CDC and public health officials in several states investigated 13 multistate outbreaks of Salmonella infections with serotypes Agona, Alachua, Altona, Anatum, Braenderup, Enteritidis, Infantis, Manhattan, Montevideo, Muenchen, Newport, and Oranienburg. Epidemiologic, laboratory, and traceback evidence indicated that contact with backyard poultry, such as chicks and ducklings, from multiple hatcheries was the likely source of these outbreaks.