Orthoebolaviruses are non-segmented, negative sense RNA viruses that make up the genus Orthoebolavirus in the family Filoviridae. Sudan virus (SUDV) is a highly pathogenic orthoebolavirus that causes severe disease in humans. In the last 45 years, SUDV has been responsible for several outbreaks in eastern Africa, particularly in Sudan and Uganda, with an average case fatality rate of approximately 50%. Despite having caused numerous outbreaks, including a recent outbreak in 2022, no licensed therapeutics or prophylactics currently exist for Sudan virus disease. Small animal models like mice, hamsters, and guinea pigs have paved the way for the initial evaluation of filovirus countermeasures; however, since filoviruses are apathogenic in immunocompetent rodents, they must first be adapted through serial passaging. As a result of this process, viruses acquire genomic changes that may contribute to increased virulence and lethality. Currently, only a single immunocompetent small animal model exists for SUDV, where the virus was serially passaged in guinea pigs until uniform lethality was observed. To better understand the serial passaging process, we used next-generation sequencing to identify and quantify the mutations that arose throughout the adaptation process in guinea pigs. We identified 7 nonsynonymous and 9 synonymous mutations that were present at frequencies near 100% at the end of serial passaging. The glycoprotein and virion protein (VP) 40 harboured many of the substitutions, most of which were nonsynonymous, while VP35 and VP24 each maintained a single nonsynonymous mutation. These results are consistent with the previously determined genome sequence, obtained by Sanger sequencing, with two notable exceptions: we identified a novel mutation in VP40, but we were unable to confirm the mutation in the genome leader, due to poor sequence coverage. This analysis has allowed us to identify adaptive hotspots within the viral genome, which may hint at the molecular determinants contributing to pathogenicity.

Jamestown Canyon virus (JCV) is a mosquitoborne orthobunyavirus in the California serogroup that circulates throughout Canada and the United States. Most JCV exposures result in asymptomatic infection or a mild febrile illness, but JCV can also cause neurologic diseases, such as meningitis and encephalitis. We describe a case series of confirmed JCV-mediated neuroinvasive disease among persons from the provinces of British Columbia, Alberta, Quebec, and Nova Scotia, Canada, during 2011–2016. We highlight the case definitions, epidemiology, unique features and clinical manifestations, disease seasonality, and outcomes for those cases. Two of the patients (from Quebec and Nova Scotia) might have acquired JCV infections during travel to the northeastern region of the United States. This case series collectively demonstrates JCV's wide distribution and indicates the need for increased awareness of JCV as the underlying cause of meningitis/meningoencephalitis during mosquito season.

Northern Canada is warming at 3 times the global rate. Thus, changing diversity and distribution of vectors and pathogens is an increasing health concern. California serogroup (CSG) viruses are mosquitoborne arboviruses; wildlife reservoirs in northern ecosystems have not been identified. We detected CSG virus antibodies in 63% (95% CI 58%-67%) of caribou (n = 517), 4% (95% CI 2%-7%) of Arctic foxes (n = 297), 12% (95% CI 6%-21%) of red foxes (n = 77), and 28% (95% CI 24%-33%) of polar bears (n = 377). Sex, age, and summer temperatures were positively associated with polar bear exposure; location, year, and ecotype were associated with caribou exposure. Exposure was highest in boreal caribou and increased from baseline in polar bears after warmer summers. CSG virus exposure of wildlife is linked to climate change in northern Canada and sustained surveillance could be used to measure human health risks.

