Psychodidae (drain fly) infestation in an operating room

The revision openings of the ventilation ducts were opened but no insects could be detected. Because a fly was spotted on a ceiling panel the ceiling was opened and in the ceiling space several drain pipes and electric wiring pipes were visible in close proximity without adequate fitting. [...]the electric outlets were removed and several hundred dead and living drain flies as well as larvae were spotted. [...]none of those complications have been reported with Psychoda grisescens, which are under normal circumstances more of a nuisance in bathrooms and kitchens. Because they primarily live in or near sewage water and were most likely introduced by flood water into the surgery center, carriage of typical fecal bacteria and the risk of contact infection had to be considered in an operating room, making the immediate closure necessary, given the large number of observed insects.