Measurement of measles virus-specific IgG is used to assess presumptive evidence of immunity among immunocompetent individuals with uncertain immune or vaccination status. False-negative test results may lead to unnecessary quarantine and exclusion from activities such as employment, education, and travel or result in unnecessary revaccination. In contrast, false-positive results may fail to identify susceptible individuals and promote spread of disease by those who are exposed and unprotected. To better understand the performance characteristics of tests to detect measles IgG, we compared five widely used, commercially available measles IgG test platforms using a set of 223 well-characterized serum samples.
Summary • Following the recommendation to introduce critical care outreach, two different models on two hospital sites were introduced within a large teaching Trust • To establish ward nurses' views and opinions of important components of the two outreach models, a questionnaire survey was undertaken involving 134 ward nurses on the awareness of outreach, accessibility of outreach and usage of outreach • The results identified a high level of user satisfaction amongst ward nurses. Awareness of critical care outreach and how to access the service within a hospital site was good, with little differences between the two different models. Outreach was found to provide ward nurses with better skills, more knowledge, advice and support • Providing a 24‐h service and continual critical care education and training opportunities are the suggested ways to improve outreach in the future
Abstract Laboratory confirmation of infection is an essential component of measles surveillance. Detection of measles specific IgM in serum by enzyme linked immunosorbent assay (ELISA) is the most used method for confirming measles infection. ELISA formats vary as does the sensitivity and specificity of each assay. Specimens collected within 3 days of rash onset can yield a false negative result, which can delay confirmation of measles cases. Interfering substances can yield a false positive result, leading to unnecessary public health interventions. The IgM capture assay developed at the Centers for Disease Control (CDC) was compared against 5 commercially available ELISA kits for the ability to detect measles virus-specific IgM in a panel of 90 well-characterized specimens. Serum samples were tested in triplicate using each commercial kit as recommended by the manufacturer. Using the CDC measles IgM capture assay as the reference test; sensitivity and specificity for the commercial kits ranged from 50 to 83% and 86.9 to 98%, respectively. Discrepant results were observed for samples tested with all five commercial kits and ranged from 13.8 to 28.8% of the specimens tested. False positive results occurred in 2.0 to 13.1% of sera while negative results were observed in 16.7 to 50% of sera that were positive by the CDC measles IgM capture assay. Evaluation and interpretation of measles IgM serologic results can be complex, particularly in measles elimination settings. The performance characteristics of a measles IgM assay should be carefully considered when selecting an assay to achieve high quality measles surveillance.
Abstract Triple-negative breast cancer is a heterogeneous disease with no approved targeted therapies. The disease course is very aggressive, characterized by relapse within 3 years of treatment and metastases to the viscera, including the brain. The prognosis in the setting of distant metastases is grim, as median survival is less than one year. Recently, insight into the molecular complexity of TNBC was provided by gene expression analysis, which identified six unique subtypes with distinct gene ontologies that differ with respect to drug sensitivity. These subtypes, each enriched in unique molecular components and pathways, suggest target-based strategies for treatment. A multiplicity of targeted drugs has entered clinical trials for the potential treatment of TNBC, but no uncontested victor has emerged that can appreciably extend overall survival. For instance, one of the most promising experimental drugs is iniparib, which significantly improved outcomes in a Phase II clinical trial of metastatic TNBC when combined with carboplatin/gemcitabine; however, overall survival was still unacceptably short at ~1 year. Therefore, there remains a dire need to identify novel therapeutic modalities for TNBC. A promising research strategy towards this goal is to determine the differential sensitivities of the TNBC molecular subtypes to combinations of cytotoxic and targeted drugs. We are determining the responses of a panel of TNBC cell lines representing different molecular subtypes, including the basal-like 1 (HCC1143 and MDA-MB-468), basal-like 2 (HCC1806 and HCC70), immunomodulatory (HCC1187), mesenchymal stem-like (MDA-MB-436, MDA-MB-231, and MDA-MB-157), and luminal androgen receptor (MFM-223) subtypes, to variable doses of carboplatin, capecitabine, cyclophosphamide, docetaxel, and everolimus, used alone and in combination. These drugs were chosen because they target molecular regulators of prominent signaling pathways specific to certain TNBC molecular subtypes, so we expect to find that sensitivity to these drugs is a function of subtype. The results of this study will enable characterization of TNBC subtypes in finer detail and provide a preclinical framework for the development of subtype-dependent regimens for TNBC treatment. Citation Format: Heather Colley, Roopali Saxena, Angela Ogden, Guilherme Cantuaria, Michelle D. Reid, Xiaoxian (Bill) Li, Uma Krishnamurthy, Padmashree CG Rida, Ritu Aneja. Sensitivity of triple-negative breast cancer cell lines to cytotoxic and targeted agents as a function of molecular subtype. [abstract]. In: Proceedings of the Eighth AACR Conference on The Science of Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; Nov 13-16, 2015; Atlanta, GA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2016;25(3 Suppl):Abstract nr C50.
