Particle.news
Download on the App Store

Greek Case Shows Sheep Bot Fly Pupated Inside Human Sinuses

The peer-reviewed case challenges long-held assumptions about where the sheep bot fly can mature.

Overview

  • After flies swarmed her face near grazing sheep in September 2025, a 58-year-old outdoor worker in Greece developed sinus pain and in October 2025 she sneezed out a larva that led her to seek care.
  • An ear, nose, and throat surgeon removed 10 larvae and one puparium from her maxillary sinuses, with the puparium being the hard case a larva forms as it turns into an adult fly.
  • Visual inspection and DNA testing identified the organisms as Oestrus ovis, the sheep bot fly that normally lives in the nasal passages of sheep and goats rather than people.
  • The report documents pupation inside a human host, a stage long considered biologically implausible in mammals because sinus temperature, humidity, and immune defenses usually block it.
  • The authors point to a severely deviated nasal septum and a heavy larval load as likely enablers of late-stage development, and they urge vigilance and more cases before any claim of adaptation to humans.