The extent of the COVID-19 pandemic will be better understood through serosurveys and SARS-CoV-2 antibody testing. Dried blood spot (DBS) samples will play a central role in large scale serosurveillance by simplifying biological specimen collection and transportation, especially in Canada. Direct comparative clinical performance data on multiplex SARS-CoV-2 assays resulting from identical DBS samples are currently lacking. In our study, we aimed to provide clinical performance data for the BioPlex 2200 SARS-CoV-2 IgG (Bio-Rad), V-PLEX SARS-CoV-2 Panel 2 IgG (MSD), and Elecsys Anti-SARS-CoV-2 (Roche) commercial assays, as well as for two highly scalable in-house assays (University of Ottawa and Mount Sinai Hospital protocols) to assess their suitability for DBS-based SARS-CoV-2 DBS serosurveillance. These assays were evaluated against identical panels of DBS samples collected from convalescent COVID-19 patients (n =97) and individuals undergoing routine sexually transmitted and bloodborne infection (STBBI) testing prior to the COVID-19 pandemic (n =90). Our findings suggest that several assays are suitable for serosurveillance (sensitivity >97% and specificity >98%) even in low prevalence settings. In contrast to other reports, we did not observe an improvement in clinical performance using multiple antigen consensus-based rules to establish overall seropositivity. This may be due to our DBS panel which consisted of samples collected from convalescent COVID-19 patients with significant anti-spike, -RBD, and nucleocapsid antibody titers. This study demonstrates that biological specimens collected as DBS coupled with one of several readily available assays are useful for large-scale COVID-19 serosurveillance nonetheless.Funding Information:Marc-Andre ́ Langlois (M.-A.L.) holds a Canada Research Chair in Molecular Virology and Intrinsic Immunity. This study was supported in part by a COVID-19 Rapid Response grant to M.-A. L. by the Canadian Institute of Health Research (CIHR; OV1-170355) and by a grant supplement by the COVID-19 Immunity Task Force (CITF). The authors did not receive a salary from any of the funders.Conflict of Interests:The authors have declared that no competing interests exist.Ethical Approval: ll experiments were carried out in accordance with relevant guidelines and regulations. Written informed consent was obtained from all participants who provided blood samples. All participants were 18 years of age or older. Ethical approval was obtained from the Health Canada and Public Health Agency of Canada Research Ethics Board (no. 2020-022P).

Top Abstracts from the 2021 Canadian Society of Transfusion Medicine (CSTM) Annual Meeting Each year, the Canadian Society for Transfusion Medicine (CSTM) selects the top four abstracts submitted to its annual scientific meeting. As a service to our friends at CSTM and to honor the investigators, Transfusion Medicine Reviews is pleased to publish the winning entries. We wish all the participants good luck in their research work. Loss of repeat convalescent plasma donors due to waning anti-SARS-CoV-2 plaque reduction neutralization test titers (April-December 2020) Steven Drews, Dana Devine, Janet McManus, Emelissa Mendoza, Kathy Manguiat, Roxie Girardin, Alan Dupuis, Kathleen McDonough, James Lin, David Evans, Chantale Pambrun, Michael Drebot, Heidi Wood Background: Canadian Blood Services (CBS) uses plaque reduction neutralization test 50 (PRNT50) results to enroll convalescent plasma donors and qualify each donation with respect to neutralizing antibody titer. The generated PRNT50 values are used to qualify convalescent plasma donations supporting clinical trials in Canada. We describe waning PRNT50 titers of repeat plasma donors. Methods: All donations met standard criteria for plasma donations. SARS-CoV-2 specific neutralizing antibody titers were determined using PRNT50 in Vero E6 cell cultures. Plasma units demonstrating initial and repeat titers of ≥1:160 (and ≥1:80 in December 2020) were issued to trial sites. Donors with titers of ≥1:160 on initial donation and ≥1:160 (or ≥1:80 as of December 2020) were encouraged to return for repeat donation as frequently as weekly. Donors with titers of 1:40 or 1:80 were asked to donate one additional time in hopes their titers reached an acceptable level. Data were stored in an Excel file and statistical analysis was undertaken using GraphPad Prism. Results: From April 29, 2020-December 27, 2020, there were 415 donations from 128 repeat donors making 2 or more donations. Of the repeat donors, 36.7% (47/128) showed a ≥ 8-fold decrease in PRNT50 titers from peak to trough. The median time from onset of symptoms to a ≥8-fold decrease in PRNT50 titers was 129 days (range 63-233 days). Regression analysis of titer versus time past resolution of symptoms indicated a significant relationship P = 0.0 0 03;Spearman r = -0.1788 with Gaussian approximation; confidence interval (-0.2720 to -0.08109). Conclusions: It is evident that blood operators cannot infer that SARS-CoV-2 PRNT50 titers will remain high in repeat plasma donors at each donation. In many donors, PRNT50 values will be substantially degraded four months after onset of COVID-19 symptoms. Operationally, this means that there will be a continual loss of convalescent plasma donors over time as their PRNT50 values decrease. Blood operators will need to consider approaches for identifying convalescent plasma donors with high titers and focusing on donor groups that may have sustained PRNT50 values over time from onset of symptoms. http://dx.doi.org/10.1016/j.tmrv.2021.10.004 Optimizing donor screening and eligibility for gbMSM and trans donors: Assessing current donors’ perceptions of alternative screening questions Jennie Haw, Hyunjin Woo, Taylor Kohut, William Fisher Introduction/objective Canadian Blood Services aims to optimize donor screening and eligibility for gay, bisexual, and other men who have sex with men (gbMSM) and trans donors. Implementing a gender-neutral, individual risk behaviour-based approach to screening all donors may be an equitable screening approach and enable more gbMSM and trans people to donate. This approach would require the addition of alternative sexual behaviour questions in the donor questionnaire (DQ). Research suggests, however, that donors may feel discomfort answering some sexual behaviour questions (e.g., "in the last 3 months, have you had a new sexual partner?", "in the last 3 months, have you had anal sex?") which may lead to donor loss. This project seeks to assess donor views on and understandings of alternative screening questions with an aim of identifying strategies to mitigate discomfort and minimize donor loss. Design and Methods The current presentation reports Phase 1 (qualitative) results of a 2-year mixed methods study. Semistructured interviews (n = 40) were conducted from Jan. 2021-March 2021. Participants were recruited using a purposive sampling strategy to maximize diversity according to sociodemographic characteristics including: gender, sexual orientation, ethnicity, age, region, and number of donations. All interviews were audio-recorded, transcribed verbatim, and inductive thematic analysis was conducted. Results Preliminary (note – interviews will be completed earlyMarch 2021)

