Evolution of Diagnostic Tests for Chronic Wasting Disease, a Naturally Occurring Prion Disease of Cervids

Citation: Haley, N.J.; Richt, J.A. Evolution of Diagnostic Tests for Chronic Wasting Disease, a Naturally Occurring Prion Disease of Cervids. Pathogens 2017, 6, 35.Since chronic wasting disease (CWD) was first identified nearly 50 years ago in a captive mule deer herd in the Rocky Mountains of the United States, it has slowly spread across North America through the natural and anthropogenic movement of cervids and their carcasses. As the endemic areas have expanded, so has the need for rapid, sensitive, and cost effective diagnostic tests—especially those which take advantage of samples collected antemortem. Over the past two decades, strategies have evolved from the recognition of microscopic spongiform pathology and associated immunohistochemical staining of the misfolded prion protein to enzyme-linked immunoassays capable of detecting the abnormal prion conformer in postmortem samples. In a history that parallels the diagnosis of more conventional infectious agents, both qualitative and real-time amplification assays have recently been developed to detect minute quantities of misfolded prions in a range of biological and environmental samples. With these more sensitive and semi-quantitative approaches has come a greater understanding of the pathogenesis and epidemiology of this disease in the native host. Because the molecular pathogenesis of prion protein misfolding is broadly analogous to the misfolding of other pathogenic proteins, including Aβ and α-synuclein, efforts are currently underway to apply these in vitro amplification techniques towards the diagnosis of Alzheimer’s disease, Parkinson’s disease, and other proteinopathies. Chronic wasting disease—once a rare disease of Colorado mule deer—now represents one of the most prevalent prion diseases, and should serve as a model for the continued development and implementation of novel diagnostic strategies for protein misfolding disorders in the natural host

BSE Case Associated with Prion Protein Gene Mutation

Bovine spongiform encephalopathy (BSE) is a transmissible spongiform encephalopathy (TSE) of cattle and was first detected in 1986 in the United Kingdom. It is the most likely cause of variant Creutzfeldt-Jakob disease (CJD) in humans. The origin of BSE remains an enigma. Here we report an H-type BSE case associated with the novel mutation E211K within the prion protein gene (Prnp). Sequence analysis revealed that the animal with H-type BSE was heterozygous at Prnp nucleotides 631 through 633. An identical pathogenic mutation at the homologous codon position (E200K) in the human Prnp has been described as the most common cause of genetic CJD. This finding represents the first report of a confirmed case of BSE with a potential pathogenic mutation within the bovine Prnp gene. A recent epidemiological study revealed that the K211 allele was not detected in 6062 cattle from commercial beef processing plants and 42 cattle breeds, indicating an extremely low prevalence of the E211K variant (less than 1 in 2000) in cattle

Novel Swine Influenza Virus Subtype H3N1, United States

A new subtype H3N1 may have arisen from reassortment of a H3N2 turkey isolate, a human H1N1 isolate, and currently circulating swine viruses

Evaluation of two sets of immunohistochemical and Western blot confirmatory methods in the detection of typical and atypical BSE cases

