scholarly journals Roles of Host Species, Geographic Separation, and Isolation in the Seroprevalence of Jamestown Canyon and Snowshoe Hare Viruses in Newfoundland

2012 ◽  
Vol 78 (18) ◽  
pp. 6734-6740 ◽  
Author(s):  
Gregory Goff ◽  
Hugh Whitney ◽  
Michael A. Drebot
Keyword(s):  
Host Species ◽  
Neutralization Assay ◽  
Snowshoe Hare ◽  
Large Mammals ◽  
Content Type ◽  
Neuroinvasive Disease ◽  
Snowshoe Hares ◽  
Jamestown Canyon Virus ◽  
Geographic Separation ◽  
California Serogroup

ABSTRACTCalifornia serogroup viruses, including Jamestown Canyon virus (JCV) and snowshoe hare virus (SSHV), are mosquito-borne members of theBunyaviridaefamily and are endemic across North America. These arboviruses are potential pathogens which occasionally cause neuroinvasive disease in humans and livestock. A neutralization assay was used to document JCV and SSHV seroprevalence using blood collected from a variety of domestic and wildlife host species. These species were sampled in an island setting, Newfoundland, which contains diverse ecoregions, ecological landscapes, and habitats. Seroprevalence rates for each virus differed significantly among host species and within certain species across different geographic areas. JCV was significantly associated with large mammals, and SSHV was significantly associated with snowshoe hares. Seroprevalence rates in the 5 species of animals tested for prior exposure to JCV ranged from 0% in snowshoe hares to 64% in horses. Seroprevalence rates for SSHV ranged from less than 1% in bovines to 55% in all snowshoe hares. The seroprevalence of SSHV differed significantly (P< 0.05) among hares occupying the discrete habitats of watersheds separated by 14 to 35 km. Cattle on farms in boreal forest landscapes displayed significantly higher JCV seroprevalence (P< 0.001) than those on farms located in seacoast landscapes. Lifelong geographic isolation of cattle to insular Newfoundland was associated with significantly lower JCV seroprevalence (P< 0.01) than that for cattle which had lived off-island.

scholarly journals Cross reactivity of neutralizing antibodies to the encephalitic California Serogroup orthobunyaviruses varies by virus and genetic relatedness

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Alyssa B. Evans ◽  
Karin E. Peterson
Keyword(s):  
Gold Standard ◽  
Neutralizing Antibodies ◽  
Viral Encephalitis ◽  
Genetic Relatedness ◽  
Cross Reactivity ◽  
Etiologic Agent ◽  
Snowshoe Hare ◽  
Neuroinvasive Disease ◽  
California Serogroup ◽  
High Degree

AbstractThe California Serogroup (CSG) of Orthobunyaviruses comprises several viruses capable of causing neuroinvasive disease in humans, including La Crosse (LACV), Snowshoe Hare (SSHV), Tahyna (TAHV), Jamestown Canyon (JCV), and Inkoo (INKV) viruses. Diagnosis of specific CSG viruses is complicated by the high degree of antibody cross-reactivity between them, with laboratory standards requiring a fourfold higher titer of neutralizating antibody (NAb) activity to positively identify the etiologic virus. To help elucidate NAb relationships between neuroinvasive CSG viruses, we directly compared the cross-reactivity of NAb between LACV, SSHV, TAHV, JCV, and INKV. Mice were inoculated with individual viruses and the NAb activity of plasma samples was compared by plaque reduction neutralization tests against all five viruses. Overall, the results from these studies show that the CSG viruses induced high levels of NAb against the inoculum virus, and differing amounts of cross-reactive NAb against heterologous viruses. LACV, SSHV, and INKV elicited the highest amount of cross-reactive NAb. Interestingly, a fourfold difference in NAb titer between the inoculum virus and the other CSG viruses was not always observed. Thus, NAb titers, which are the gold-standard for diagnosing the etiologic agent for viral encephalitis, may not clearly differentiate between different CSG viruses.

scholarly journals Zoonotic Infections in Communities of the James Bay Cree Territory: An Overview of Seroprevalence

2013 ◽  
Vol 24 (2) ◽  
pp. 79-84 ◽  
Author(s):  
Hugues Sampasa-Kanyinga ◽  
Benoit Lévesque ◽  
Elhadji Anassour-Laouan-Sidi ◽  
Suzanne Côté ◽  
Bouchra Serhir ◽  
...  
Keyword(s):  
Diagnostic Testing ◽  
Toxocara Canis ◽  
Population Based ◽  
Sin Nombre Virus ◽  
Snowshoe Hare ◽  
James Bay ◽  
Zoonotic Infections ◽  
James Bay Cree ◽  
Jamestown Canyon Virus ◽  
California Serogroup

