Diagnostic accuracy of commercially available serological tests for the detection of measles and rubella viruses: a systematic review and meta-analysis.

Measles and rubella serological diagnoses are done by IgM detection. The World Health Organization Global Measles and Rubella Laboratory Network previously endorsed Siemens Enzygnost enzyme-linked immunosorbant assay kits, which have been discontinued. A recommended replacement has not been determined. We aimed to search for suitable replacements by conducting a systematic review and meta-analysis of IgM detection methods that are currently available for measles and rubella. A systematic literature search was performed in Medline, Embase, Global Health, Cochrane Central, and Scopus on March 22 and on 27 September 2023. Studies reporting measles and/or rubella IgM detection with terms around diagnostic accuracy were included. Risk of bias was assessed using QUADAS tools. Meta-DiSc and R were used for statistical analysis. Clinical samples totalling 5,579 from 28 index tests were included in the measles meta-analysis. Sensitivity and specificity of the individual measles studies ranged from 0.50 to 1.00 and 0.53 to 1.00, respectively. Pooled sensitivity and specificity of all measles IgM detection methods were 0.94 (CI: 0.90-0.97) and 0.94 (CI: 0.91-0.97), respectively. Clinical samples totalling 4,983 from 15 index tests were included in the rubella meta-analysis. Sensitivity and specificity of the individual rubella studies ranged from 0.78 to 1.00 and 0.52 to 1.00, respectively. Pooled sensitivity and specificity of all rubella IgM detection methods were 0.97 (CI: 0.93-0.98) and 0.96 (CI: 0.93-0.98), respectively. Although more studies would be ideal, our results may provide valuable information when selecting IgM detection methods for measles and/or rubella.

Dimeric immunoglobulin A as a novel diagnostic marker of measles infection.

IMPORTANCE: The world is facing a measles resurgence, and improved diagnostic tests for measles infection are an urgent World Health Organization research priority. Detection of measles-specific immunoglobulin M (IgM) as a standard diagnostic test has low positive predictive value in elimination settings, and there is a need for new biomarkers of measles infection to enable enhanced surveillance and response to outbreaks. We demonstrate the detection of measles-specific dimeric immunoglobulin A (dIgA) in patients with confirmed measles infections using a new indirect enzyme-linked immunosorbent assay protocol that selects for the dIgA fraction from total IgA in the blood. The magnitude of measles-specific dIgA responses showed a low correlation with IgM responses, and our results highlight the potential of dIgA for further development as an alternative and/or complementary biomarker to IgM for serological diagnosis of measles infection.

Genome sequence of a measles virus strain with a novel loss of stop codon mutation in the phosphoprotein gene.

Measles virus genotype B3 coding-complete genome sequence from a 2019 case showed a novel mutation in the phosphoprotein (P) gene that abrogates the established stop codon. A downstream stop codon has been identified, resulting in a putative P that would be 19 amino acids longer than wild type.

Mumps resurgence in a highly vaccinated population: Insights gained from surveillance in Canada, 2002-2020.

Although mumps vaccination has been routine in Canada for decades, mumps cases and outbreaks continue to occur periodically. Mumps surveillance, including monitoring of the mumps virus genotype associated with disease activity, is important to document baseline activity and to advance further research into vaccine effectiveness. Here we describe a detailed analysis of mumps cases that have been detected in Canada from 2002 to 2020, with a focus on the mumps molecular epidemiology. In total, 7395 cases of mumps were reported to the surveillance system, with outbreaks occurring in the years 2007, 2010 and 2016 to 2018. Adolescents and young adults aged 15 to 29 years had the highest risk of being a case (rate ratios ranging from 1.50 to 2.29), compared to adults aged 30 to 39. Genotypes of mumps viruses were determined in 3225 specimens. Genotype G was predominantly detected (96% of genotyped specimens) and was first reported in 2005. Other genotypes were more likely to be detected in cases that also reported travel (or were linked to imported cases) than the cases with genotype G detected (p < 0.0001). The genotype G viruses had little sequence diversity in the 316 nucleotide window used for genotyping (the small hydrophobic protein gene) and mainly belonged to a single phylogenetic lineage that included the MuVi/Sheffield.GBR/1.05 reference sequence. The analysis of over ten years of data has demonstrated that mumps genotype G, specifically belonging to a single lineage, the Sheffield lineage, is the endemically circulating virus in Canada. This lineage is seen also in other countries using the genotype A vaccine. Mumps remains endemic despite high MMR vaccination coverage which has been sufficient to eliminate circulation of measles and rubella in Canada, raising the hypothesis of the evolution towards a vaccine escape mumps virus.