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic galvanized blood donor seroprevalence studies, which continue to inform public health policy. We propose that the two Canadian blood suppliers, Héma-Québec and Canadian Blood Services, expand their role in public health surveillance in the post-pandemic period. Together blood suppliers have near-national reach, collecting blood donations nearly every day in all larger cities and many smaller municipalities. Blood donors are a healthy subset of the general population. Demographic data, routine infectious disease testing and screening questionnaire data are collected for all donations. Close to one million blood samples per year could be made available for surveillance. With 90% repeat donors, longitudinal sampling is possible. Current blood donor surveillance includes monitoring infectious marker rates in low risk (e.g. HIV, hepatitis C virus) or asymptomatic (e.g. West Nile virus) populations, and ad hoc studies to monitor transfusion-transmissible infections. These include tick-borne infections such as Babesia microti and foodborne infections such as hepatitis E. Canadian Blood Services and Héma-Québec are actively seeking to engage with public health professionals to further develop a role in public health surveillance.

La pandémie de coronavirus du syndrome respiratoire aigu sévère 2 (SRAS-CoV-2) a galvanisé les études de séroprévalence des donneurs de sang, qui continuent d’éclairer les politiques de santé publique. Nous proposons que les deux fournisseurs de sang canadiens, Héma-Québec et la Société canadienne du sang, élargissent leur rôle de surveillance de la santé publique en période postpandémique. Ensemble, les fournisseurs de sang ont une portée quasi nationale, puisqu’ils collectent des dons de sang presque tous les jours dans toutes les grandes villes et dans de nombreuses petites municipalités. Les donneurs de sang constituent un sous-ensemble sain de la population générale. Les données démographiques, les tests de routine des maladies infectieuses et les données du questionnaire de dépistage sont recueillis pour tous les dons. Près d’un million d’échantillons de sang par année pourraient être fournis pour la surveillance. Grâce à 90 % de donneurs réguliers, un échantillonnage longitudinal est possible. La surveillance actuelle des donneurs de sang comprend le suivi des taux de marqueurs infectieux dans les populations à faible risque (e.g. le VIH, le virus de l’hépatite C) ou asymptomatiques (e.g. le virus du Nil occidental), et des études ad hoc pour surveiller les infections transmissibles par transfusion. Il s’agit notamment d’infections transmises par les tiques, comme Babesia microti, et d’infections d’origine alimentaire, comme l’hépatite E. La Société canadienne du sang et Héma-Québec cherchent activement à établir un dialogue avec des professionnels de la santé publique afin d’étoffer leur rôle dans la surveillance de la santé publique.

