This scanning electron micrograph (SEM) depicts a number of rod-shaped, motile, Gram-negative Salmonella infantis bacteria, Magnification 2255x. Clinical features of Salmonellosis include fever, abdominal cramps, and diarrhea, which is sometimes bloody. Occasionally these bacteria can establish a localized infection such as septic arthritis, or can even progress to sepsis, which occurs due to the systemic spread of these pathogens. The etiologic agents are members of the Gram-negative family of bacteria Enterobacteriaceae, of which approximately 2000 serotypes cause human disease, including Salmonella infantis. The incidence of salmonellosis is estimated at 1.4 million cases occurring annually in the United States, and of these, approximately 30,000 are culture-confirmed cases reported to CDC. See image n0829505 on the site.