Isolation of Rickettsia akari from a patient in a region where Mediterranean spotted fever is endemic.

Rickettsia akari was isolated from blood collected from a patient in Croatia in 1991. We believe this is the first human isolate of R. akari to be reported in more than 40 years and the first ever from southern Europe. The Croatian isolate was antigenically and genetically indistinguishable from the prototype American strain and a Ukrainian strain. In all probability, rickettsialpox would be diagnosed more frequently and over a wider geographic area if physicians gave greater consideration to the diagnosis and if laboratory diagnostic methods were better able to distinguish among spotted fever group rickettsioses.