The Cree communities of James Bay are at risk for contracting infectious diseases transmitted by wildlife. Data from serological testing for a range of zoonotic infections performed in the general population (six communities), or trappers and their spouses (one community), were abstracted from four population-based studies conducted in Cree territory (Quebec) between 2005 and 2009. Evidence of exposure toTrichinellaspecies,Toxoplasma gondii,Toxocara canis,Echinococcus granulosus,Leptospiraspecies,Coxiella burnetiiandFrancisella tularensiswas verified in all communities, whereas antibodies against Sin Nombre virus and California serogroup viruses (Jamestown Canyon and snowshoe hare viruses) were evaluated in three and six communities, respectively. Seroprevalence varied widely among communities: snowshoe hare virus (1% to 42%),F tularensis(14% to 37%),Leptospiraspecies (10% to 27%), Jamestown Canyon virus (9% to 24%),C burnetii(0% to 18%),T gondii(4% to 12%),T canis(0% to 10%),E granulosus(0% to 4%) andTrichinellaspecies (0% to 1%). No subject had serological evidence of Sin Nombre virus exposure. These data suggest that large proportions of the Cree population have been exposed to at least one of the targeted zoonotic agents. The Cree population, particularly those most heavily exposed to fauna, as well as the medical staff living in these regions, should be aware of these diseases. Greater awareness would not only help to decrease exposures but would also increase the chance of appropriate diagnostic testing.

Jamestown Canyon and snowshoe hare virus seroprevalence in New Brunswick

2021 ◽  
pp. e20210009
Author(s):  
Jacqueline Mincer ◽  
Stefanie Materniak ◽  
Kristina Dimitrova ◽  
Heidi Wood ◽  
Mahmood Iranpour ◽  
...  
Keyword(s):  
Central Nervous System ◽  
New Brunswick ◽  
Human Exposure ◽  
Epidemiological Data ◽  
Enzyme Linked Immunosorbent Assay ◽  
Snowshoe Hare ◽  
Serum Samples ◽  
Jamestown Canyon Virus ◽  
Risk Of Exposure ◽  
California Serogroup

Background: Jamestown Canyon virus (JCV) and snowshoe hare virus (SSHV) are wide-ranging mosquito-borne arboviruses in the California serogroup viruses (CSGV) that are known to circulate in New Brunswick. Despite potential for debilitating central nervous system manifestations, the prevalence of human exposure to these viruses in New Brunswick is unknown. The goal of this study was to quantify rates of human exposure in New Brunswick to these neglected arboviruses. Methods: A retrospective, anonymized provincial serosurvey was performed using a stratified random sample of residual sera submitted between May 2015 and August 2016. To determine the seroprevalence of JCV and SSHV, competitive enzyme-linked immunosorbent assay–positive samples were confirmed positive using plaque-reduction neutralization testing (PRNT). Results: A total of 452 serum samples were screened. The seroprevalence of antibodies against CSGV was estimated to be 31.6% (95% CI 27.4% to 36.1%) with 143 positive samples. PRNT results indicated that most single virus exposures were due to JCV (38 of 143; 26.6%) rather than SSHV (3 of 143; 2.1%). The species of CSGV that the remaining 102 seropositive people were exposed to could not be precisely determined. Conclusions: The prevalence of human exposure to CSGV is high but comparable to rates observed in other Atlantic Canadian jurisdictions. Studies such as this provide important baseline epidemiological data regarding the risk of exposure to these neglected arboviruses. SSHV and JCV should be considered in the differential diagnosis for undiagnosed febrile and neuroinvasive illness during mosquito season, particularly when testing for common aetiologies is negative or inconclusive.

scholarly journals Use of a Toxin Neutralization Assay To Characterize the Serologic Response to Adenylate Cyclase Toxin after Infection with Bordetella pertussis

2016 ◽  
Vol 24 (1) ◽  
Author(s):  
Joshua C. Eby ◽  
Mary C. Gray ◽  
Jason M. Warfel ◽  
Tod J. Merkel ◽  
Erik L. Hewlett
Keyword(s):  
Adenylate Cyclase ◽  
Bordetella Pertussis ◽  
Neutralization Assay ◽  
Enzyme Linked Immunosorbent Assay ◽  
Immunologic Response ◽  
Serum Samples ◽  
Content Type ◽  
Adenylate Cyclase Toxin ◽  
Strong Candidate ◽  
Candidate Antigen

