Polyomaviruses (PyV) are small viruses with a circular genome. BKPyV and JCPyV are types of polyomaviruses ubiquitous in the human population, and their prevalences increase with age. In healthy individuals, they are not associated with any primary disease but cause persistent infection and can sometimes reactivate.

Reactivation of BKPyV, and less often JCPyV, may occur during immunosuppression during renal transplantation. This may lead to clinically silent nephropathy followed by progressive renal failure, which may be confused with transplant rejection. BKPyV hemorrhagic cystitis is a common outcome of hematopoietic stem cell transplantation. Progressive multifocal leukoencephalopathy (PML) is a rare demyelinating brain infection caused by JCPyV in immunosuppressed patients.

Since there are no standard treatments for these viruses, reducing immunosuppression or restoring immunocompetence are the cornerstones of treatment. To facilitate pre-emptive treatment, quantitative PCR (qPCR) is typically used to monitor PyV load in the urine, blood, or, in suspected PML, cerebrospinal fluid (CSF) samples. The accuracy of qPCR is dependent on the use of assay standards. Therefore, the result includes two-fold variation: 1) that of the sample and 2) that of the standards the sample is compared to.

QIAquity digital PCR (dPCR) is an interesting alternative to qPCR because it’s a standard-free method and is less likely to be affected by possible inhibitory factors. In this webinar, we'll discuss the results of detecting and quantifying JCPyV and BKPyV using QIAquity dPCR in clinical research samples using laboratory designed primers and probes.