<p>Abstract</p> <p>Background</p> <p>Three distinct forms of bovine spongiform encephalopathy (BSE), defined as classical (C-), low (L-) or high (H-) type, have been detected through ongoing active and passive surveillance systems for the disease.</p> <p>The aim of the present study was to compare the ability of two sets of immunohistochemical (IHC) and Western blot (WB) BSE confirmatory protocols to detect C- and atypical (L- and H-type) BSE forms.</p> <p>Obex samples from cases of United States and Italian C-type BSE, a U.S. H-type and an Italian L-type BSE case were tested in parallel using the two IHC sets and WB methods.</p> <p>Results</p> <p>The two IHC techniques proved equivalent in identifying and differentiating between C-type, L-type and H-type BSE. The IHC protocols appeared consistent in the identification of PrP^Scdistribution and deposition patterns in relation to the BSE type examined. Both IHC methods evidenced three distinct PrP^Scphenotypes for each type of BSE: prevailing granular and linear tracts pattern in the C-type; intraglial and intraneuronal deposits in the H-type; plaques in the L-type.</p> <p>Also, the two techniques gave comparable results for PrP^Scstaining intensity on the C- and L-type BSE samples, whereas a higher amount of intraglial and intraneuronal PrP^Scdeposition on the H-type BSE case was revealed by the method based on a stronger demasking step.</p> <p>Both WB methods were consistent in identifying classical and atypical BSE forms and in differentiating the specific PrP^Scmolecular weight and glycoform ratios of each form.</p> <p>Conclusions</p> <p>The study showed that the IHC and WB BSE confirmatory methods were equally able to recognize C-, L- and H-type BSE forms and to discriminate between their different immunohistochemical and molecular phenotypes. Of note is that for the first time one of the two sets of BSE confirmatory protocols proved effective in identifying the L-type BSE form. This finding helps to validate the suitability of the BSE confirmatory tests for BSE surveillance currently in place.</p

Effect of mixing and feed batch sequencing on the prevalence and distribution of African swine fever virus in swine feed

It is critical to have methods that can detect and mitigate the risk of African swine fever virus (ASFV) in potentially contaminated feed or ingredients bound for the United States. The purpose of this work was to evaluate feed batch sequencing as a mitigation technique for ASFV contamination in a feed mill, and to determine if a feed sampling method could identify ASFV following experimental inoculation. Batches of feed were manufactured in a BSL-3Ag room at Kansas State University's Biosafety Research Institute in Manhattan, Kansas. First, the pilot feed manufacturing system mixed, conveyed, and discharged an ASFV-free diet. Next, a diet was manufactured using the same equipment, but contained feed inoculated with ASFV for final concentration of 5.6 × 104 TCID50/g. Then, four subsequent ASFV-free batches of feed were manufactured. After discharging each batch into a collection container, 10 samples were collected in a double ‘X’ pattern. Samples were analysed using a qPCR assay for ASFV p72 gene then the cycle threshold (Ct) and Log10 genomic copy number (CN)/g of feed were determined. The qPCR Ct values (p < .0001) and the Log10 genomic CN/g (p < .0001) content of feed samples were impacted based on the batch of feed. Feed samples obtained after manufacturing the ASFV-contaminated diet contained the greatest amounts of ASFV p72 DNA across all criteria (p < .05). Quantity of ASFV p72 DNA decreased sequentially as additional batches of feed were manufactured, but was still detectable after batch sequence 4. This subsampling method was able to identify ASFV genetic material in feed samples using p72 qPCR. In summary, sequencing batches of feed decreases concentration of ASFV contamination in feed, but does not eliminate it. Bulk ingredients can be accurately evaluated for ASFV contamination by collecting 10 subsamples using the sampling method described herein. Future research is needed to evaluate if different mitigation techniques can reduce ASFV feed contamination

Evaluating the distribution of African swine fever virus within a feed mill environment following manufacture of inoculated feed