ABSTRACT Adenylate cyclase toxin (ACT) is an essential virulence factor of Bordetella pertussis, and antibodies to ACT protect against B. pertussis infection in mice. The toxin is therefore a strong candidate antigen for addition to future acellular pertussis vaccines. In order to characterize the functionality of the immunologic response to ACT after infection, we developed an assay for testing the ability of serum samples from subjects infected with B. pertussis to neutralize ACT-induced cytotoxicity in J774 macrophage cells. Baboons develop neutralizing anti-ACT antibodies following infection with B. pertussis, and all sera from baboons with positive anti-ACT IgG enzyme-linked immunosorbent assay (ELISA) results neutralized ACT cytotoxicity. The toxin neutralization assay (TNA) was positive in some baboon sera in which ELISA remained negative. Of serum samples obtained from humans diagnosed with pertussis by PCR, anti-ACT IgG ELISA was positive in 72%, and TNA was positive in 83%. All samples positive for anti-ACT IgG ELISA were positive by TNA, and none of the samples from humans without pertussis neutralized toxin activity. These findings indicate that antibodies to ACT generated following infection with B. pertussis consistently neutralize toxin-induced cytotoxicity and that TNA can be used to improve understanding of the immunologic response to ACT after infection or vaccination.

scholarly journals Microfluidic PCR Combined with Pyrosequencing for Identification of Allelic Variants with Phenotypic Associations among Targeted Salmonella Genes

2012 ◽  
Vol 78 (20) ◽  
pp. 7480-7482 ◽  
Author(s):  
Min Yue ◽  
Robert Schmieder ◽  
Robert A. Edwards ◽  
Shelley C. Rankin ◽  
Dieter M. Schifferli
Keyword(s):  
Genetic Variation ◽  
Antimicrobial Resistance ◽  
Host Species ◽  
Massive Parallel Sequencing ◽  
Allelic Variants ◽  
Parallel Sequencing ◽  
Content Type ◽  
Potential Applications ◽  
Fimbrial Adhesins ◽  
Diagnostic Microbiology

ABSTRACTA novel targeted massive parallel sequencing approach identified genetic variation in eight known or predicted fimbrial adhesins for 46Salmonellastrains. The results highlight associations between specific adhesin alleles, host species, and antimicrobial resistance. The differentiation of allelic variants has potential applications for diagnostic microbiology and epidemiological investigations.

scholarly journals High Agreement Between an Ultrasensitive Clostridioides difficile Toxin Assay and a C. difficile Laboratory Algorithm Utilizing GDH-and-Toxin Enzyme Immunoassays and Cytotoxin Testing

2019 ◽  
Vol 58 (2) ◽  
Author(s):  
Marie L. Landry ◽  
Jeffrey E. Topal ◽  
Joel Estis ◽  
Phoebe Katzenbach ◽  
Niamh Nolan ◽  
...  
Keyword(s):  
Standard Of Care ◽  
Neutralization Assay ◽  
High Agreement ◽  
Content Type ◽  
Clostridioides Difficile ◽  
Automated Assay ◽  
Toxin Assay ◽  
Stool Samples ◽  
Testing Algorithm ◽  
Positive Agreement

ABSTRACT The Singulex Clarity C. diff toxins A/B (Clarity) assay is an automated, ultrasensitive immunoassay for the detection of Clostridioides difficile toxins in stool. In this study, the performance of the Clarity assay was compared to that of a multistep algorithm using an enzyme immunoassay (EIA) for detection of glutamate dehydrogenase (GDH) and toxins A and B arbitrated by a semiquantitative cell cytotoxicity neutralization assay (CCNA). The performance of the assay was evaluated using 211 residual deidentified stool samples tested with a GDH-and-toxin EIA (C. Diff Quik Chek Complete; Techlab), with GDH-and-toxin discordant samples tested with CCNA. The stool samples were stored at –80°C before being tested with the Clarity assay. For samples discordant between Clarity and the standard-of-care algorithm, the samples were tested with PCR (Xpert C. difficile; Cepheid), and chart review was performed. The testing algorithm resulted in 34 GDH+/toxin+, 53 GDH−/toxin−, and 124 GDH+/toxin− samples, of which 39 were CCNA+ and 85 were CCNA−. Clarity had 96.2% negative agreement with GDH−/toxin− samples, 100% positive agreement with GDH+/toxin+ samples, and 95.3% agreement with GDH+/toxin−/CCNA− samples. The Clarity result was invalid for one sample. Clarity agreed with 61.5% of GDH+/toxin−/CCNA+ samples, 90.0% of GDH+/toxin−/CCNA+ (high-positive) samples, and 31.6% of GDH+/toxin−/CCNA+ (low-positive) samples. The Singulex Clarity C. diff toxins A/B assay demonstrated high agreement with a testing algorithm utilizing a GDH-and-toxin EIA and CCNA. This novel automated assay may offer an accurate, stand-alone solution for C. difficile infection (CDI) diagnostics, and further prospective clinical studies are merited.

