Accurate description of Salmonella prevalence is an important step toward understanding the epidemiology of the organism. A U.S. national prevalence estimate of fecal prevalence of Salmonella species showed that the organisms were commonly detected on farms. with 58 of 160 farms (38.2%) with one or more positive sample. The same survey, however, suggested that the prevalence rate differed by geographic region, with the southeastern area of the country having more than double the prevalence of the Midwest.