Ocular Parasitic Infections

  • S. R. Rathinam
  • Yogish Kamath


Ocular parasitology is the study of parasites that infect humans and result in ocular complications. Complications occur either due to mechanical, immunologic, or allergic reactions [1]. Because of protean manifestations and lack of clinical suspicion, the diagnosis is often missed. Prior to making a final diagnosis, ophthalmologists have to get dietary history, as most parasitic transmission is through food and water contamination. Travel history to endemic areas is important to determine the source of infection. When the humans are not the definitive hosts, but play the role of an accidental or intermediate host, the parasites do not mature into adult worms. Eggs or cysts are seldom found on stool examination. It is important for the ophthalmologists to understand the life cycle of the worm to select proper diagnostic tests (Table 13.1). Construction of an algorithm regarding management of ocular parasites is mandatory (Fig. 13.1). Sometimes patient may have associated systemic infestation (Fig. 13.2a, b). Careful systemic examination can aid in comprehensive treatment. There are several agents that can affect different ocular structures; clinical signs depend on the location and type of organism (Table 13.2).


Intermediate Host Adult Worm Optic Neuritis Hydatid Cyst Definitive Host 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


Financial Support

Aravind Medical Research Foundation & Defense Research and Development Establishment (DRDE), Gwalior.


  1. 1.
    Otranto D, Eberhard ML. Zoonotic helminths affecting the human eye. Parasit Vectors. 2011;4:41.PubMedCentralCrossRefPubMedGoogle Scholar
  2. 2.
    Nimir AR, Saliem A, Ibrahim IAA. Ophthalmic parasitosis: a review article. Interdiscip Perspect Infect Dis. 2012;
  3. 3.
    Molyneux D, Hallaj Z, Keusch GT, et al. Zoonoses and marginalised infectious diseases of poverty: where do we stand? Parasit Vectors. 2011;4:106.PubMedCentralCrossRefPubMedGoogle Scholar
  4. 4.
    Rathinam SR, Ashok K. Ocular manifestations of systemic disease: ocular parasitosis. Curr Opin Ophthalmol. 2011;21:478–84.CrossRefGoogle Scholar
  5. 5.
    Sow S, de Vlas SJ, Mbaye A, et al. Low awareness of intestinal schistosomiasis in northern Senegal after 7 years of health education as part of intense control and research activities. Trop Med Int Health. 2003;8:744–9.CrossRefPubMedGoogle Scholar
  6. 6.
    Yirga D, Deribe K, Woldemichael K, et al. Factors associated with compliance with community directed treatment with ivermectin for onchocerciasis control in Southwestern Ethiopia. Parasit Vectors. 2010;3:48.PubMedCentralCrossRefPubMedGoogle Scholar
  7. 7.
    Rathinam SR. Treating uveitis in the developing world setting. Int Ophthalmol Clin. 2010;50:219–28.CrossRefPubMedGoogle Scholar
  8. 8.
    Rathinam SR, Annamalai R, Biswas J. Intraocular parasitic infections. OculImmunol Inflamm. 2011;19:327–36.Google Scholar
  9. 9.
    Pahuja S, Puranik C, Jelliti B, et al. Parasitic infections of the external eye. OculImmunol Inflamm. 2013;21:292–9.Google Scholar
  10. 10.
