these larval parasites from the eye. However, the eye often does not fully recover due to the damage done by the inflammation and scarring of eye tissue,” he said.

Preventive measures include sticking to hygiene practices, which include wearing gloves and washing hands after handling reptiles, as well as refraining from consuming undercooked reptile meat.

The extent of the woman’s recovery was not known to Newsweek at the time of publishing.

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