The Challenges and Strategies for Laboratory Diagnosis of Measles in an International Setting

Abstract

Serum-based measles-specific IgM EIAs are the recommended laboratory assays for diagnosis of acute measles infections and appear to be sufficient for measles control programs. However, serum samples are not ideal for molecular characterization of measles virus. Although neither laboratory nor field-based diagnostic tests that rival the EIAs have been developed, laboratory surveillance could be improved if specimen collection were simplified. Ideally the collection method should be noninvasive, have no requirement for a cold chain, and/or have no requirement for technically sophisticated equipment. Two alternative specimen collection technologies appear promising and can be used for both diagnostics and for collecting pertinent genotyping information: oral fluid and filter paper collection methods. These methods are compared along with their respective utilities in supporting measles diagnosis and strain surveillance.

Genotyping of Measles Virus in Clinical Specimens on the Basis of Oligonucleotide Microarray Hybridization Patterns

“…Genotyping of MV isolates is an important component of measles surveillance because it provides a means to track the transmission pathways of the virus (2,3,23,25). Genetic characterization of viral isolates is the only means to distinguish between a vaccine reaction and disease caused by wild-type virus.…”

“…To this end, WHO has developed a global network of measles laboratories. These laboratories perform serologic assays to detect MV-specific immunoglobulin M antibodies and conduct genetic characterization of wild-type MVs isolated from outbreaks and sporadic cases (2,33). Molecular epidemiological studies, along with standard case investigation and reporting, provide the necessary tools to monitor MV circulation and gauge the success of vaccination programs (23).…”

Measles Virus IgG Avidity Assay for Use in Classification of Measles Vaccine Failure in Measles Elimination Settings

“…Many laboratories are uneasy about reporting IgM-positive results from single serum specimens obtained from sporadic cases of rash illnesses, particularly in elimination settings, where tests are rarely used. Additionally, regarding quality of detection, declining levels of IgM antibodies in samples collected more than 4 weeks after rash onset may lead to false-negative results (4). In this context, detection of low-avidity IgG antibodies could be used to rule in these measles cases and provide assurance that a costly investigation is not initiated based on a false IgM-positive result (36,38).…”

Calibration and Evaluation of Quantitative Antibody Titers for Measles Virus by Using the BioPlex 2200

“…The BioPlex 2200 MMRV IgG assay captures IgG antibodies directed at all measles antigens, including those that may not contribute to immunity, such as antibodies directed against nucleoprotein. PRNT measures with greater sensitivity neutralizing antibodies, directed at specific epitopes of the surface hemagglutinin and fusion proteins (24,30,32). These differences make direct comparison of the two assays problematic, especially at low antibody titers (14,15,26).…”