    Hom MM, Mastrota KM, Schachter SE. Demodex. Optom Vis Sci. 2013;90:e198–205.CrossRefPubMedGoogle Scholar
  11. 11.
    Filho PA, Hazarbassanov RM, Grisolia AB, et al. The efficacy of oral ivermectin for the treatment of chronic blepharitis in patients tested positive for Demodex spp. Br J Ophthalmol. 2011;95:893–5.CrossRefPubMedGoogle Scholar
  12. 12.
    Sucilathangam G1, Meenakshisundaram A, Hariramasubramanian S. External ophthalmomyiasis which was caused by sheep botfly (oestrus ovis) larva: a report of 10 cases. J Clin Diagn Res. 2013;7:539–42.Google Scholar
  13. 13.
    Abdellatif MZM, Elmazar HMF, Essa AB. Oestrus ovis as a cause of red eye in Aljabal Algharbi, Libya. Middle East Afr J Ophthalmol. 2011;18:305–8.PubMedCentralCrossRefPubMedGoogle Scholar
  14. 14.
    Vijayalekshmi S, Shukla H. Unilateral acute conjunctivitis due to Oestrus ovis in a veterinary doctor. J Nat Sci Biol Med. 2013;4:2283–30.CrossRefGoogle Scholar
  15. 15.
    Maurya RP, Mishra D, Bhushan P, et al. Orbital myiasis: due to invasion of larvae of flesh fly (wohlfahrtia magnifica) in a child; rare presentation. Case Rep Ophthalmol Med. 2012;2012:371498.PubMedCentralPubMedGoogle Scholar
  16. 16.
    Chiapella KJ. Verminous ophthalmia. West J Med. 1974;120:500.PubMedCentralPubMedGoogle Scholar
  17. 17.
    Otranto D, Traversa D. Thelaziaeyeworm: an original endo- and ecto-parasitic nematode. Trends Parasitol. 2005;21:1–4.CrossRefPubMedGoogle Scholar
  18. 18.
    Shen J, Gasser RB, Chu D, et al. Human thelaziosis – a neglected parasitic disease of the eye. J Parasitol. 2006;92:872–5.CrossRefPubMedGoogle Scholar
  19. 19.
    Sharma S, Pasricha G, Das D. Acanthamoeba keratitis in non-contact lens wearers in India: DNA typing-based validation and a simple detection assay. Arch Ophthalmol. 2004;122:1430–4.CrossRefPubMedGoogle Scholar
  20. 20.
    Corsi A, Nucci C, Knafelz D, et al. Ocular changes associated with Giardia lamblia infection in children. Br J Ophthalmol. 1998;2:59–562.CrossRefGoogle Scholar
  21. 21.
    Rippon JW, Varadi DP. The elastases of pathogenic fungi and actinomycetes. J Invest Dermatol. 1968;50:54–8.PubMedGoogle Scholar
  22. 22.
    Herr RA, Ajello L, Taylor JW. Phylogenetic analysis of Rhinosporidium seeberi’s 18S small-subunit ribosomal DNA groups this pathogen among members of the protoctistan Mesomycetozoa clade. J Clin Microbiol. 1999;37:2750–4.PubMedCentralPubMedGoogle Scholar
  23. 23.
    Morelli L, Polce M, Piscioli F, et al. Human nasal rhinosporidiosis: an Italian case report. Diagn Pathol. 2006;1:25.PubMedCentralCrossRefPubMedGoogle Scholar
  24. 24.
    Yokoi K, Goto H, Sakai JI, et al. Clinical features of ocular toxocariasis in Japan. OculImmunol Inflamm. 2003;11:269–75.Google Scholar
  25. 25.
    Rubinsky-Elefant G, Hirata CE, Yamamoto JH, et al. Human toxocariasis: diagnosis, worldwide seroprevalences and clinical expression of the systemic and ocular forms. Ann Trop Med Parasitol. 2010;104:3–23.CrossRefPubMedGoogle Scholar
  26. 26.
    Cortez RT, Ramirez G, Collet L. Ocular parasitic diseases: a review on toxocariasis and diffuse unilateral subacute neuroretinitis. J Pediatr Ophthalmol Strabismus. 2011;48(4):204–12.CrossRefPubMedGoogle Scholar
