External ophthalmomyiasis. Report of four cases

Four cases of external ocular myiasis caused by larvae of Oestrus ovis are reported. Each patient showed some degree of inflammation in the lids and conjunctiva. Regression was only subsequent to removal of parasites from the eye. Two patients had respiratory signs, i.e. rhinitis. For one of these two cases, a short-time admission in the resuscitation unit was recommended following a noticeable bronchospasm. The pathogenetic mechanism of this respiratory distress is not known. Two hypotesis are made.