Electrocuting insect traps (EIT) are popular devices frequently used by hom
eowners and food handlers attempting to localize the control of flying inse
cts, including the ubiquitous house fly (Musca domestica L.). The traps con
tain a visual attractant and a high-voltage metal grid. Upon contact with t
he grids, the insects are disintegrated by the high voltage. As part of a s
ystematic evaluation of EITs and their role in infectious disease spread, w
e quantitated spread of bacteria and a bacterial virus during electrocution
or house flies. We loaded flies with Serratia marcescens or with the Esche
richia coli phage Phi X174 and placed sprayed or fed flies into a room cont
aining an EIT. While flies were being electrocuted, liberated particles and
bacteria were assayed via agar plates or via air filtration samplers. Spra
yed flies released one of every 10,000 of the added bacteria or viruses, an
d fed flies released one of every 1,000,000 of the consumed bacteria or vir
uses. Results of our studies suggest EITs could play a role in the spread o
f infectious disease agents, but the potential is influenced by the insect'
s route of contamination.