Background: Thelaziasis is a zoonotic disease mainly caused by Thelazia callipaeda (Spirurida, Thelaziidae, Thelazia), which can cause mild to severe signs and lesions, such as foreign body sensation, itching, tearing, eye pain, conjunctival bleeding, conjunctivitis, corneal ulcers, and even blindness. Besides, thelaziasis is mainly prevalent in areas with poor economic and health conditions and a large number of local domestic or wild animals infected, especially in summer and autumn.
Case presentation: A 41-year-old office lady presented to the hospital and reported itching in her right eye for one month in Beijing. This patient had a history of seasonal allergy and owned a cat and once found cat fur on her contact lens before the itching onset. Four worms were observed in the superior conjunctival sac of her right eye. The worms were removed and identified as Thelazia callipaeda. The symptoms resolved after the removal of the worms. Then, The patient received gatifloxacin ointment for one week. There were no recurrences at the 2-month follow-up.Conclusion: We report a case of human thelaziasis in Beijing. Though most previous cases were from rural areas with poor sanitation, doctors should be aware of the possibility of this disease in the city. In our report, several clinical signs were discussed as indications for the diagnosis, which may lead to faster identification of thelaziasis and earlier treatment initiation

Shumei Tan, born in 2000, entered Clinical Medicine (Eight-year program) at Peking University Health Science Center in 2018. In 2023, she entered the Department of Ophthalmology of Peking University Third Hospital to study for Doctor of Medicine. At present, she has published an ophthalmological SCI article as the first co-author (IF=2.1).