  27. 27.
    Gems D, Maizels RM. An abundantly expressed Mucin-like protein from Toxocara Canis Infective Larvae: the precursor of the larval surface coat glycoproteins. Proc Natl Acad Sci U S A. 1996;93:1665–70.PubMedCentralCrossRefPubMedGoogle Scholar
  28. 28.
    Tran VT, Lumbroso L, LeHoang P, et al. Ultrasound biomicroscopy in peripheral retinovitreal toxocariasis. Am J Ophthalmol. 1999;127:607–9.CrossRefPubMedGoogle Scholar
  29. 29.
    Wittenberg LA, Maberley DA, Patrick E, et al. Contribution of vitreous cytology to final clinical diagnosis. Ophthalmology. 2008;115:1944–50.CrossRefPubMedGoogle Scholar
  30. 30.
    Chieffi PP, Santos SV, Queiroz ML, et al. Human toxocariasis: contribution by Brazilian researchers. Rev Inst Med Trop Sao Paulo. 2009;51:301–8.CrossRefPubMedGoogle Scholar
  31. 31.
    Hotez PJ, Wilkins PP. Toxocariasis: America’s most common neglected infection of poverty and a helminthiasis of global importance. PLoS Negl Trop Dis. 2009;3:e400.PubMedCentralCrossRefPubMedGoogle Scholar
  32. 32.
    Barisani-Asenbauer T, Maca SM, Hauff W, et al. Treatment of ocular toxocariasis with albendazole. J Ocul Pharmacol Ther. 2001;17:287–94.CrossRefPubMedGoogle Scholar
  33. 33.
    Barrera MG, Leonardi D, Bolmaro RE, et al. In vivo evaluation of albendazole microspheres for the treatment of Toxocaracanis larva migrans. Eur J Pharm Biopharm. 2010;75:451–4.CrossRefPubMedGoogle Scholar
  34. 34.
    Taylor HR, Nutman TB. Onchocerciasis. In: Pepose JS, Holland GN, Wilhelmus KR, editors. Ocular infection and immunity. Mosby: St. Louis; 1996. p. 1481–504.Google Scholar
  35. 35.
    Ali MM, Baraka OZ, AbdelRahman SI, et al. Immune responses directed against microfilariae correlate with severity of clinical onchodermatitis and treatment history. J Infect Dis. 2003;187:714–7.CrossRefPubMedGoogle Scholar
  36. 36.
    Korten S, Kaifi JT, Büttner DW. Transforming growth factor-beta expression by host cells is elicited locally by the filarial nematode Onchocerca volvulus in hyporeactive patients independently from Wolbachia. Microbes Infect. 2010;12:555–64.CrossRefPubMedGoogle Scholar
  37. 37.
    Saint André A, Blackwell NM, Hall LR, et al. The role of endosymbiotic Wolbachia bacteria in the pathogenesis of river blindness. Science. 2002;295:1892–5.CrossRefPubMedGoogle Scholar
  38. 38.
    Taylor HR. Mazzotti test for onchocerciasis. Lancet. 1992;339:1549–50.CrossRefPubMedGoogle Scholar
  39. 39.
    Ozoh G, Boussinesq M, Bissek AZ, et al. Evaluation of the diethylcarbamazine patch to evaluate onchocerciasis endemicity in Central Africa. Trop Med Int Health. 2007;12:123–9.PubMedGoogle Scholar
  40. 40.
    Rodríguez-Pérez MA, Domínguez-Vázquez A, Méndez-Galván J, et al. Antibody detection tests for Onchocerca volvulus: comparison of the sensitivity of a cocktail of recombinant antigens used in the indirect enzyme-linked immunosorbent assay with a rapid-format antibody card test. Trans R Soc Trop Med Hyg. 2003;97:539–41.CrossRefPubMedGoogle Scholar
  41. 41.
