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Year : 2014  |  Volume : 32  |  Issue : 1  |  Page : 84--86

Ocular thelaziasis in a 7-month-old infant

AK Handique1, A Tamuli2, AM Khan3,  
1 Department of Ophthalmology, Assam Medical College and Hospital, Dibrugarh 786002 Assam, India
2 Department of Ophthalmology, Lion KK Saharia Hospital, AT Road, Dibrugarh 786001 Assam, India
3 Division of Entomology and Filariasis, Regional Medical Research Centre, Dibrugarh, Assam, India

Correspondence Address:
A M Khan
Division of Entomology and Filariasis, Regional Medical Research Centre, Dibrugarh, Assam


Human thelaziasis is a zoonotic eye disease caused by a nematode parasite called Thelazia. In India, seven human cases of Thelazia have been reported earlier. This is the first case report of an infant infected with Thelazia. During the month of July, 2012, the infant was presented with an eye problem to the eye clinic from a village of Dibrugarh. Five worms (three female and two male) were recovered from the left eye of the infant. Thelazia infection is rare in infant, and report of this case is suggestive of prevalence of infection in the area and warrants further investigation.

How to cite this article:
Handique A K, Tamuli A, Khan A M. Ocular thelaziasis in a 7-month-old infant.Indian J Med Microbiol 2014;32:84-86

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Handique A K, Tamuli A, Khan A M. Ocular thelaziasis in a 7-month-old infant. Indian J Med Microbiol [serial online] 2014 [cited 2020 Nov 30 ];32:84-86
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Thelaziasis commonly known as eyeworm or oriental eye worm disease is a zoonotic infection of eye mainly reported in dogs, cats, cattle and wild mammals. Thelaziasis is not frequently found in humans; however, tropical humid climate of hilly regions favours vector propagation and human infection. Countries such as China, Korea, Japan, Italy, Russia and India reported most of the human infection. [1] Clinical manifestation includes conjunctivitis, ocular pruritus, lacrimation, congestion and discharge, corneal oedema and corneal ulceration in severe infection. [2],[3] The role of vector (fly) involved in the transmission of thelaziasis has been a matter of discussion, however, investigation has proved that Musca domestica Linnaeus (Diptera: Muscidae) is not a vector of Thelazia callipaeda in Europe. [4] Studies on vectors confirmed that Phortica okadai and Phortica variegata is the vector of T. callipaeda in China and southern Europe. [5] In India, the role of vector in the transmission of thelaziasis has not been studied so far. The increase in number of human cases in India merits for study of transmission dynamics of thelaziasis.

 Case Report

Parent of a 7-month-old infant of a village located at Moranhat (27°10'25.52"N 94°55'01.33"E) of the district Dibrugarh Assam had reported to the eye clinic with an eye problem of their infant in the month of July 2012. Parents of the infant are of low socio-economic status and depend upon agriculture for their livelihood. The family keeps the dog as pet animal. On clinical examination, left eye showed watery secretion and revealed presence of creamy thread like worms. The infant was kept under general anaesthesia. After surgical asepsis, eye-lids were opened with a speculum and living worms were located and removed by plane forceps under a surgical microscope. Conjunctival sac was irrigated with normal saline solution and thoroughly searched for worms. A total of five worms were recovered and preserved in 70 % alcohol. Worms were taken to the research laboratory for identification. We put the subject on treatment for 5 days using tobramycin eye drop along with the lubricating eye-drop carboxy methyl cellulose. Patient got cured of illness the next day without any noticeable symptom. Follow-up of the patient for 6 months revealed no recurrence of symptoms of the disease. Infant became fully cured and healthy. Worms were observed under light microscope with × 10 and × 40 magnifications and photographed, especially, anterior, posterior and middle portion of the worm [Figure 1]. Male worm is short in length having coiled tail with spicules (long string like structure) and caudal papillae while, female worms are longer in length with uncoiled tail and non-embryonated eggs [Figure 1]b and d-g]. Male worm measured 11-12 mm in length and 0.37-0.38 mm in breadth. Female worms were 18-21 mm in length and 0.45-0.47 mm in breadth. Buccal capsule in male worms was distinct. In female worm, vaginal opening was located in the anterior part of the body of the worms just above the junction point of oesophagus and intestine [Figure 1]c. Anal opening in the female worm was distinct and located at the posterior part of the worm [Figure 1]d. Transverse cuticular striations were present throughout the body of the worm of both sexes [Figure 1]h and i. We could not count the number of cuticular striation and pairs of papillae on the body of the worm due to limited facility.{Figure 1}


Two species of Thelazia namely T. callipaeda and Thelazia californiensis are responsible for human infection. T. callipaeda is distributed mainly in Asian countries such as China, Japan, Korea, India and Russia while T. californiensis is mainly confined to the United States. [6],[7] We did microscopic observation of worms for morphological characters like presence of cuticular striations on the body, position of the VO in the anterior part of the female worms above to the oesophagus and intestine junction point, presence of caudal papillae in pairs (though exact numbers could not be ascertained) and presence of prominent spicules in the male worms. Comparison of morphological characters of worms with published literature strongly suggests that the worm is T. callipaeda. [8] Studies done on thelaziasis in Italy, China and Korea have shown the medical and zoonotic importance of this parasite and detailed prevalence and transmission study further ascertained its importance with regards to human and animal health. [9],[10] The infant's family keeps a dog as a pet that lives In close contact of the family members. Hence, there is a possibility of transmission of Thelazia infection from dog to the infant. Though India reports seven human cases of thelaziasis, [11],[12] no study pertaining to the transmission dynamics of T. callipaeda is available. North-eastern part of India possess tropical climate with hilly terrain and longer monsoon period, which is conducive for vector borne diseases. The presence of this zoonotic infection in northeastern region suggests its importance concerning human and animal health. Further, of the seven human cases reported from India, four are from north-eastern region. Therefore, a detailed epidemiological study on this parasite is needed to shed some more light on the present status of this infection in the northeastern part of India.


The authors acknowledge the support and help of the parent of the subject who has taken pains during the investigation and follow-up of the case.


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