11 Pág. Centro de Investigación en Sanidad Animal (CISA)It is critical to understand the role feed manufacturing may have regarding potential African swine fever virus (ASFV) transmission, especially given the evidence that feed and/or ingredients may be potential vectors. The objective of the study was to evaluate the distribution of ASFV in a feed mill following manufacture of contaminated feed. To accomplish this, a pilot-scale feed mill consisting of a mixer, bucket elevator, and spouting was constructed in a BSL-3Ag facility. First, a batch of ASFV-free feed was manufactured, followed by a batch of feed that had an ASFV-contaminated ingredient added to feed, which was then mixed and discharged from the equipment. Subsequently, four additional ASFV-free batches of feed were manufactured using the same equipment. Environmental swabs from 18 locations within the BSL-3Ag room were collected after each batch of feed was discharged. The locations of the swabs were categorized into four zones: 1) feed contact surface, 2) non-feed contact surface 1 meter from feed, and 4) transient surfaces. Environmental swabs were analyzed using a qPCR specific for the ASFV p72 gene and reported as genomic copy number (CN)/mL of environmental swab processing buffer. Genomic copies were transformed with a log10 function for statistical analysis. There was no evidence of a zone × batch interaction for log10 genomic CN/mL (P = 0.625) or cycle threshold (Ct) value (P = 0.608). Sampling zone impacted the log10 p72 genomic CN/mL (P < 0.0001) and Ct values (P < 0.0001), with a greater amount of viral genome detected on transient surfaces compared to other surfaces (P < 0.05). This study illustrates that once ASFV enters the feed mill environment it becomes widespread and movement of people can significantly contribute to the spread of ASFV in a feed mill environment.Funding for this work was obtained from the NBAF Transition Funds from the state of Kansas (JAR), the National Pork Board under award number 20-018 (CKJ), the Department of Homeland Security Center of Excellence for Emerging and Zoonotic Animal Diseases under grant number HSHQDC 16-A-B0006 (JAR), and the AMP Core of the NIGMS COBRE Center on Emerging and Zoonotic Infectious Diseases (CEZID) under award number P20GM13044 (JAR)Peer reviewe

Detection of Respiratory Viruses and Subtype Identification of Influenza A Viruses by GreeneChipResp Oligonucleotide Microarray

Acute respiratory infections are significant causes of morbidity, mortality, and economic burden worldwide. An accurate, early differential diagnosis may alter individual clinical management as well as facilitate the recognition of outbreaks that have implications for public health. Here we report on the establishment and validation of a comprehensive and sensitive microarray system for detection of respiratory viruses and subtyping of influenza viruses in clinical materials. Implementation of a set of influenza virus enrichment primers facilitated subtyping of influenza A viruses through the differential recognition of hemagglutinins 1 through 16 and neuraminidases 1 through 9. Twenty-one different respiratory virus species were accurately characterized, including a recently identified novel genetic clade of rhinovirus.Fil: Quan, Phenix-Lan. Columbia University. Jerome L. and Dawn Greene Infectious Disease Laboratory; Estados Unidos.Fil: Palacios, Gustavo. Columbia University. Jerome L. and Dawn Greene Infectious Disease Laboratory; Estados Unidos.Fil: Jabado, Omar J. Columbia University. Jerome L. and Dawn Greene Infectious Disease Laboratory; Estados Unidos.Fil: Conlan, Sean. Columbia University. Jerome L. and Dawn Greene Infectious Disease Laboratory; Estados Unidos.Fil: Hirschberg, David L. Stanford School of Medicine; Estados Unidos.Fil: Pozo, Francisco. Instituto de Salud Carlos III. Centro Nacional de Microbiología; España.Fil: Jack, Philippa J. M. Australian Animal Health Laboratory. CSIRO Livestock Industries; Australia.Fil: Cisterna, Daniel. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas; Argentina.Fil: Renwick, Neil. Columbia University. Jerome L. and Dawn Greene Infectious Disease Laboratory; Estados Unidos.Fil: Hui, Jeffrey. Columbia University. Jerome L. and Dawn Greene Infectious Disease Laboratory; Estados Unidos.Fil: Drysdale, Andrew. Columbia University. Jerome L. and Dawn Greene Infectious Disease Laboratory; Estados Unidos.Fil: Amos-Ritchie, Rachel. Australian Animal Health Laboratory. CSIRO Livestock Industries; Australia.Fil: Baumeister, Elsa. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas; Argentina.Fil: Savy, Vilma. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas; Argentina.Fil: Lager, Kelly M. USDA. National Animal Disease Center; Estados Unidos.Fil: Richt, Jürgen A. USDA. National Animal Disease Center; Estados Unidos.Fil: Boyle, David B. Australian Animal Health Laboratory. CSIRO Livestock Industries; Australia.Fil: García-Sastre, Adolfo. Mount Sinai School of Medicine. Department of Microbiology and Emerging Pathogens Institute; Estados Unidos.Fil: Casas, Inmaculada. Instituto de Salud Carlos III. Centro Nacional de Microbiología; España.Fil: Perez-Breña, Pilar. Instituto de Salud Carlos III. Centro Nacional de Microbiología; España.Fil: Briese, Thomas. Columbia University. Jerome L. and Dawn Greene Infectious Disease Laboratory; Estados Unidos.Fil: Lipkin, W. Ian. Columbia University. Jerome L. and Dawn Greene Infectious Disease Laboratory; Estados Unidos

