Eyeworm Infection (Thelaziosis) in a Dog: A New Threat for Dogs in Turkey

Abstract

Introduction: Canine thelaziosis caused by Thelazia callipaeda also referred to as ‘the oriental eye worm’ is increasingly common in Europe and infects dogs, cats, foxes, rabbits, and humans. Adult T callipaeda reside in the eyes and associated tissues. infected animals show a variety of clinical presentations, from subclinical carriage through to mild (eg, epiphora, conjunctivitis and chemosis) and severe pathology including corneal ulceration. Case: A 15 months-old male Sıvas Kangal (50 kg) suffering from redness and conjunctivitis of both eyes presented to Clubvet/Istanbul on August 13, 2019. On clinical examination worms were detected on the conjunctiva of both eyes. Following sedation with xylasine intravenously (1 mg/kg body weight Rompun %2, 25 ml, Bayer) approximately 100 nematodes were manually recovered from beneath the nictitating membrane and conjunctival sac. Irrigation with %2-3 boric acid had been applied. Five nematodes were placed in a 10 per cent formalin solution and submitted to Merkez Lab for identification. A dose of 0.6 mg/kg of Ivermectin given subcutaneously (Avromec, Topkim), weekly for 3 weeks. A course of topical ofloxacin, one drop four times daily, (Exocin % 0.3 eye drops 5 ml, Allergan) and hyaluronic acid, one drop four times daily and oral meloxicam once daily (Boehringer) was prescribed and continued for a further seven days. Re-examination on 21 days post-treatment showed a significant improvement in ocular comfort with a regular blink rate and lack of ocular discharge. No further worms were identified by examination or flushing of the eyes or nasolacrimal ducts. No further problems have been reported since. In conclusion, this canine ocular thelaziosis demonstrate the potential risks posed to the canine population in Turkey from infection with T callipaeda. Although effective diagnostic tests and treatments are available, more should be done to prevent this zoonotic pathogen from becoming endemic in Turkey.