Development of a rapid, internally controlled, two target, real-time RT-PCR for detection of rubella virus.

Rubella surveillance in elimination setting relies on rapid molecular detection of the virus. In this study a multiplex real-time RT-PCR assay for the detection of rubella virus was validated. The assay includes three independent probes with unique reporter dyes for the simultaneous detection of the rubella viral coding regions for envelope glycoprotein E1 and non-structural p150 protein, and an endogenous control (human RNaseP). Using dilution series of synthetic RNAs, the limits of detection were determined to be at least 50 copies of rubella RNA. The assay is reproducible with low intra-assay and inter-assay coefficients of variation for both the E1 and the p150 targets. After testing 62 confirmed rubella positive and 165 rubella negative archival clinical samples, the sensitivity and specificity of the multiplex assay were 98.4 and 100 %, respectively. No cross reactivity was identified with clinical specimens positive for eleven other viruses. This multiplex assay successfully detected nine viral genotypes including the predominant genotypes 1E, 1G, 1J, and 2B as well as the 1a vaccine genotype.

Development of a rapid, internally controlled, two target, real-time RT-PCR for detection of measles virus.

Vaccination has greatly reduced global measles incidence, however measles remains endemic in many regions worldwide. Measles surveillance relies on high performance molecular detection of the virus. We have developed and validated a multiplex rRT-PCR assay for the detection of measles virus. The assay includes three independent probes with unique reporter dyes for the simultaneous detection of the measles hemagglutinin gene, nucleoprotein gene and endogenous RNaseP control. Using dilution series of synthetic RNAs the limits of detection were determined to be approximately 20 copies of measles RNA. The assay is extremely reproducible with very low intra-assay and inter-assay coefficients of varation for both the N and the H targets. After testing 68 confirmed measles positive and 86 measles negative archival clinical samples our data shows the multiplex assay has a sensitivity and specificity of 100 %, and a 100 % concordance with the expected results. No cross reactivity was identified with clinical specimens positive for six other viruses. According to the WHO, currently only the B3, D4, D8, H1 measles genotypes of the 24 recognized genotypes continue to circulate and this new multiplex assay successfully detected all four of those genotypes as well as six other genotypes.

Evaluation of Diagnostic Accuracy of Eight Commercial Assays for the Detection of Rubella Virus-Specific IgM Antibodies.

Rubella and congenital rubella syndrome are caused by the rubella virus and are preventable through vaccination, making disease eradication possible. Monitoring of progress toward global eradication and local elimination requires high-quality, sensitive disease surveillance that includes laboratory confirmation of cases. Previous evaluations of anti-rubella IgM detection methods resulted in the broad adoption of the Enzygnost (most recently manufactured by Siemens) enzyme-linked immunosorbent assay (ELISA) kits within WHO's global measles and rubella laboratory network, but they have been discontinued. This study evaluated seven comparable ELISAs from six manufacturers (Trinity Biotech, Euroimmun, Clin-Tech, NovaTec and Virion\Serion) as well as one automated chemiluminescent assay (CLIA) from DiaSorin. These assays include three IgM capture assays and five indirect ELISAs. A panel of 238 sera was used for the evaluation that included 38 archival rubella IgM-positive sera and 200 sera collected from patients with symptomatically similar diseases, such as measles, dengue, parvovirus B19 infection, and roseola. With this panel of sera, the sensitivity of the methods ranged from 63.2% to 100% and the specificity from 80.0% to 99.5%. No single method had both sensitivity and specificity of >90%, unless sera with equivocal results were considered presumptively positive. Some assays, particularly the Serion ELISA, had a large number of false positives with parvovirus B19 IgM-positive sera as well as sera from confirmed measles cases. The performance characteristics identified in this evaluation serve as a reminder to not rely solely on rubella IgM results for case confirmation in elimination settings.

Evaluation of Diagnostic Accuracy of Eight Commercial Assays for the Detection of Measles Virus-Specific IgM Antibodies.