    Ayong LS, Tume CB, Wembe FE, et al. Development and evaluation of an antigen detection dipstick assay for the diagnosis of human onchocerciasis. Trop Med Int Health. 2005;10:228–33.CrossRefPubMedGoogle Scholar
  42. 42.
    Boatin BA, Toé L, Alley ES, et al. Diagnostics in onchocerciasis: future challenges. Ann Trop Med Parasitol. 1998;92:S41–5.CrossRefPubMedGoogle Scholar
  43. 43.
    Taylor HR, Murphy RP, Newland HS, et al. Treatment of onchocerciasis. The ocular effects of ivermectin and diethylcarbamazine. Arch Ophthalmol. 1986;104:863–70.CrossRefPubMedGoogle Scholar
  44. 44.
    Lui L, Weller P. Antiparasitic drugs. N Engl J Med. 1996;334:1178–84.CrossRefGoogle Scholar
  45. 45.
    Hoerauf A, Specht S, Büttner M, et al. Wolbachia endobacteria depletion by doxycycline as antifilarial therapy has macrofilaricidal activity in onchocerciasis: a randomized placebo-controlled study. Med Microbiol Immunol. 2008;197:295–311.PubMedCentralCrossRefPubMedGoogle Scholar
  46. 46.
    Murdoch ME. Onchodermatitis. Curr Opin Infect Dis. 2010;23:124–31.CrossRefPubMedGoogle Scholar
  47. 47.
    Bhedasgaonkar S, Baile RB, Nadkarni S, et al. Loa loa macrofilariasis in the eyelid: case report of the first periocular subcutaneous manifestation in India. J Parasit Dis. 2011;35:230–1.PubMedCentralCrossRefPubMedGoogle Scholar
  48. 48.
    Bowler GS, Shah AN, Bye LA, et al. Ocular loiasis in London 2008–2009: a case series. Eye (Lond). 2011;25:389–91.CrossRefGoogle Scholar
  49. 49.
    Antinori S, Schifanella L, Million M, et al. Imported Loa loa filariasis: three cases and a review of cases reported in non-endemic countries in the past 25 years. Int J Infect Dis. 2012;16:e649–62.CrossRefPubMedGoogle Scholar
  50. 50.
    Passos RM, Barbosa CP, Almeida Jde S, et al. Subconjunctival Loa loa worm: first case report in Brazil. Arq Bras Oftalmol. 2012;75:67–70.PubMedGoogle Scholar
  51. 51.
    Otranto D, Brianti E, Gaglio G, et al. Human ocular infection with Dirofilaria repens (Railliet and Henry, 1911) in an area endemic for canine dirofilariasis. Am J Trop Med Hyg. 2011;84:1002–4.PubMedCentralCrossRefPubMedGoogle Scholar
  52. 52.
    Sahdev SI, Sureka SP, Sathe PA. Ocular dirofilariasis: still in the dark in western India? J Postgrad Med. 2012;58:227–8.CrossRefPubMedGoogle Scholar
  53. 53.
    Pauly M, Biswas J, Hussain RN, et al. Periocular dirofilariasis mimicking lacrimal sac mucocoele. Orbit. 2013;32:324–6.CrossRefPubMedGoogle Scholar
  54. 54.
    Nath R, Gogoi R, Bordoloi N, et al. Ocular dirofilariasis. Indian J Pathol Microbiol. 2010;53:157–9.CrossRefPubMedGoogle Scholar
  55. 55.
    Joseph K, Vinayakumar AR, Criton S. Periorbital mass with cellulitis caused by dirofilaria. Indian J Med Microbiol. 2011;29:431–3.CrossRefPubMedGoogle Scholar
  56. 56.
    Bhattacharjee H, Das D, Medhi J. Intravitreal gnathostomiasis and review of literature. Retina (Philadelphia, Pa). 2007;27:67–73.CrossRefGoogle Scholar
  57. 57.
    Biswas J, Gopal L, Sharma T, et al. Intraocular gnathostoma spinigerum. Clinicopathologic study of two cases with review of literature. Retina. 1994;14:438–44.CrossRefPubMedGoogle Scholar
  58. 58.
    Sen K, Ghose N. Ocular gnathostomiasis. Br J Ophthalmol. 1945;29:618–26.PubMedCentralCrossRefGoogle Scholar
