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Table 1 Classification (Order, Family and Species) of zoonotic helminths causing human blindness divided according their route of transmission (Vector borne zoonosis, VbZ, food consumption, FbZ, and those at direct transmission from the environment, EbZ), geographical distribution, localization in the eyes and zoonotic relevance.

From: Zoonotic helminths affecting the human eye

OrderOrder (Family) Species (common name) Route of transmission Geographical distribution Localization Definitive host REF
  Angiostrongylus cantonensis (rat lungworm) Ingestion of snails, slugs, shellfish and crustacean (FbZ) Asia, Australia, Africa, USA, Pacific Islands, Caribbean Islands, and South America Anterior chamber, vitreous Rat 131,137
Ascaridida (Ascarididae)       
  Toxocara canis (dog roundworm) Dog faeces (EbZ) Worldwide Eyebrows and eyelds, aqueous humor and vitreous Dog 11
  Toxocara cati (feline roundworm) Cat faeces (EbZ) Worldwide Aqueous humor and vitreous Cat 11
  Baylisascaris procyonis (raccoon roundworm) Raccoon faeces (EbZ) North America, Europe, Japan Vitreous Raccoon 46
Spirurida Suborder Spirurina       
  Gnathostoma spinigerum, G. hispidum, Ingestion of crustacean (cyclops), Worldwide Anterior chamber, eye lid Dog, cat, wild carnivores, 49
  G. doloresi and G. nipponicum infected fish, frogs (FbZ)    raccoon, opossum  
  Dirofilaria repens Aedes, Anopheles, Culex (VbZ) Europe, Asia, Africa Subconjunctival Dog 8, 197
  D. immitis Aedes, Anopheles, Culex (VbZ) Worldwide Anterior chamber Dog, cat 8,76
  D. tenuis Aedes, Anopheles, (VbZ) Canada, USA Subconjunctival Raccon 8
  Acanthocheilonema arbuta Aedes, Taeniorhynchus (VbZ) Canada, USA Anterior chamber Porcupine 198
  A. sprenti Mosquitoes (VbZ) Canada, Oregon, USA Anterior chamber Beaver 8
  A. reconditum Fleas, louses (VbZ) Worldwide Subconjunctival Dog 79
  Onchocerca gutturosa Simulium spp. (VbZ) Worldwide Subconjunctival, cornea Cattle 8
  O. cervicalis Culicoides spp. (VbZ) Worldwide Subconjunctival, cornea Horse 169
  Onchocerca jakutensis Culicoides spp. (VbZ) Europe, Austria Subconjunctival, cornea Red deer 199
  O. reticulata Culicoides spp. (VbZ) Europe, Asia, Africa Subconjunctival, cornea Horse 170
  O. dewittei japonica Simulium spp. (VbZ) Japan Subconjunctival, cornea Bear 167
  O. lupi Simulium spp. (VbZ) Europe Subconjunctival Dog 172
  Loaina uniformis Aedes, Anopheles, Culex North America Subconjunctival Lagomorphs 8,62,64,83
  P. (Loaina) scapiceps Aedes, Mansonia North America Subconjunctival Lagomorphs 8,62,83
  Thelazia callipaeda T. californiensis Phortica spp. (VbZ) China, Southeastern Asia, Europe, USA Subconjunctival, intraocular Dogs, cats, rabbits and wild carnivores 160
(Trichuridae) Trichinella spp. Ingestion of raw meat (FbZ) Worldwide Orbit, Ocular muscles Numerous, domestic and wild animals 15
Pseudophyllidea (Diphyllobothriidae)       
  Spirometra erinaceieuropaei (Sparganosis) Ingestion of crustacean, frogs, birds, snakes (FbZ) Middle East, Australia Subconjunctival Carnivores 102,109
  Spargana (other species) Ingestion of crustacean, frogs, birds, snakes (FbZ) South America, Asia Subconjunctival Carnivores 102,109
Cyclophyllidea (Teniidae)       
  Taenia crassiceps Food contaminated by dog faeces (EbZ) USA and Europe Anterior
Carnivores 89
  Echinococcus granulosus Food contaminated by dog faeces (EbZ) Worldwide Intraocular Dog 112
  E. multilocularis Food contaminated by wild carnivores dog faeces (EbZ) Worldwide Intraocular Wolf, jackal, coyote 115
  E. oligharthrus Food contaminated by wild carnivores dog faeces (EbZ) South and Central America Orbit Wild felids Wild felids
  Coenurus cerebralis (Multiceps multiceps) dog faeces (EbZ) Worldwide Intraocular Dog 95
  Fasciola hepatica water plants (FbZ) Worldwide Anterior chamber Domestic and wild ruminants, horse 120
  Alaria mesocercaria, A. americana Frogs (FbZ) Asia, USA, Canada Intraocular Canids 122
  Philophthalmus lacrimosus Contaminated food or direct contact with the eye mucosa (EbZ) Europe, Asia, and America Conjunctival Birds 124