The World Health Organization (WHO) has targeted measles for global eradication through mass immunization. For effective monitoring of eradication targets, high-quality surveillance is needed. The detection of IgM antibodies, specific to the measles virus, with the use of commercial enzyme-linked immunosorbent assays (ELISA or EIA) is broadly used within the WHO global measles and rubella laboratory network for laboratory confirmation, and in particular, ELISA kits manufactured by Siemens (Enzygnost kits) have been primarily used. Spurred by the discontinuation of these kits, this study aims to report on the clinical sensitivity and specificity of comparable commercial ELISA kits and one automated chemiluminescent immunoassay (CLIA) method. A panel of 239 serum samples was assembled that included sera from confirmed measles cases (n = 50) and probable post-MMR vaccine response (n = 2). Measles-negative sera (n = 187) were collected from individuals presenting with other fever and rash illnesses. A total of 7 ELISA kits (Euroimmun native antigens and recombinant nucleoprotein, IBL, Clin-Tech Microimmune, NovaTec NovaLisa, Serion, and Siemens Enzygnost) and one CLIA method (DiaSorin LIAISON XL) were evaluated. The ELISA kits included two IgM capture methods and five indirect methods. Calculated sensitivities and specificities ranged from 75.0% to 98.1% and 86.6% to 99.5%, respectively. The parvovirus B19 IgM positive sera were noted to cause false-positive results, particularly for the ELISA kits from Serion and NovaLisa; specificities for this subset of samples ranged from 51.4% to 100.0%. The capture IgM ELISA methods provided the best combination of sensitivity and specificity.

Self-Collected Specimens Revealed a Higher Vaccine- and Non-Vaccine-Type Human Papillomavirus Prevalences in a Cross-Sectional Study in Akuse.

BACKGROUND: Population-specific epidemiologic data on human Papillomavirus infection, which are limited in most of the SubSaharan African countries, are necessary for effective cervical cancer prevention. This study aimed to generate population-specific data on human Papillomavirus infections, and determine which of these, self-collected and provider-collected specimens, gives a higher estimate of the prevalence of human Papillomaviruses, including vaccine and non-vaccine-type human Papillomavirus. METHODS: In this cross-sectional study, following a questionnaire-based collection of epidemiological data, self-, and provider-collected specimens, obtained from women 15-65 years of age, were analysed for human Papillomavirus types by a nested-multiplex polymerase chain reaction, and for cervical lesions by Pap testing. HPV data were categorised according to risk type and vaccine types for further analysis. RESULTS: The difference between the overall human Papillomavirus infection prevalences obtained with the self-collected specimens, 43.1% (95% CI of 38.0-51.0%) and that with the provider-collected samples, 23.3% (95% CI of 19.0-31.0%) were significant (p ≤ 0.001). The prevalence of quadrivalent vaccine-type human Papillomaviruses was 12.3% with self-collected specimens, but 6.0% with provider-collected specimens. For the nonavalent vaccine-types, the prevalences were 26.6% and 16.7% respectively. There were multiple infections involving both vaccine-preventable and nonvaccine preventable high-risk human Papillomavirus genotypes. CONCLUSION: The Akuse subdistrict can, therefore, be said to have a high burden of human Papillomavirus infections, which included nonvaccine types, as detected with both self-collected and provider-collected specimens. These imply that self-collection is to be given a higher consideration as a means for a population-based high-risk human Papillomavirus infections burdens assessment/screening. Additionally, even with a successful implementation of the HPV vaccination, if introduced in Ghana, there is still the need to continue with the screening of women.

MicroRNA and mRNA Dysregulation in Astrocytes Infected with Zika Virus.

The Zika virus (ZIKV) epidemic is an ongoing public health concern. ZIKV is a flavivirus reported to be associated with microcephaly, and recent work in animal models demonstrates the ability of the virus to cross the placenta and affect fetal brain development. Recent findings suggest that the virus preferentially infects neural stem cells and thereby deregulates gene expression, cell cycle progression, and increases cell death. However, neuronal stem cells are not the only brain cells that are susceptible to ZIKV and infection of other brain cells may contribute to disease progression. Herein, we characterized ZIKV replication in astrocytes, and profiled temporal changes in host microRNAs (miRNAs) and transcriptomes during infection. We observed the deregulation of numerous processes known to be involved in flavivirus infection, including genes involved in the unfolded protein response pathway. Moreover, a number of miRNAs were upregulated, including miR-30e-3p, miR-30e-5p, and, miR-17-5p, which have been associated with other flavivirus infections. This study highlights potential miRNAs that may be of importance in ZIKV pathogenesis.

Human papillomavirus genotypes in invasive cervical squamous cell carcinoma in Trinidad.