scholarly journals Increased Clinical Specificity with Ultrasensitive Detection of Clostridioides difficile Toxins: Reduction of Overdiagnosis Compared to Nucleic Acid Amplification Tests

2019 ◽  
Vol 57 (11) ◽  
Author(s):  
Johanna Sandlund ◽  
Joel Estis ◽  
Phoebe Katzenbach ◽  
Niamh Nolan ◽  
Kirstie Hinson ◽  
...  
Keyword(s):  
Nucleic Acid ◽  
Patient Outcomes ◽  
Single Molecule ◽  
Clinical Performance ◽  
Neutralization Assay ◽  
Nucleic Acid Amplification ◽  
Content Type ◽  
Clostridioides Difficile ◽  
Health Care Associated Infections ◽  
Stool Specimens

ABSTRACT Clostridioides difficile infection (CDI) is one of the most common health care-associated infections, resulting in significant morbidity, mortality, and economic burden. Diagnosis of CDI relies on the assessment of clinical presentation and laboratory tests. We evaluated the clinical performance of ultrasensitive single-molecule counting technology for detection of C. difficile toxins A and B. Stool specimens from 298 patients with suspected CDI were tested with the nucleic acid amplification test (NAAT; BD MAX Cdiff assay or Xpert C. difficile assay) and Singulex Clarity C. diff toxins A/B assay. Specimens with discordant results were tested with the cell cytotoxicity neutralization assay (CCNA), and the results were correlated with disease severity and outcome. There were 64 NAAT-positive and 234 NAAT-negative samples. Of the 32 NAAT+/Clarity− and 4 NAAT−/Clarity+ samples, there were 26 CCNA− and 4 CCNA− samples, respectively. CDI relapse was more common in NAAT+/toxin+ patients than in NAAT+/toxin− and NAAT−/toxin− patients. The clinical specificity of Clarity and NAAT was 97.4% and 89.0%, respectively, and overdiagnosis was more than three times more common in NAAT+/toxin− than in NAAT+/toxin+ patients. The Clarity assay was superior to NAATs for the diagnosis of CDI, by reducing overdiagnosis and thereby increasing clinical specificity, and the presence of toxins was associated with negative patient outcomes.

scholarly journals Ultrasensitive Detection of Clostridioides difficile Toxins in Stool by Use of Single-Molecule Counting Technology: Comparison with Detection of Free Toxin by Cell Culture Cytotoxicity Neutralization Assay

2019 ◽  
Vol 57 (11) ◽  
Author(s):  
Glen Hansen ◽  
Stephen Young ◽  
Alan H. B. Wu ◽  
Emily Herding ◽  
Vickie Nordberg ◽  
...  
Keyword(s):  
Cell Culture ◽  
Single Molecule ◽  
Neutralization Assay ◽  
Single Step ◽  
Multicenter Studies ◽  
Content Type ◽  
Clostridioides Difficile ◽  
Ultrasensitive Assay ◽  
A Cell ◽  
Positive Agreement

ABSTRACT Laboratory tests for Clostridioides difficile infection (CDI) rely on the detection of free toxin or molecular detection of toxin genes. The Singulex Clarity C. diff toxins A/B assay is a rapid, automated, and ultrasensitive assay that detects C. difficile toxins A and B in stool. We compared CDI assays across two prospective multicenter studies to set a cutoff for the Clarity assay and to independently validate the performance compared with that of a cell culture cytotoxicity neutralization assay (CCCNA). The cutoff was set by two sites testing fresh samples from 897 subjects with suspected CDI and then validated at four sites testing fresh samples from 1,005 subjects with suspected CDI. CCCNA testing was performed at a centralized laboratory. Samples with discrepant results between the Clarity assay and CCCNA were retested with CCCNA when the Clarity result agreed with that of at least one comparator method; toxin enzyme immunoassays (EIA), glutamate dehydrogenase (GDH) detection, and PCR were performed on all samples. The cutoff for the Clarity assay was set at 12.0 pg/ml. Compared to results with CCCNA, the Clarity assay initially had 85.2% positive agreement and 92.4% negative agreement. However, when samples with discrepant results between the Clarity assay and CCCNA in the validation study were retested by CCCNA, 13/17 (76.5%) Clarity-negative but CCCNA-positive samples (Clarity+/CCCNA−) became CCCNA−, and 5/26 (19.2%) Clarity+/CCCNA− samples became CCCNA+, resulting in a 96.3% positive agreement and 93.0% negative agreement between Clarity and CCCNA results. The toxin EIA had 59.8% positive agreement with CCCNA. The Clarity assay was the most sensitive free-toxin immunoassay, capable of providing CDI diagnosis in a single-step solution. A different CCCNA result was reported for 42% of retested samples, increasing the positive agreement between Clarity and CCCNA from 85.2% to 96.3% and indicating the challenges of comparing free-toxin results to CCCNA results as a reference standard.

