External ophthalmomyiasis caused by Oestrus ovis in east China

Ophthalmomyiasis Externa and Importance of Risk Factors, Clinical Manifestations, and Diagnosis: Review of the Medical Literature

OBJECTIVE

This review aims to describe and compare the risk factors, clinical course, diagnosis, and parasitologic features of external ophthalmomyiasis. We also discuss the different preventive measures and the effect of global warming in a large case series reported from January 2000 to December 2022.

METHODS

We perform a literature review of reported cases of external ophthalmomyiasis to determine the clinical characteristics, therapeutic management, and information on the organisms that most commonly cause external ophthalmomyiasis.

RESULTS

A total of 312 cases of external ophthalmomyiasis were recorded. The most common causative organism was Oestrus ovis (Linnaeus) (Diptera: Oestridae), accounting for 72.1% of cases, followed by Dermatobia hominis (Linnaeus Jr. in Pallas, 1781) (Diptera: Oestridae) at 5.4%, Lucilia sericata (Meigen) (Diptera: Calliphoridae) at 0.96%, and Chrysomyia bezziana (Villeneuve) (Diptera: Calliphoridae) at 0.96%. Before experiencing symptoms, 43.6% of cases reported having direct contact with flies or being hit in the eye, 33% reported no associated risk factors, 9.3% reported living with sheep and goats, and 7.7% reported a history of foreign objects entering the eye. The most common symptoms for those affected by O. ovis were sudden onset, including a foreign body sensation and movement, redness, tearing, itching, swelling, irritation, photophobia, burning, and ocular secretion. In cases caused by D. hominis, symptoms included eyelid edema, pain, redness, itching, movement within the lesion, ocular irritation, and discharge. Regarding occupational or recreational activity, agriculture, and livestock had the highest incidence, followed by trades and technical activities, being a student, and having traveled to an endemic region for work or recreation.

CONCLUSION

Patients with red eyes may suffer from external ophthalmomyiasis, which requires a thorough examination to diagnose and treat it early. Moreover, as the temperature increases due to climate change, it is essential to consider how this will affect the spread of different pathogens.

The First Genetically Confirmed Case of Human Ophthalmomyasis Due to Oestrus ovis (Diptera Oestridae) in Bosnia and Herzegovina

PURPOSE

Here we present a case of human ophthalmomyasis due to Oestrus ovis in a patient living in an urban area. Dipterians of the Ostridae family may occasionally deposit larvae into the human eye and cause ocular parasitosis called ophthalmomyasis. Cases like this are mostly connected with people who live in close contact with animals, like shepherds, but are rarely presented in urban population.

METHODS

The patient was presented at University Clinic due to problems with his left eye, that persist no matter on treatment in local clinic a few days before. During the slit lamp examination larvae was detected and extracted from the conjunctiva. Genomic DNA was isolated from the sample and genetic analysis was performed.

RESULTS

Larvae was identified as a first-stage larvae of O. ovis.

CONCLUSION

This is the first report of genetically confirmed case of ophthalmomyasis in Bosnia and Herzegovina. In cases like this, clinicians should be aware of possibility of this rarely described presentation of ocular parasitosis since even the urban population can be accidentally affected due to a lack of natural hosts.