Septicemic salmonellosis caused by Salmonella Hessarek in wintering and migrating Song Thrushes (Turdus philomelos) in Spain.

We investigated two mortality events in wintering and migrating Song Thrushes (Turdus philomelos) in Catalonia, northeastern Spain in 2009 and 2010. Both episodes occurred in late February to mid-March during the spring migration. Salmonellosis produced by the serotype Salmonella enterica subsp. enterica serotype Hessarek (S. Hessarek) was identified as the cause of death in both episodes. Poor body condition, marked splenomegaly, and microscopic disseminated intravascular coagulation with numerous intravascular and tissular bacteria were the most consistent findings. Macro-restriction profiling by pulsed-field gel electrophoresis (PFGE) using XbaI was performed for epidemiologic typing of the S. Hessarek isolates. Two clusters were discernible, that are possibly related, with a similarity of 82.8%. Analysis comparing pectoral muscle and subcutaneous fat scores from the Song Thrushes that died from S. Hessarek with those from healthy Song Thrushes from nearby areas during 2009 and 2010 suggest that poor body condition was associated with the S. Hessarek infection.