A Case Report on Eye Worm, Thelazia callipaeda, in an Elderly Person in Nepal

Thelaziasis is a zoonotic disease caused by a nematode of genus Thelazia. Dogs, rabbits, cattle, and human are the definitive hosts, while flies act as an intermediate host. Human thelaziasis is reported occasionally from various geographic regions around the globe. There are several species of Thelazia, but Thelazia callipaeda is the most common to infect human. An 83-year-old man from a hilly rural region of Nepal who came for his routine glaucoma follow-up was found to harbor six eye worms in the conjunctival fornices. After mechanical removal under topical anesthesia, the worms were studied under light microscope. They appeared creamy/white in color, ranging from 9 to 12 mm in length, and had tapering ends. Based on morphometrics, they were identified as Thelazia callipaeda. This is the second case reported from the country. People of rural areas who live in close contact with domestic animals and in unhygienic conditions are at greater risk of human thelaziasis. The concerned authorities and the community should be alerted if eye worms are noticed in domestic animals and humans. These worms need to be identified and reported in the health care system to determine its prevalence and endemicity and to take necessary actions.