Impact of helminth parasitism on a snowshoe hare population in central Wisconsin: a field experiment

1995 ◽  
Vol 73 (10) ◽  
pp. 1891-1898 ◽  
Author(s):  
Sara E. M. Bloomer ◽  
Thomas Willebrand ◽  
Ingegerd M. Keith ◽  
Lloyd B. Keith
Keyword(s):  
Survival Rates ◽  
Snowshoe Hare ◽  
Marrow Fat ◽  
Proximate Cause ◽  
Risk Of Death ◽  
Snowshoe Hares ◽  
Condition Indices ◽  
Time Specific ◽  
And Control ◽  
Hare Population

We tested the hypothesis that helminth parasitism is demographically significant to a noncyclic population of snowshoe hares (Lepus americanus) near the species' geographic boundary in central Wisconsin (U.S.A.). During November 1988 to December 1991, we injected 93 individuals (≥760 g, aged ≥2 months) with anthelmintics: Ivermectin for nematode and Droncit for cestode infections. We injected 98 control hares with propylene glycol, the common vehicle for both drugs. All treated and control hares were radio-collared with mortality-sensing transmitters and monitored daily to weekly from the ground or air. Prevalence and intensity of lungworms (Protostrongylus boughtoni), intestinal worms (Nematodirus triangularis), and stomach worms (Obeliscoides cuniculi) were markedly reduced by Ivermectin treatment. No other nematodes were found to be present. Treatment with Droncit to remove intestinal cestodes was apparently unnecessary, as prevalence among necropsied untreated hares and controls was just 10%. We compared body-condition indices (mass changes, response to trap stress, and bone-marrow fat), reproduction (pregnancy rate and litter size), home-range sizes, and time-specific survival rates of anthelmintic-treated versus control hares. None of these demographic variables differed significantly between treated and control cohorts, nor was there any evidence that parasitism increased the risk of death from predation, which was the proximate cause of 96% of all natural mortalities. We conclude that helminth parasitism played no detectable role in the dynamics of this Wisconsin snowshoe hare population.

Attributes of forest strips used by snowshoe hare in winter within clear-cut boreal landscapes

2005 ◽  
Vol 35 (10) ◽  
pp. 2521-2527 ◽  
Author(s):  
François Potvin ◽  
Normand Bertrand ◽  
Jean Ferron
Keyword(s):  
Abies Balsamea ◽  
Basal Area ◽  
Balsam Fir ◽  
Snowshoe Hare ◽  
Forest Patches ◽  
Clear Cut ◽  
Important Prey ◽  
South Central ◽  
Snowshoe Hares ◽  
Riparian Strips

The snowshoe hare (Lepus americanus Erxleben) is an important prey for many predators in the boreal forest. In this biome, clear-cut landscapes are generally large and consist of aggregated cutting blocks separated by narrow forest strips (typically 60–100 m wide). To identify attributes of forest strips that are important for snowshoe hares, we measured the use of strips using track counts over two winters in six clear-cut landscapes (23–256 km2) in south-central Quebec. Surveys were conducted in 20 riparian strips (RS), 20 upland strips (US), and 15 control sites (CO) at the periphery of clear-cut landscapes. Overall, 392 signs of hare presence were recorded along 50 km of transects. Snowshoe hares were present in one-third of the strips surveyed and were five times less abundant in US and RS than in CO. The species avoided strip edges. Hares were more common in the wider strips (>100 m), in the strips adjacent to residual forest patches (≥25 ha), or in those having a denser shrub canopy, which is often associated with a greater basal area in balsam fir (Abies balsamea (L.) Mill.). To maintain snowshoe hare at moderate densities in large clear-cut landscapes, we suggest leaving uncut forest strips >100 m wide in areas having a good shrub cover with presence of balsam fir.

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