  59. 59.
    Kittiponghansa S, Prabriputaloong A, Pariyanonda S, et al. Intracameral gnathostomiasis: a cause of anterior uveitis and secondary glaucoma. Br J Ophthalmol. 1987;71:618–22.PubMedCentralCrossRefPubMedGoogle Scholar
  60. 60.
    Bhende M, Biswas J, Gopal L. Ultrasound biomicroscopy in the diagnosis and management of intraocular gnathostomiasis. Am J Phthalmol. 2005;140:140–2.CrossRefGoogle Scholar
  61. 61.
    De Amorim Garcia Filho CA, Gomes AHB, et al. Clinical features of 121 patients with diffuse unilateral subacute neuroretinitis. Am J Ophthalmol. 2012;153:743–9.CrossRefPubMedGoogle Scholar
  62. 62.
    Oueghlani E, O’Sullivan E, Pavesio CE. Diffuse unilateral subacute neuroretinitis in the United Kingdom. Int Ophthalmol. 2010;30:615–9.CrossRefPubMedGoogle Scholar
  63. 63.
    Barbazetto IA, Lesser RL, Tom D, et al. Diffuse unilateral subacute neuroretinitis masquerading as a white-dot syndrome. Br J Ophthalmol. 2009;93:574–6. 655.CrossRefPubMedGoogle Scholar
  64. 64.
    Anshu A, Chee SP. Diffuse unilateral subacute neuroretinitis. Int Ophthalmol. 2008;28:127–9.CrossRefPubMedGoogle Scholar
  65. 65.
    Gomes AH, Garcia CA, de Segunda P, et al. Optic coherence tomography in a patient with diffuse unilateral subacute neuroretinitis. Arq Bras Oftalmol. 2009;72:185–8.CrossRefPubMedGoogle Scholar
  66. 66.
    Casella AM, Farah ME, de Souza EC, et al. Retinal nerve fiber layer atrophy as relevant feature for diffuse unilateral subacute neuroretinitis (DUSN): case series. Arq Bras Oftalmol. 2010;73:182–5.CrossRefPubMedGoogle Scholar
  67. 67.
    Moraes LR, Cialdini AP, Avila MP, et al. Identifying live nematodes in diffuse unilateral subacute neuroretinitis by using the scanning laser ophthalmoscope. Arch Ophthalmol. 2002;120:135–8.CrossRefPubMedGoogle Scholar
  68. 68.
    Garcia Filho CA, Soares AC, Penha FM, Garcia CA. Spectral domain optical coherence tomography in diffuse unilateral subacute neuroretinitis. J Ophthalmol. 2011;2011:285296.PubMedCentralPubMedGoogle Scholar
  69. 69.
    Cunha LP, Costa-Cunha LV, Souza EC, et al. Intraretinal worm documented by optical coherence tomography in a patient with diffuse unilateral subacute neuroretinitis: case report. Arq Bras Oftalmol. 2010;73:462–3.CrossRefPubMedGoogle Scholar
  70. 70.
    Myint K, Sahay K, Mon S, et al. Worm in the eye: the rationale for treatment of DUSN in South India. Br J Ophthalmol. 2006;90:1125–7.PubMedCentralCrossRefPubMedGoogle Scholar
  71. 71.
    Gass DM, Callanan G, Bowman CB. Oral therapy in diffuse unilateral subacute neuroretinitis. Arch Ophthalmol. 1992;110:675–80.CrossRefPubMedGoogle Scholar
  72. 72.
    Rath S, Honavar SG, Naik M, et al. Orbital cysticercosis: clinical manifestations, diagnosis, management, and outcome. Ophthalmology. 2010;117:600–5.CrossRefPubMedGoogle Scholar
  73. 73.
    Prasad KN, Prasad A, Verma A, et al. Human cysticercosis and Indian scenario: a review. J Biosci. 2008;33:571–82.CrossRefPubMedGoogle Scholar
  74. 74.
    Li JJ, Zhang LW, Li H, et al. Clinical and pathological characteristics of intraocular cysticercosis. Korean J Parasitol. 2013;51:223–9.PubMedCentralCrossRefPubMedGoogle Scholar