OBJECTIVE: To determine the relative contribution of known high-risk human papillomavirus (HPV) genotypes to the occurrence of cervical cancers in Trinidad. METHODS: The distribution of HPV genotypes in cases of invasive cervical squamous cell carcinoma in Trinidad was investigated. This study was a follow-up to an investigation of HPV genotypes in 310 nonsymptomatic women in Trinidad. The latter study showed that cervical HPV prevalence and heterogeneity of genotypes were high in the study population; notably, the genotypes targeted by the available HPV prophylactic vaccines were not the most common types. RESULTS: The current study of 85 cases of invasive cervical squamous cell carcinomas demonstrated that the previously observed heterogeneity in HPV genotype distribution is lost in cases of invasive cervical cancer, with the vaccine-targeted HPV types HPV 16 and HPV 18 becoming the most prevalent. CONCLUSIONS: HPV 16 and HPV 18 were the primary HPV genotypes associated with cases of invasive squamous cell carcinoma in the current Trinidad study. This strong association leads us to conclude that the HPV vaccines targeting HPV 16 and HPV 18 may contribute to reducing the cervical cancer burden in Trinidad.

Human papillomavirus genotypes in invasive cervical squamous cell carcinoma in Trinidad / Genotipos de virus de los papilomas humanos en carcinoma cervicouterino escamocelular invasor en Trinidad

OBJECTIVE: To determine the relative contribution of known high-risk human papillomavirus (HPV) genotypes to the occurrence of cervical cancers in Trinidad. METHODS: The distribution of HPV genotypes in cases of invasive cervical squamous cell carcinoma in Trinidad was investigated. This study was a follow-up to an investigation of HPV genotypes in 310 nonsymptomatic women in Trinidad. The latter study showed that cervical HPV prevalence and heterogeneity of genotypes were high in the study population; notably, the genotypes targeted by the available HPV prophylactic vaccines were not the most common types. RESULTS: The current study of 85 cases of invasive cervical squamous cell carcinomas demonstrated that the previously observed heterogeneity in HPV genotype distribution is lost in cases of invasive cervical cancer, with the vaccine-targeted HPV types HPV 16 and HPV 18 becoming the most prevalent. CONCLUSIONS: HPV 16 and HPV 18 were the primary HPV genotypes associated with cases of invasive squamous cell carcinoma in the current Trinidad study. This strong association leads us to conclude that the HPV vaccines targeting HPV 16 and HPV 18 may contribute to reducing the cervical cancer burden in Trinidad.

OBJETIVO: Determinar la contribución relativa de los diferentes genotipos de virus de los papilomas humanos (VPH) conocidos como de alto riesgo para la aparición de cáncer cervicouterino en Trinidad. MÉTODOS: Se investigó la distribución de los genotipos de VPH en casos de carcinoma cervicouterino escamocelular invasor en Trinidad. Este estudio fue la continuación de una investigación de los genotipos de VPH presentes en 310 mujeres asintomáticas en Trinidad. Este último estudio reveló altas prevalencia de VPH en el cuello uterino y heterogeneidad de los genotipos en la población del estudio; cabe destacar que los genotipos a los que se dirigen las vacunas preventivas de la infección por VPH disponibles no fueron los tipos más frecuentes. RESULTADOS: El presente estudio, llevado a cabo en 85 casos de carcinoma cervicouterino escamocelular invasor, demostró que la heterogeneidad anteriormente observada en la distribución de genotipos de VPH no se mantiene en los casos de cáncer cervicouterino invasor, y que los tipos de VPH objeto de la vacuna, el VPH 16 y el VPH 18, pasan a ser los más prevalentes. CONCLUSIONES: En el presente estudio llevado a cabo en Trinidad, el VPH 16 y el VPH 18 fueron los principales genotipos de VPH asociados con los casos de carcinoma escamocelular invasor. Esta estrecha asociación nos lleva a la conclusión de que las vacunas contra el VPH dirigidas contra el VPH 16 y el VPH 18 pueden contribuir a la reducción de la carga de cáncer cervicouterino en Trinidad.

Novel microsphere-based method for detection and typing of 46 mucosal human papillomavirus types.

We have developed a novel microsphere-based genotyping method for 46 mucosal human papillomavirus (HPV) types. HPV DNA was amplified by PCR using general primers and typed by hybridization to HPV type-specific probes coupled to sortable microspheres based on the Luminex xMAP technology. Hybridization to each probe was specific for each HPV type without cross-hybridization and sensitive enough to allow typing of HPV contained in clinical specimens. The method was validated with direct sequencing and the Roche Linear Array genotyping method.