Detection of Respiratory Viruses and Subtype Identification of Influenza A Viruses by GreeneChipResp Oligonucleotide Microarray

Acute respiratory infections are significant causes of morbidity, mortality, and economic burden worldwide. An accurate, early differential diagnosis may alter individual clinical management as well as facilitate the recognition of outbreaks that have implications for public health. Here we report on the establishment and validation of a comprehensive and sensitive microarray system for detection of respiratory viruses and subtyping of influenza viruses in clinical materials. Implementation of a set of influenza virus enrichment primers facilitated subtyping of influenza A viruses through the differential recognition of hemagglutinins 1 through 16 and neuraminidases 1 through 9. Twenty-one different respiratory virus species were accurately characterized, including a recently identified novel genetic clade of rhinovirus.Fil: Quan, Phenix-Lan. Columbia University. Jerome L. and Dawn Greene Infectious Disease Laboratory; Estados Unidos.Fil: Palacios, Gustavo. Columbia University. Jerome L. and Dawn Greene Infectious Disease Laboratory; Estados Unidos.Fil: Jabado, Omar J. Columbia University. Jerome L. and Dawn Greene Infectious Disease Laboratory; Estados Unidos.Fil: Conlan, Sean. Columbia University. Jerome L. and Dawn Greene Infectious Disease Laboratory; Estados Unidos.Fil: Hirschberg, David L. Stanford School of Medicine; Estados Unidos.Fil: Pozo, Francisco. Instituto de Salud Carlos III. Centro Nacional de Microbiología; España.Fil: Jack, Philippa J. M. Australian Animal Health Laboratory. CSIRO Livestock Industries; Australia.Fil: Cisterna, Daniel. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas; Argentina.Fil: Renwick, Neil. Columbia University. Jerome L. and Dawn Greene Infectious Disease Laboratory; Estados Unidos.Fil: Hui, Jeffrey. Columbia University. Jerome L. and Dawn Greene Infectious Disease Laboratory; Estados Unidos.Fil: Drysdale, Andrew. Columbia University. Jerome L. and Dawn Greene Infectious Disease Laboratory; Estados Unidos.Fil: Amos-Ritchie, Rachel. Australian Animal Health Laboratory. CSIRO Livestock Industries; Australia.Fil: Baumeister, Elsa. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas; Argentina.Fil: Savy, Vilma. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas; Argentina.Fil: Lager, Kelly M. USDA. National Animal Disease Center; Estados Unidos.Fil: Richt, Jürgen A. USDA. National Animal Disease Center; Estados Unidos.Fil: Boyle, David B. Australian Animal Health Laboratory. CSIRO Livestock Industries; Australia.Fil: García-Sastre, Adolfo. Mount Sinai School of Medicine. Department of Microbiology and Emerging Pathogens Institute; Estados Unidos.Fil: Casas, Inmaculada. Instituto de Salud Carlos III. Centro Nacional de Microbiología; España.Fil: Perez-Breña, Pilar. Instituto de Salud Carlos III. Centro Nacional de Microbiología; España.Fil: Briese, Thomas. Columbia University. Jerome L. and Dawn Greene Infectious Disease Laboratory; Estados Unidos.Fil: Lipkin, W. Ian. Columbia University. Jerome L. and Dawn Greene Infectious Disease Laboratory; Estados Unidos