2018 Volume 33 Issue 6 Pages 290-295
Arthropods, such as mites and mosquitos, are widely known to transmit pathogens that are responsible for viral hemorrhagic, dengue, and Zika fevers. In addition, several other fly species have the potential to act as vectors for bacterial pathogens in hospitals. An infection control team (ICT) investigated the origin and breeding of small household flies and implemented measures to prevent the outbreak of flies in the operating ward of a Japanese hospital. The ICT placed six light traps in the operating ward and counted and identified trapped flies at monthly intervals from September 2015 to October 2016. Of the 344 flies that were captured in the first month, phorid flies (Phoridae) were the most abundant. Of these, 115 phorid flies were captured in the staff room of the ward. Moth flies (Psychodidae) were the most common around an unused bed washer in one of the rooms in the ward. The ICT considered that phorid flies were attracted by leftover food in the staff room, and moth flies were attracted to damp conditions around the bed washer.
The ICT instructed users of the staff room to clean leftover food, and they washed out the drain pipe of the bed washer before completely removing the bed washer from the operating ward. After implementing these measures, outbreaks of flies in the operating ward have decreased since October 2016. In addition, the ICT isolated and cultured bacteria from fly integuments and from homogenized flies; however, no antibiotic-resistant bacteria were detected. It is necessary to investigate the origin and breeding of small household flies in hospital settings at the earliest and to continue the implementation of fly-control interventions proposed by the ICT.