Cache Valley virus (CVV) is a mosquitoborne virus that infects livestock and humans. We report results of surveillance for CVV in New York, USA, during 2000–2016; full-genome analysis of selected CVV isolates from sheep, horse, humans, and mosquitoes from New York and Canada; and phenotypic characterization of selected strains. We calculated infection rates by using the maximum-likelihood estimation method by year, region, month, and mosquito species. The highest maximum-likelihood estimations were for Anopheles spp. mosquitoes. Our phylogenetic analysis identified 2 lineages and found evidence of segment reassortment. Furthermore, our data suggest displacement of CVV lineage 1 by lineage 2 in New York and Canada. Finally, we showed increased vector competence of An. quadrimaculatus mosquitoes for lineage 2 strains of CVV compared with lineage 1 strains.

BACKGROUND:Serological assays designed to detect SARS-CoV-2 antibodies are being used in serological surveys and other specialized applications. As a result, and to ensure that the outcomes of serological testing meet high quality standards, evaluations are required to assess the performance of these assays and the proficiency of laboratories performing them.METHODS:A panel of 60 plasma/serum samples from blood donors who had reverse transcriptase-polymerase chain reaction (RT-PCR) confirmed SARS-CoV-2 infections and 21 SARS-CoV-2 negative samples were secured and distributed to interested laboratories within Canada (n = 30) and the United States (n = 1). Participating laboratories were asked to provide details on the diagnostic assays used, the platforms the assays were performed on, and the results obtained for each panel sample. Laboratories were blinded with respect to the expected outcomes.RESULTS:The performance of the different assays evaluated was excellent, with the high-throughput platforms of Roche, Ortho, and Siemens demonstrating 100% sensitivity. Most other high-throughput platforms had sensitivities of >93%, with the exception of the IgG assay using the Abbott ARCHITECT which had an average sensitivity of only 87%. The majority of the high-throughput platforms also demonstrated very good specificities (>97%).CONCLUSION:This proficiency study demonstrates that most of the SARS-CoV-2 serological assays utilized by provincial public health or hospital laboratories in Canada have acceptable sensitivity and excellent specificity.

The extent of the COVID-19 pandemic will be better understood through serosurveys and SARS-CoV-2 antibody testing. Dried blood spot (DBS) samples will play a central role in large scale serosurveillance by simplifying biological specimen collection and transportation, especially in Canada. Direct comparative performance data on multiplex SARS-CoV-2 assays resulting from identical DBS samples are currently lacking. In our study, we aimed to provide performance data for the BioPlex 2200 SARS-CoV-2 IgG (Bio-Rad), V-PLEX SARS-CoV-2 Panel 2 IgG (MSD), and Elecsys Anti-SARS-CoV-2 (Roche) commercial assays, as well as for two highly scalable in-house assays (University of Ottawa and Mount Sinai Hospital protocols) to assess their suitability for DBS-based SARS-CoV-2 DBS serosurveillance. These assays were evaluated against identical panels of DBS samples collected from convalescent COVID-19 patients (n = 97) and individuals undergoing routine sexually transmitted and bloodborne infection (STBBI) testing prior to the COVID-19 pandemic (n = 90). Our findings suggest that several assays are suitable for serosurveillance (sensitivity >97% and specificity >98%). In contrast to other reports, we did not observe an improvement in performance using multiple antigen consensus-based rules to establish overall seropositivity. This may be due to our DBS panel which consisted of samples collected from convalescent COVID-19 patients with significant anti-spike, -receptor binding domain (RBD), and -nucleocapsid antibody titers. This study demonstrates that biological specimens collected as DBS coupled with one of several readily available assays are useful for large-scale COVID-19 serosurveillance.

