Table 1. Origin and date of isolation of imipenem-resistant Enterobacter asburiae environmental isolates.

River (city)	Isolate	Date
Arkansas River (Wichita, KS)	E. asburiae AK1	September 1999
Kansas River (Topeka, KS)	E. asburiae K1–K5	September 2000
Des Moines River (Des Moines, IA)	E. asburiae DM1–DM8	August 2001
Mississippi River (Minneapolis, MN)	E. asburiae MS1–MS8	August 2001