PetCaseFinder

Peer-reviewed veterinary case report

Dog eye worm infection confirmed in India with eye discharge and ulcer

By Marak, Alayda N et al.·Published in Veterinary ophthalmology·2026·Department of Veterinary Medicine, India·View original on PubMed

PetCaseFinder translated the abstract of this peer-reviewed paper into plain English so pet owners can read it. We do not publish original research — every detail traces back to the citation above. How we work →

Original publication title: First Molecular Confirmation of Canine Ocular Thelaziosis Caused by Thelazia callipaeda From India.

Species:
dog

Plain-English summary

An 8-year-old male mixed-breed dog had a two-week history of a runny eye, redness, and irritation in the right eye. Upon examination, the veterinarian found multiple small worms in the eye, which were identified as Thelazia callipaeda, a type of parasitic worm. The treatment involved removing the worms, giving the dog ivermectin, and providing supportive eye care. After following this treatment plan, the dog recovered well, and the case highlights the importance of being aware of this emerging eye parasite in dogs.

People also search for: dog eye discharge treatment · dog conjunctivitis causes · Thelazia callipaeda in dogs

Abstract

OBJECTIVE: To confirm and characterize Thelazia callipaeda infection in a dog using morphological and molecular tools, analyze its phylogenetic relationship with isolates from other regions, and evaluate the clinical and therapeutic outcomes. ANIMALS STUDIED: An 8-year-old male mixed-breed dog with a 2-week history of unilateral mucopurulent discharge, epiphora, conjunctivitis, and corneal ulceration in the right eye. PROCEDURES: Ophthalmic examination revealed multiple thread-like worms in the affected eye. Worms were preserved in 70% ethanol, and genomic DNA was extracted for molecular analysis. A 689 base pair fragment of the mitochondrial cytochrome c oxidase subunit 1 (cox1) gene was amplified via polymerase chain reaction, sequenced, and analyzed using Basic Local Alignment Search Tool and Molecular Evolutionary Genetics Analysis (Maximum Likelihood method, 1000 bootstrap replicates) software. Therapeutic management included mechanical removal, systemic ivermectin, and supportive topical therapy, with follow-ups until recovery. RESULTS: The dog exhibited ocular irritation, lacrimation, and conjunctival hyperemia. Morphological features confirmed T. callipaeda (distinct buccal capsule, cuticular striations, and encysted larvae in the anterior end of the female worm). The cox1 gene sequence showed 99.4% similarity with isolates from Slovakia and China, with nucleotide substitutions at positions 298 (Cysteine→Threonine), 339 (Alanine→Glycine), 342 (Threonine→Cysteine), and 348 (Glycine→Alanine). Phylogenetic analysis clustered the isolate with European and Asian lineages. CONCLUSION: This report describes the first molecularly confirmed report of T. callipaeda infection from India, emphasizing the need for increased awareness and regional surveillance of this emerging zoonotic parasite.

Find similar cases for your pet

PetCaseFinder finds other peer-reviewed reports of pets with the same symptoms, plus a plain-English summary of what was tried across them.

Search related cases →

Original publication on PubMed: https://pubmed.ncbi.nlm.nih.gov/41777076/