Laboratory confirmation of infection is an essential component of measles surveillance. Detection of measles-specific IgM in serum by enzyme-linked immunosorbent assay (ELISA) is the most common method used to confirm measles infection. ELISA formats vary, as does the sensitivity and specificity of each assay. Specimens collected within 3 days of rash onset can yield a false-negative result, which can delay confirmation of measles cases. Interfering substances can yield a false-positive result, leading to unnecessary public health interventions. The IgM capture assay developed at the Centers for Disease Control (CDC) was compared against five commercially available ELISA kits for the ability to detect measles virus-specific IgM in a panel of 90 well-characterized specimens. Serum samples were tested in triplicate using each commercial kit as recommended by the manufacturer. Using the CDC measles IgM capture assay as the reference test; the sensitivity and specificity for each commercial kit ranged from 50 to 83% and 86.9 to 98%, respectively. Discrepant results were observed for samples tested with all five commercial kits and ranged from 13.8 to 28.8% of the specimens tested. False-positive results occurred in 2.0 to 13.1% of sera, while negative results were observed in 16.7 to 50% of sera that were positive by the CDC measles IgM capture assay. Evaluation and interpretation of measles IgM serologic results can be complex, particularly in measles elimination settings. The performance characteristics of a measles IgM assay should be carefully considered when selecting an assay to achieve high-quality measles surveillance.
On April 24, 2023, the American Samoa Department of Health (ASDoH) declared a public health emergency amid concern about a possible measles outbreak given low 2-dose vaccination coverage at the time. ASDoH had received two positive measles immunoglobulin (Ig) M test results after Flag Day festivities 1 week earlier from vaccinated children. ASDoH performed active case finding, took actions to mitigate transmission, and requested technical assistance from CDC. ASDoH implemented a vaccination campaign to improve suboptimal coverage. Confirmatory molecular testing of specimens from these initial persons under investigation (PUIs) was not possible, but subsequent testing of specimens from additional PUIs by Hawaii State Laboratories Division and CDC ruled out measles. In settings with low measles prevalence, measles antibody testing results have low positive predictive value and can lead to difficulties with interpreting results. Testing for additional pathogens revealed a variety of viruses known to cause common childhood viral exanthems. Both molecular and serologic testing should be performed for all suspected measles cases. To decrease the probability of false-positive IgM results, testing should be reserved for cases that meet the Council of State and Territorial Epidemiologists measles case definition, especially those in persons with no evidence of immunity and with a history of recent international travel. In addition, maintaining high measles vaccination coverage can prevent future outbreaks.
Abstract Background In 2017, a mumps outbreak occurred in a US military barracks. Serum collected at service entry was used to compare pre-exposure with presumptive vaccine-induced antibody levels from persons who developed mumps (cases) and potentially exposed persons who did not develop mumps (non-cases). Sufficient information to determine levels of exposure during the outbreak was not available. Methods Pre-outbreak serum samples from the Department of Defense Serum Repository were available from 254 potentially exposed service members. Twelve developed clinical symptoms and had post-outbreak serum collected. All sera were tested with a mumps-specific enzyme immunoassay for immunoglobulin M, immunoglobulin G (IgG), and IgG avidity. The neutralizing antibodies to vaccine strain (Jeryl Lynn [JL], genotype A) and wildtype virus (genotype G) was assessed by a plaque reduction neutralization test. A Fisher exact test and receiver operator characteristic curve were used to analyze the antibody response for non-cases and mumps cases. Results Eight mumps cases were laboratory confirmed. Pre-outbreak neutralizing antibody titers to JL and genotype G mumps virus and pre-outbreak IgG index values were proportionately lower for most cases as compared with exposed non-cases. When compared with potentially exposed non-cases, cases with clinical symptoms had greater odds of having a pre-outbreak JL titer <41 and a genotype G titer <16. Conclusions We identified potential correlates of protection for mumps neutralizing antibody titers against JL and genotype G mumps viruses.
