Measles Virus Qualitative PCR

The UW Clinical Virology Laboratory within the Department of Laboratory Medicine and Pathology utilizes a laboratory-developed assay on the Panther Fusion® platform for the rapid detection and differentiation of active wild-type measles infection versus recent vaccination, using real-time PCR.

The assay targets the nucleocapsid (N) gene, enabling detection of both wild-type measles virus and vaccine strain. Differentiation between wild-type and vaccine-associated strains is achieved using strain-specific primers and probes, allowing for selective amplification and detection of each target.

Results are reported qualitatively as Detected or Not Detected. For specimens with detectable viral RNA, a semi-quantitative assessment is provided through reporting of the PCR cycle threshold (Ct) value, which reflects the relative amount of target nucleic acid present in the sample. Lower Ct values correspond to higher viral loads, whereas higher Ct values indicate lower levels of viral RNA.

Ordering requirements:

For UW providers, orders should be placed as part of the "Acute Measles Order Panel" in Epic.

At FHCC orders should only be placed by infection prevention. FHCC clinical teams should order "Acute Measles Rule-Out" to consult FHCC infection prevention regarding measles testing.