Cache Valley virus (CVV) is a mosquito‐borne RNA virus detected throughout North America, Central America and parts of South America. A limited number of human case reports have described severe illness. CVV infection has been associated with outbreaks of congenital defects in small ruminants in Canada and the United States. A scoping review was conducted to identify, characterize and summarize research on CVV, and to identify research gaps. A structured search was conducted in eight electronic databases, with additional search verification and grey literature investigation. All captured studies were independently appraised by two reviewers for relevance and data characterization. The review captured 143 relevant studies investigating CVV epidemiology (n = 104), pathogenesis (n = 37), viral characteristics (n = 24), transmission (n = 14), diagnostic test performance (n = 8) and mitigation strategies (n = 2). Evidence of CVV infection was found in mosquito studies (n = 47), and serological evidence of exposure was demonstrated in animals (n = 41), as well as human (n = 20) studies. In sheep, five outbreaks of birth defects following asymptomatic dam CVV infection during the first 50 days of pregnancy were reported. Only six human cases of CVV‐associated illness were captured, with case symptoms described as initially non‐specific, progressing to more severe clinical signs (e.g., meningitis). No research was identified investigating treatment, societal knowledge and risk perception, economic burden or predictive models related to the impact of climate change on CVV. CVV circulates in mosquito and animal species across a large area of the Americas. Small ruminants are the only animals in which CVV‐associated clinical disease has been extensively studied. It is likely that human cases are under‐reported or misdiagnosed. Future research should focus on the impact of CVV infection in human and animal populations.

Background: Observational and pupillographic studies of small numbers of normal subjects have shown that a small (<0.3 log units) relative afferent pupil defect (RAPD) is present in a minority. We have extended the investigation of the prevalence of RAPD to a larger number of normal subjects. Methods: A total of 102 subjects were examined by observation and pupillography. The swinging flashlight test was performed using neutral density filters for quantification. During the pupillographic procedure, light-emitting diodes were placed in front of each eye, alternately flashing for 2.5 seconds with a 0.5 second break. A binocular real-time pupillometer recorded the direct and consensual pupillary responses. After artefact detection and removal, the amplitudes of pupillary response were determined and plotted against stimulus intensity. The means of the direct and the consensual responses were used for automated calculation of RAPD. Results: By observation, there was no RAPD in 87 (85%) subjects; there was an RAPD of 0.15 log units in 13 (13%), and an RAPD of 0.3 log units in 2 (2%). By pupillography, there was an RAPD of 0.07 log units in 53 (52%) subjects, an RAPD between 0.08 and 0.22 log units in 43 (42%) subjects, and an RAPD between 0.23 and 0.39 log units in 6 (6%) subjects. Conclusions: Observation and pupillographic measurements of the swinging light test in a large normal subject cohort has confirmed that an RAPD is present in a small minority but that it does not exceed 0.39 log units. The RAPD in these subjects may be explained by inaccuracy of measurement or by asymmetries in the connections between visual pathways and pretectal nuclei in the midbrain.

Hepatitis E virus (HEV) has commonly been associated with large waterborne outbreaks of human jaundice in endemic areas but it has been increasingly recognised as a cause of sporadic human cases of jaundice in non-endemic areas, in individuals with no history of travel. Zoonotic exposure is widely hypothesized to be an important potential transmission route in these sporadic human cases. Serosurveys conducted to determine the frequency of HEV human exposure report wide ranges in prevalence across studies and locations. Our study objective was to compute meta-analysis summary estimates of human seroprevalence of HEV IgG within countries considered HEV non-endemic, where possible, and to determine whether this varied significantly across these countries, as well as investigating the role of potential HEV seroprevalence predictors such as population age structure. A broad literature search was conducted in six electronic databases. Citations were appraised, and relevant data extracted using forms designed and pre-tested a priori. Meta-analysis and meta-regression were conducted in R, with HEV IgG seroprevalence in blood donors or the general population being the outcome of interest, and country, assay, population age and sex structure, and chronological time investigated as predictors of the outcome. From 4163 unique citations initially captured, data were extracted from 135 studies investigating HEV serology in blood donors or the general population, of 31 countries among those categorised as ‘very high human development’ by the United Nations. Country of sampling and assay employed were consistently significant predictors of HEV IgG seroprevalence with chronological time being a non-significant predictor in the dataset of captured studies. While country of sampling and assay employed were significant predictors of HEV seroprevalence, comparison of HEV seroprevalence across non-endemic countries is hampered by the lack of a gold standard assay and uncertainty regarding residual bias across studies, as well as regional differences within some countries.

Background: The magnitude and knowledge gaps regarding antimicrobial use (AMU) and antimicrobial resistance (AMR) have not been summarized for the North American cow–calf production sector, although estimates of AMU and AMR are essential to AMR risk analysis. The objectives of this scoping review were to map AMU and AMR in the beef cow–calf sector in Canada and the United States, summarize published AMU/AMR predictors, and identify research gaps. Methods: An electronic search was conducted of four bibliographic databases and Google Scholar, augmented by a hand-search of captured studies. Results: Twenty-three of three-hundred and forty-three publications screened advanced to data extraction. Of these, 10 were conducted in the USA and 13 in Canada. Thirteen studied AMR and twelve studied AMU, with two reporting both. Of twelve captured AMU studies, nine presented counts of herd AMU by antimicrobial class or specific antimicrobial. Antimicrobial resistance in Escherichia coli (E. coli) was reported in nine studies. Risk factors for AMU include herd size, vaccine use, and start date of calving season. Conclusions: Overall, a small number of AMR studies were available for synthesis in primarily one population (cows) reporting E. coli AMR. Additional studies targeting reasons for AMU in calves, the impact of management procedures on AMU, potential environmental AMR sources, and AMR in respiratory pathogens and enteric organisms other than E. coli for pre-weaning calves are required to inform AMR risk mitigation strategies.