Volume 98, Issue 4
  • ISSN: 0002-9637
  • E-ISSN: 1476-1645



We report a case of thelaziasis in a 26-year-old female, acquired in Oregon. A total of 14 worms were removed from the patient’s left eye and were morphologically identified as being . Until now, only two species of have been implicated in causing human disease, in Asia and Europe and occasional reports of from the United States of America. Here, we describe a third, previously unreported parasite of humans, (the cattle eyeworm) as an agent of human thelaziasis and the first reported case of human thelaziasis in North America in over two decades.


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  1. Koyama Y, Ohira A, Kono T, Yoneyama Y, Shiwaku K, 2000. Five cases of thelaziasis. Br J Ophthalmol 84: 441.
    [Google Scholar]
  2. Shen J, Gasser RB, Chu D, Wang Z, Yuan X, Cantacessi C, Otranto D, 2006. Human thelaziosis—a neglected parasitic disease of the eye. J Parasitol 92: 872875.
    [Google Scholar]
  3. Naem S, 2011. Thelazia species and conjunctivitis. Pelikan Z, ed. Conjunctivitis—A Complex and Multifaceted Disorder. Rijeka, Croatia: Intech Open Access Press, 201232.
  4. Weinmann CJ, Anderson JR, Roubtzoff P, Connolly G, Longhurst WM, 1974. Eyeworms and face flies in California. Calif Agric 28: 45.
    [Google Scholar]
  5. Doezie AM, Lucius RW, Aldeen W, Hale DV, Smith DR, Mamalis N, 1996. Thelazia californiensis conjunctival infestation. Ophthalmic Surg Lasers 27: 716719.
    [Google Scholar]
  6. Erschow WS, 1928. Drei Thelaziaarten aus der conjunctiva des rindes in der U.S.S.R. [in German]. Dtsch Tierarztl Wochenschr 33: 553556.
    [Google Scholar]
  7. Naem S, 2005. Ultrastructural observations on the surface of Thelazia lacrymalis (Nematoda: Spirurida, Thelaziidae). Acta Vet Hung 53: 205212.
    [Google Scholar]
  8. Naem S, 2007. Morphological differentiation among three Thelazia species (Nematoda: Thelaziidae) by scanning electron microscopy. Parasitol Res 101: 145151.
    [Google Scholar]
  9. Anderson RC, 2000. Nematode Parasites of Vertebrates: Their Development and Transmission, 2nd edition. Wallingford, United Kingdom: CABI Publishing.
  10. Otranto D, Cantacessi C, Testini G, Lia RP, 2006. Phortica variegata as an intermediate host of Thelazia callipaeda under natural conditions: evidence for pathogen transmission by a male arthropod vector. Int J Parasitol 36: 11671173.
    [Google Scholar]
  11. Krafsur ES, Moon RD, 1997. Bionomics of the face fly, Musca autumnalis. Annu Rev Entomol 42: 503523.
    [Google Scholar]
  12. Otranto D, Tarsitano E, Traversa D, De Luca F, Giangaspero A, 2003. Molecular epidemiological survey on the vectors of Thelazia gulosa, Thelazia rhodesi and Thelazia skrjabini (Spirurida: Thelaziidae). Parasitol 127: 365373.
    [Google Scholar]
  13. Otranto D, Traversa D, 2005. Thelazia eyeworm: an original endo-and ecto-parasitic nematode. Trends Parasitol 21: 14.
    [Google Scholar]
  14. Pinto RM, Vicente JJ, Rodrigues HDO, 1998. First report of Thelazia californiensis price (Nematoda, Thelazioidea) in South America from the eyes of a Brazilian deer, mazama gouazoupira (Fischer) (Mammalia, Cervidae). Rev Bras Zool 15: 11211124.
    [Google Scholar]

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  • Received : 08 Nov 2017
  • Accepted : 27 Dec 2017
  • Published online : 12 Feb 2018
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