Isolation of Salmonella spp. from the housefly, Musca domestica L., and the dump fly, Hydrotaea aenescens (Wiedemann) (Diptera : Muscidae), at caged-layer houses

Flies, especially houseflies, are widely recognized as potential reservoirs and vectors of foodborne Salmonella pathogens. In this study, flies were c ollected at caged-layer facilities that had produced eggs that were implica ted as the food vehicle in two recent outbreaks of Salmonella Enteritidis i nfections. The flies were separated by species into pools for microbiologic al testing. A total of 15 species pools of houseflies, Musca domestica L., and 7 species pools of bronze dump flies, Hydrotaea aenescens (Wiedemann) ( Diptera: Muscidae), were analyzed. Salmonella Enteritidis was isolated from 2 of the 15 pools of houseflies. Other species of Salmonella were isolated from three pools of flies, including Salmonella Infantis from houseflies a nd from dump flies and Salmonella Heidelberg from houseflies. Salmonella Mb andaka was isolated from a lesser mealworm, Alphitobius diaperinus (Panzer) (Coleoptera: Tenebrionidae).