Comparison of urinary bladder and ear biopsy samples for determining prevalence of Borrelia burgdorferi in rodents in central Europe.

PCR was used to compare urinary bladder and ear biopsy samples from four European species of wild rodents for the presence of Borrelia burgdorferi sensu lato. From 60 paired comparisons of bladder and ear biopsy samples, the PCR results were concordantly positive or negative in 43 samples (71.7%). Of the 17 which differed, 14 bladder samples were positive and ear samples were negative while the converse occurred for three samples. Thus ear biopsy samples led to a significantly lower estimate of infection than bladder biopsy samples. This suggests that the use of ear biopsy samples in epidemiological studies of B. burgdorferi in Central European rodents is likely to lead to underestimates of the prevalence.