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The simultaneous concentration and recovery of microbes in drinking water is important for responding to potential water-related events such as pathogen contamination or bioterrorism and could be a cost-effective technique for routine monitoring of drinking water quality. Scientists at the CDC have combined two techniques, ultrafiltration (UF) and insulator-based dielectrophoresis (iDEP) in series, to achieve significant concentration of microbes and pathogens for analysis.

CDC researchers have engineered West Nile/dengue virus (WN/DENV) chimeras utilizing the replicative ability of the West Nile (WN) virus but presenting the immunogenic pre-membrane and envelope surface proteins of each of the four dengue virus serotypes (DENV 1-4). When coupled with a fluorescent reporter gene, each chimera is able to generate live chimeric reporter WN/DENV (R-WN/DENV) expressing the fluorescent protein in infected cells. These chimeric reporter viruses (CRVs) are used to develop faster and less hands-on high throughput neutralization assays for DENV.

Zika virus (ZIKV) is a flavivirus primarily transmitted by infected Aedes mosquitoes. Infection with ZIKV during pregnancy can affect the fetus causing microcephaly, neurological complications, and other birth defects. Adults are also at risk of developing Guillain-Barre syndrome and other neurological disorders from ZIKV infection. In response to the 2015-2016 Zika outbreak, CDC researchers developed new Zika virus chimeras that can be used for inactivated Zika vaccine candidates and faster Zika antibody (Ab) neutralization assay testing.

Currently available identification methods for antigen-specific antibodies require live pathogens, antisera (that are only available for a limited number of species), and species-specific secondary antibodies (also a limited resource). Thus, detection or surveillance of pathogens in wild avian species or zoo animals, for example, is complex and cumbersome.

Following primary dengue virus (DENV) infection, non-structural protein 1 (NS1), a dengue-specific glycoprotein, is present in blood and is easily detected by various assays. However, for any infection thereafter (secondary infection), bioavailability of the glycoprotein greatly reduces sensitivity of DENV detection. Since secondary DENV infection is a risk factor for developing hemorrhagic fever, there is increasing need for more sensitive detection at this stage.

CDC researchers have developed a novel method that generates globally amplified DNA copies retaining parental methylation information; making accurate DNA-archiving for methylation studies much more feasible and cost-effective than undertaking such an endeavor with alternate technologies. This unique approach eliminates a significant bottleneck in the collection of methylation information in the genome(s) of an individual organism, hosts and pathogens.

CDC scientists have developed recombinant flavivirus nucleic acids for the generation of broad protective immunity against flaviviruses, as well as the development of sensitive serologic diagnostic tools. Mosquito borne viral encephalitis is often caused by a flavivirus, such as Japanese encephalitis virus, dengue virus or West Nile virus. Infection by these pathogens is often lethal to both humans and animals.

This CDC developed optimization technology allows one to characterize the behavior of the coefficient of variation (CV) for a range of mass spectrometer machine settings. Surface-enhanced laser desorption/ionization (SELDI) and matrix-assisted laser desorption/ionization (MALDI) are used for the early detection of numerous diseases, for example cervical cancer . A critical step in the analytical process is the optimization of experiment and machine settings to ensure the best possible reproducibility of results, as measured by the CV.

CDC researchers have developed a multiplexed diagnostic assay for sensitive detection and distinction between viral group members based on the presence/absence of infection-generated antibodies within a clinical serum sample. For example, this assay can be used for rapid discrimination of a clinical unknown as specifically a West Nile or St. Louis encephalitis viral infection. This is particularly beneficial as these two viruses are typically difficult to distinguish by standard serological assays.

This new technique uses microsphere/microbead-based flow-analysis as a platform.

This invention provides a rapid, sensitive and specific diagnostic tool for the detection of pathogenic fungi and subsequent species-specific discrimination. CDC scientists have developed nucleic acid probes to identify the six most medically important Candida species and endemic mycoses, and to differentiate them from other medically important fungi in a multi-analyte profiling system.