  75. 75.
    Wender JD, Rathinam SR, Shaw RE. Intraocular cysticercosis: case series and comprehensive review of the literature. Ocul Immunol Inflamm. 2011;19:240–5.CrossRefPubMedGoogle Scholar
  76. 76.
    Mahendradas P, Biswas J, Khetan V. Fibrinous anterior Uveitis due to Cysticercus cellulosae. Ocul Immunol Inflamm. 2007;15:451–4.CrossRefPubMedGoogle Scholar
  77. 77.
    Ratra D, Phogat C, Singh M, et al. Intravitreal cysticercosis presenting as neovascular glaucoma. Indian J Ophthalmol. 2010;58:70–3.PubMedCentralCrossRefPubMedGoogle Scholar
  78. 78.
    Del Brutto OH, Rajshekhar V, White Jr AC, et al. Proposed diagnostic criteria for neurocysticercosis. Neurology. 2001;24:177–83.CrossRefGoogle Scholar
  79. 79.
    Abba K, Ramaratnam S, Ranganathan LN. Anthelmintics for people with neurocysticercosis. Cochrane Database Syst Rev. 2010;(1):CD000215.Google Scholar
  80. 80.
    Deckers N, Dorny P. Immunodiagnosis of taenia solium taeniosis/cysticercosis. Trends Parasitol. 2010;26:137–44.CrossRefPubMedGoogle Scholar
  81. 81.
    Ogunremi O, Benjamin J. Development and field evaluation of a new serological test for Taenia saginata cysticercosis. Vet Parasitol. 2010;169:93–101.CrossRefPubMedGoogle Scholar
  82. 82.
    Lightowlers MW. Eradication of Taenia solium cysticercosis: a role for vaccination of pigs. Int J Parasitol. 2010;15:1183–92.CrossRefGoogle Scholar
  83. 83.
    Williams DF, Williams GA, Caya JG, et al. Intraocular Echinococcus multilocularis. Arch Ophthalmol. 1987;105:1106–9.CrossRefPubMedGoogle Scholar
  84. 84.
    Ozek MM, Pamir MN, Sav A. Spontaneous rupture of an intraorbital hydatid cyst. A rare cause of acute visual loss. J Clin Neuroophthalmol. 1993;13:135–7.CrossRefPubMedGoogle Scholar
  85. 85.
    Rathinam S, Fritche TR, Srinivasan M, et al. An outbreak of trematode-induced granulomas of the conjunctiva. Ophthalmology. 2001;108:1223–9.CrossRefPubMedGoogle Scholar
  86. 86.
    Rathinam SR, Usha KR, Rao NA. Presumed Trematode-induced Granulomatous Anterior Uveitis: a newly recognized cause of intraocular inflammation in children from South India. Am J Ophthalmol. 2002;133:773–9.CrossRefPubMedGoogle Scholar
  87. 87.
    Rathinam SR, Arya LK, Usha KR, et al. Novel etiological agent: molecular evidence for trematode-induced anterior uveitis in children. Arch Ophthalmol. 2012;130:1481–4.CrossRefPubMedGoogle Scholar
  88. 88.
    Umadevi K, Madhavi R. Observations on the morphology and life-cycle of Procerovum varium (Onji & Nishio, 1916) (Trematoda: Heterophyidae). Syst Parasitol. 2000;46:215–25.CrossRefPubMedGoogle Scholar
  89. 89.
    Hyder AA, Corluka A, Winch PJ. National policy-makers speak out: are researchers giving them what they need? Health Policy Plan. 2011;26:73–82.PubMedCentralCrossRefPubMedGoogle Scholar

Copyright information

© Springer India 2016

Authors and Affiliations

  1. 1.Uveitis ServiceAravind Eye Hospital and PG Institute of OphthalmologyMaduraiIndia
  2. 2.Department of OphthalmologyKasturba Medical CollegeManipal, Udupi DistrictIndia

Personalised recommendations