A team of doctors at University Hospital of Saint-Etienne in France recently found that the source of an itchy eye reported by a gardener who turned up at their emergency department was due to the presence of maggot larvae on the cornea. The team has published a paper describing their diagnosis and treatment of the case in the New England Journal of Medicine.

Sheep bot flies are common in France—they got their name due to their tendency to lay eggs in the nostrils of sheep. Once deposited, the larvae wiggle their way to the sinuses, where they stay, feeding on mucus as they develop into maggots. After a few weeks, they drop out of the nose onto the ground, where they finish their maturation process and grow into adult flies. Prior research has shown that sometimes the female flies become confused and lay their eggs on the eyeballs of unsuspecting humans.

In this new case, the gardener had taken himself to the emergency department after experiencing what he described as feeling something enter his eye. He noted also that he had been working on his garden, which was close to a sheep and horse farm, when he felt something run into his right eye. After several hours of itching, he decided that the problem was not going to go away on its own, so he went to the emergency department seeking help.

After taking a close look, the doctors diagnosed the condition as external ophthalmomyiasis, which is infestation of the eye by fly larvae. They noted the presence of the larvae had resulted in conjunctival hyperemia (dilated blood vessels), but no evidence of abrasions due to the use of body spicules by the larvae. The researchers found over a dozen mobile larvae. The team took pictures and also made videos to capture the movement of the tiny creatures.

The doctors removed the larvae one by one using tiny tweezers and prescribed a round of antibiotics to prevent infection. Ten days later, the patient returned for a follow-up and was found not to have suffered from any eye damage or infections.

--Bob Yirka , Medical Xpress