Detection of measles, mumps, and rubella viruses.

Measles, mumps, and rubella are infections caused by RNA viruses of the same name and are vaccine preventable. The vaccines are frequently administered in a trivalent form. Laboratory diagnostic methods can include indirect detection via antibody (IgM and IgG) detection methods and direct detection by viral culture or viral genome detection. There are challenges for the laboratory in areas with low prevalence due to high vaccine uptake. In those areas, routine serological methods such as IgM detection may have a reduced positive predictive value and thus require confirmation by other methods. Direct detection of viral genomic material using reverse transcription polymerase chain reaction (RT-PCR) methodologies can play an important role for laboratory confirmation of acute infections. Furthermore, genotyping of these three viruses provides useful molecular epidemiological data for differentiating vaccine from wild-type strains, linking cases and outbreaks, and tracking geographic spread and elimination. The purpose of this chapter is to provide guidance for the laboratory diagnosis of measles, mumps, and rubella virus infections. Where assays are commercially available or previously published, the appropriate references are provided as well as brief comments on the interpretation of results. Detailed protocols are provided for the molecular assays which have been developed and more commonly applied in recent years.