National West Nile virus (WNV) surveillance was established in partnership with the federal, provincial and territorial governments starting in 2000, with the aim to monitor the emergence and subsequent spread of WNV disease in Canada. As the disease emerged, national WNV surveillance continued to focus on early detection of WNV disease outbreaks in different parts of the country. In Canada, the WNV transmission season occurs from May to November. During the season, the system adopts a One Health approach to collect, integrate, analyze and disseminate national surveillance data on human, mosquito, bird and other animal cases. Weekly and annual reports are available to the public, provincial/territorial health authorities, and other federal partners to provide an ongoing national overview of WNV infections in Canada. While national surveillance allows a jurisdiction-by-jurisdiction comparison of data, it also helps to guide appropriate disease prevention strategies such as education and awareness campaigns at the national level. This paper aims to describe both the establishment and the current structure of national WNV surveillance in Canada.

Volume 9, no. 3, e00886-21, 2021, https://doi.org/10.1128/Spectrum.00886-21. Page 1: This article was published on 17 November 2021 with David H. Evans missing from the byline. The byline was updated in the version posted on 11 February 2022.

Better diagnostic tools are needed to combat the ongoing COVID-19 pandemic. Here, to meet this urgent demand, we report a homogeneous immunoassay to detect IgG antibodies against SARS-CoV-2. This serological assay, called SATiN, is based on a tri-part Nanoluciferase (tNLuc) approach, in which the spike protein of SARS-CoV-2 and protein G, fused respectively to two different tNLuc tags, are used as antibody probes. Target engagement of the probes allows reconstitution of a functional luciferase in the presence of the third tNLuc component. The assay is performed directly in the liquid phase of patient sera and enables rapid, quantitative and low-cost detection. We show that SATiN has a similar sensitivity to ELISA, and its readouts are consistent with various neutralizing antibody assays. This proof-of-principle study suggests potential applications in diagnostics, as well as disease and vaccination management.

Widespread circulation of SARS-CoV-2 in humans raises the theoretical risk of reverse zoonosis events with wildlife, reintroductions of SARS-CoV-2 into permissive nondomesticated animals. Here we report that North American deer mice ( Peromyscus maniculatus ) are susceptible to SARS-CoV-2 infection following intranasal exposure to a human isolate, resulting in viral replication in the upper and lower respiratory tract with little or no signs of disease. Further, shed infectious virus is detectable in nasal washes, oropharyngeal and rectal swabs, and viral RNA is detectable in feces and occasionally urine. We further show that deer mice are capable of transmitting SARS-CoV-2 to naïve deer mice through direct contact. The extent to which these observations may translate to wild deer mouse populations remains unclear, and the risk of reverse zoonosis and/or the potential for the establishment of Peromyscus rodents as a North American reservoir for SARS-CoV-2 remains unknown.

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, to which the remaining 102 seropositive people were exposed, 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.

In March 2021, following the annual International Committee on Taxonomy of Viruses (ICTV) ratification vote on newly proposed taxa, the phylum Negarnaviricota was amended and emended. The phylum was expanded by four families (Aliusviridae, Crepuscuviridae, Myriaviridae, and Natareviridae), three subfamilies (Alpharhabdovirinae, Betarhabdovirinae, and Gammarhabdovirinae), 42 genera, and 200 species. Thirty-nine species were renamed and/or moved and seven species were abolished. This article presents the updated taxonomy of Negarnaviricota as now accepted by the ICTV.

The COVID-19 pandemic has led to the influx of immunoassays for the detection of antibodies towards severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) into the global market. The Canadian Public Health Laboratory Network Serology Task Force undertook a nationwide evaluation of twelve laboratory and 6 point-of-care based commercial serological assays for the detection of SARS-CoV-2 antibodies. We determined that there was considerable variability in the performance of individual tests and that an orthogonal testing algorithm should be prioritized to maximize the accuracy and comparability of results across the country. The manual enzyme immunoassays and point-of-care tests evaluated had lower specificity and increased coefficients of variation compared to automated enzyme immunoassays platforms putting into question their utility for large-scale sero-surveillance. Overall, the data presented here provide a comprehensive approach for applying accurate serological assays for longitudinal sero-surveillance and vaccine trials while informing Canadian public health policy.