# “Fly in the eye: Oestrus ovis” – a case report and a review from India

## TL;DR

A case of eye infection caused by sheep nasal botfly larvae is reported from India, highlighting the need for careful diagnosis.

## Contribution

This paper presents a recent case of Oestrus ovis-induced ophthalmomyiasis from North India and reviews related literature.

## Key findings

- A farmer was diagnosed with Oestrus ovis larvae in his conjunctival sac after being misdiagnosed with acute conjunctivitis.
- Microbiological analysis confirmed the presence of Oestrus ovis larvae in the patient's eye.
- The study emphasizes the importance of thorough examination in cases resembling acute conjunctivitis.

## Abstract

Ophthalmomyiasis externa is the most common manifestation of Oestrus ovis (sheep nasal botfly) in humans. Several cases have been reported from various regions of India with the first case reported by Elliot in 1910. Here, we report such a case from North India along with the review of literature from India of the last fifteen years. A farmer presented to us with unilateral ocular symptoms of redness, foreign body sensation and severe watering in left eye who was misdiagnosed as acute conjunctivitis elsewhere. On slit lamp examination, multiple translucent larvae were found in his conjunctival sac. Microbiological analysis revealed them to be larvae of the Oestrus ovis fly. External ophthalmomyiasis is an uncommon entity with ocular symptoms mimicking acute conjunctivitis, hence a thorough examination in every suspicious case of acute red eye is important.