Table 2 Ocular tissue affected and symptoms caused by zoonotic helminths (Genus and/or Species) at different stage [41, 63].
| Ocular tissue affected | Signs | Helminths involved |
|---|---|---|
| Eyebrows and eyelids | Eye lid edema | Taenia solium (cysticercus), Spirometra, Ancyclostoma, A. Americana Gnathostoma, Toxocara, Trichinella, Dirofilaria |
| Lacrimal duts and glands | Lacrymation | Mammomonogamus, Thelazia |
| Orbit | Exophthalmos | Echinococcus, coenurus, Taenia solium (cysticercus), spargana, Trichinella, Dirofilaria, Gnathostoma |
| Ocular muscles | Diplopia |
Trichinella, Angiostrongylus, Ancyclostoma, spargana, Taenia |
| Conjunctiva | Subconjunctival cysts | Taenia, Dirofilaria, Acanthocheilonema, Habronema, Mansonella, spargana, Philophthalmus |
| Chemosis and conjunctivitis | Thelazia, Trichinella, Onchocerca | |
| Hemorrhages | Trichinella | |
| Cornea | Keratitis, scleritis | Onchocerca, Toxocara, Ancylostoma |
| Anterior chamber | Parasites in the anterior Chamber | Onchocerca, Schistosoma, Taenia, spargana, Angiostrongylus, Gnathostoma, Toxocara, Dirofilaria, Thelazia, Acanthocheilonema |
| Cysts in the anterior chamber | Taenia | |
| Hypopyon | Taenia, Gnathostoma, Toxocara | |
| Secondary glaucoma | Taenia, Echinococcus, Angiostrongylus, Dirofilaria, Onchocerca spp., Gnathostoma, Toxocara | |
| Iris | Mydriasis | Trichinella |
| Miosis | ||
| Distortion of the pupil | Onchocerca | |
| Iritis and iridocyclitis | Taenia, Angiostrongylus, Ancyclostoma, Trichinella Toxocara, Onchocerca, Pelecitus | |
| Vitreous body | Hemorrhages | Trichinella, cysticercus, Gnathostoma |
| Cysts | Cysticercus, Echinococcus, coenurus | |
| Parasites in the vitreous Cyclitis | spargana, Acanthocheilonema, Dirofilaria, Onchocerca Gnathostoma, Onchocerca, Toxocara, Trichinella | |
| Optic nerve | Papilledema, papillitis, and optic atrophy | Taenia, Ancylostyoma, Toxocyara, Trichinella, Onchocerca |
| Retina and chorioidea | Hemorrhages | Ancylostoma, Gnathostoma, Toxocara, Trichinella |
| Retinal detachment | Taenia | |
| Cysts | Echinococcus | |
| Retinitis and choroiditis | Baylisascaris, Taenia, Toxocara, Trichinella, Onchocerca |