Table 2 Ocular tissue affected and symptoms caused by zoonotic helminths (Genus and/or Species) at different stage [41, 63].

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