A WOMAN who ran into a swarm of flies while she was out jogging ended up with parasitic worms living in her right eye.
The 68-year-old started to feel irritation in her right eye in March 2018, a month after running a trail in California's Carmel Valley.
She tried to rinse out her eye with water and pulled out two worms, which measured around half an inch long.
The woman, who has not been identified, then sought help from specialist doctor Richard Bradbury, who retrieved a third worm and sent it for tests.
Experts at the Centres for Disease Control and Prevention (CDC) revealed that the worms were Thelazia gulosa, which had only ever been recorded in a human once before.
Thelazia gulosa are found across Asia, Europe, North America and Australia.
Doctors don't know with certainty how the woman was infected by the creature, but their larvae normally live in the eyes of animals such as dogs, cows and horses.
The larvae are normally consumed by flies – but they survive being eaten – and are transferred from the insects to other animals when the flies land on them.
Symptoms of infection may include swelling, pain looking at light, excessively watery eyes or conjunctivitis.
The woman revealed that she spent time outdoors running and distinctly remembered a particular run in Carmel Valley in Feb 2018.
As she rounded a corner of a trail, she ran into a swarm of flies and “swatted the flies from her face and spat them out of her mouth”.
Her doctor told her to keep flushing her eye out with distilled water to remove any more worms and gave her a topical medication to prevent infection.
When she returned to Nebraska, where she lives, she still felt something was niggling in her eye but, despite several attempts, medics were unable to find any more worms.
The woman eventually pulled a fourth and final worm from her eye in her home, the report in the journal Clinical Infectious Diseases revealed.
The authors said humans may be “suitable hosts” for the reproduction of T. gulosa because they saw eggs developing in the woman's eye.
Abbey Beckley, 26, from Oregon, was the first known person to have had T. gulosa worms in her eye.
Three years ago, she felt something behind her eyelid while on a hike near Portland and initially thought it was a stray eyelash.
A total of 14 T. gulosa worms, all less than half an inch long, were extracted from Beckley's eye over the course of 20 days.
Having a second human case of T. gulosa occur within two years of the first case “suggest(s) this may represent an emerging zoonotic disease in the US,” the study authors wrote.
A zoonotic disease is one that jumps from animals to people, with children under five, adults over 65, and those with compromised immune systems being most at risk.
If the worms remain in a person's eye for a prolonged time, they can cause corneal scarring and even blindness, according to the researchers. --Daily Mail