Nasal myiasis by Oestrus ovis second stage larva in an immunocompetent man: case report and literature review

Objective: We report a case of an Oestrus ovis larva which developed into the second larval stage within a healthy, immunocompetent human, and we review the relevant literature. Methods: Clinical case report and Pubmed search of reports of human nasal myiasis due to Oestrus ovis, especially those describing the larval stage. Results: Humans are not normally hosts of the sheep nasal bot fly, but infestations by its larvae have been described. The eye is the most common site, but larvae have occasionally been found in the human nose. Transformation of larvae into the second and third stages, within the human nose, is even more uncommon. Conclusion: To the best of our knowledge, we report the first Swedish case, and the third case world-wide, of Oestrus ovis larval development beyond the first larval stage, within an immunocompetent, healthy human.