The added value of One Health surveillance: data from questing ticks can provide an early signal for anaplasmosis outbreaks in animals and humans.

OBJECTIVE: In 2021, a first outbreak of anaplasmosis occurred in animals and humans in southern Québec, with 64% of confirmed human cases located in Bromont municipality. Ixodes scapularis ticks and Peromyscus mouse ear biopsies collected in Bromont from 2019 to 2021 were analyzed for Anaplasma phagocytophilum (Ap) with the objective of determining whether an early environmental signal could have been detected before the outbreak. METHODS: Samples were collected for a concurrent study aiming to reduce Lyme disease risk. Between 2019 and 2021, up to 14 experimental sites were sampled for ticks and capture of small mammals took place on three sites in 2021. Samples were screened for Ap using multiplex real-time PCR, and genetic strains were identified using a single-nucleotide polymorphism assay. RESULTS: Analyses showed an increase of 5.7% in Ap prevalence in ticks (CI95: 1.5-9.9) between 2019 and 2020, i.e., one year before the outbreak. A majority of Ap-positive ticks were infected with the zoonotic strain (68.8%; CI95: 50.0-83.9) during the study period. In 2021, 2 of 59 captured Peromycus mice were positive for Ap, for a prevalence of 3.4% (CI95: 0.4-11.7). CONCLUSION: We conclude that data collected in Bromont could have provided an early signal for an anaplasmosis risk increasing in the targeted region. This is a reminder that integrated surveillance of tick-borne diseases through structured One Health programs, i.e. systematically integrating data from humans, animals and the environment, can provide useful and timely information for better preparedness and response in public health.

RéSUMé: OBJECTIF: En 2021, suivant une éclosion d'anaplasmoses chez les animaux et les humains dans le sud du Québec, des tiques de l'espèce Ixodes scapularis et des biopsies de souris Peromyscus spp. échantillonées à Bromont, la municipalité où 64 % des cas humains confirmés était localisé, ont été testées pour Anaplasma phagocytophilum (Ap) avec pour objectif de déterminer si un signal environnemental précoce d'augmentation du risque aurait pu être détecté avant l'éclosion. MéTHODE: L'échantillonnage a été réalisé dans le cadre d'une étude visant à réduire le risque de maladie de Lyme. De 2019 à 2021, 14 sites expérimentaux ont été échantillonnés pour les tiques. En 2021, trois sites ont été sélectionnés pour la capture des micromammifères. Les échantillons ont été testés pour la présence d'Ap à l'aide d'un PCR multiplex en temps réelle et les lignées génétiques ont été identifiées grâce à un test de polymorphisme mononucléotidique. RéSULTATS: Les analyses ont montré une augmentation de 5,7 % (IC95% : 1,5­9,9) de la prévalence de Ap entre 2019 et 2020, c'est-à-dire un an avant l'éclosion. Cette augmentation est associée à la présence d'une majorité d'Ap de la lignée zoonotique (68,8 %; IC95% : 50,0­83,9) sur l'ensemble de la période étudiée. En 2021, deux Peromycus spp. capturées sur 59 étaient positives pour Ap pour une prévalence de 3,4 % (IC95% : 0,4­11,7). CONCLUSION: Les données environnementales échantillonnées à Bromont auraient pu fournir un signal précoce de l'augmentation du risque d'anaplasmose dans la région. C'est un rappel que la surveillance intégrée des maladies transmises par les tiques inspirée de l'approche Une seule santé, intégrant systématiquement des données humaines, animales et environnementales, peut fournir des informations utiles et opportunes aux autorités de santé publique.

Widespread Exposure to Mosquitoborne California Serogroup Viruses in Caribou, Arctic Fox, Red Fox, and Polar Bears, Canada.

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.

Evaluation of a Commercial Culture-Free Neutralization Antibody Detection Kit for Severe Acute Respiratory Syndrome-Related Coronavirus-2 and Comparison With an Antireceptor-Binding Domain Enzyme-Linked Immunosorbent Assay.

BACKGROUND: Severe acute respiratory syndrome-related coronavirus 2 (SARS-CoV-2) surrogate neutralization assays that obviate the need for viral culture offer substantial advantages regarding throughput and cost. The cPass SARS-CoV-2 Neutralization Antibody Detection Kit (GenScript) is the first such commercially available assay that detects antibodies that block receptor-binding domain (RBD)/angiotensin-converting enzyme (ACE)-2 interaction. We aimed to evaluate cPass to inform its use and assess its added value compared with anti-RBD enzyme-linked immunosorbent assays (ELISAs). METHODS: Serum reference panels comprising 205 specimens were used to compare cPass to plaque-reduction neutralization test (PRNT) and a pseudotyped lentiviral neutralization (PLV) assay for detection of neutralizing antibodies. We assessed the correlation of cPass with an ELISA detecting anti-RBD immunoglobulin (Ig)G, IgM, and IgA antibodies at a single timepoint and across intervals from onset of symptoms of SARS-CoV-2 infection. RESULTS: Compared with PRNT-50, cPass sensitivity ranged from 77% to 100% and specificity was 95% to 100%. Sensitivity was also high compared with the pseudotyped lentiviral neutralization assay (93%; 95% confidence interval [CI], 85-97), but specificity was lower (58%; 95% CI, 48-67). Highest agreement between cPass and ELISA was for anti-RBD IgG (r = 0.823). Against the pseudotyped lentiviral neutralization assay, anti-RBD IgG sensitivity (99%; 95% CI, 94-100) was very similar to that of cPass, but overall specificity was lower (37%; 95% CI, 28-47). Against PRNT-50, results of cPass and anti-RBD IgG were nearly identical. CONCLUSIONS: The added value of cPass compared with an IgG anti-RBD ELISA was modest.

SARS-CoV-2 infection and transmission in the North American deer mouse.

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.

Practical guidance for clinical laboratories for SARS-CoV-2 serology testing.

The landscape of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) diagnostic testing is rapidly evolving. While serology testing has limited diagnostic capacity for acute infection, its role in providing population-based information on positivity rates and informing evidence-based decision making for public health recommendations is increasing. With the global availability of vaccines, there is increasing pressure on clinical laboratories to provide antibody screening and result interpretation for vaccinated and non-vaccinated individuals. Here we present the most up-to-date data on SARS-CoV-2 antibody timelines, including the longevity of antibodies, and the production and detection of neutralizing antibodies. Additionally, we provide practical guidance for clinical microbiology laboratories to both verify commercial serology assays and choose appropriate testing algorithms for their local populations.

Evaluation of commercial SARS-CoV-2 serological assays in Canadian public health laboratories.

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.