in case of leptospirosis the sample include blood,urine,cerebrospinal fluid and uterine fluids,also the sample including aborted fetus Biopsy of kidney,liver,spleen,eye,lung and brains(from dead animals)
The source of the sample (serum, urine, aqueous humor, CSF) really depends on the stage of infection. In the early phase of the disease (until day 10, more or less), the leptospires are in the hematogenous phase, thus they can be found mainly in the blood. After that, bacteria are cleared from blood and migrate to other organs. So the best source would be organs extracts (kidney, liver), urine...
I agree with the suggested sumary mentioned above and I want to add that the best sourse of the sample is also depending of the clinical variant of the desease,not only on the desease & infection stage!!!
According to my experience the most importantre samples are sera,whole blood,and urine. Not only for strain culture purposes but also for PCR purposes!!!
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