Flies were collected at caged-layer poultry houses that had produced eggs that were implicated as the food vehicle in recent outbreaks of Salmonella Enteritidis infections. The flies were grouped into pools that were tested for Salmonella spp. A total of 15 pools of house flies, Musca domestica L. and 7 pools of dump flies, Hydrotaea aenescens (Wiedemann) (Diptera: Muscidae) were tested. Salmonella Enteritidis was isolated from 2 of the 15 pools of house flies. Other isolates included: Salmonella Infantis from one pool of house flies and one pool of dump flies, and Salmonella Heidelberg from one pool of houseflies. These results are a strong indication that house flies and other disease-carrying flies should be considered a potential risk factor in the prevention of outbreaks of Salmonella Enteritidis involving eggs.