As treatment adult and larvae may be removed mechanically by rinsing the conjunctival sac with sterilised saline and fluids or by picking them out with a fine forceps or cotton swab. In the latter case, local anaesthesia is recommended for detection and recovery (Shen et al., 2006). The symptoms generally resolve quickly after successful treatment.
Apart from mechanical removal, a local therapy with moxidectin (1-2 drops of an aqueous 1 % solution, approximately 0.006 mg) eliminated the worm burden in 48 dogs (30 of those showing clinical signs) within 2 min (Lia et al., 2004). The topical instillation of organophosphates has also proven to be highly effective against T. callipaeda (Rossi and Peruccio, 1989). A single spot-on application of moxidectin (2.5 %) plus imidacloprid (10 %) was effective for the control of thelaziosis in 21 dogs within 5 (90 %) to 9 days (95 %) (Biancardi and Otranto, 2005). Thus problems linked to mechanical removal of worms or restraining of dogs for topical treatment can be overcome. Injectable sustained-release formulation of moxidectin provided one season of protection against T. callipaeda infection in dogs (Rossi et al., 2007).
The systemic or local chemotherapy is preferable in comparison to a mechanical removal. And the sustained-release formulation is more likely expected to reduce the prevalence of dog thelaziosis and thus also the potential zoonotic risk in endemic areas (Otranto, 2008).
- Bianciardi P, Otranto D: Treatment of dog thelaziosis caused by Thelazia callipaeda (Spirurida, Thelaziidae) using a topical formulation of imidacloprid 10% and moxidectin 2.5%. Vet Parasitol. 2005, 129, 89-93
- Lia RP, Traversa D, Agostini A, et al.: Field efficacy of moxidectin 1 per cent against Thelazia callipaeda in naturally infected dogs. Vet Rec. 2004, 154, 143-5 (comment in: Vet Rec. 2004, 154, 248)
- Otranto D: Thelazia callipaeda eyeworm: a”neglected” CVBD of human concern. Proc. 3rd Int. CVBD Symposium, 2008, 94-102
- Rossi L, Peruccio C: Thelaziosi oculare nel Cane: aspetti clinici e terapeutici. Veterinaria. 1989, 2, 47-50
- Rossi L, Rigano C, Tomio E, et al.: Use of sustained-release moxidectin to prevent eyeworm (Thelazia callipaeda) infection in dogs. Vet Rec. 2007, 161, 820-1
- Shen J, Gasser RB, Chu D, et al.: Human thelaziosis – a neglected parasitic disease of the eye. J Parasitol. 92, 2006, 872-5