Immunology of Physical Exercise: Is Equus caballus an Appropriate Animal Model for Human Athletes?

Domestic horses routinely participate in vigorous and various athletic activities. This enables the horse to serve as a model for studying athletic physiology and immunology in other species, including humans. For instance, as a model of physical efforts, such as endurance rides (long-distance running/aerobic exercise) and races (anaerobic exercise), the horse can be useful in evaluating post-exercise response. Currently, there has been significant interest in finding biomarkers, which characterize the advancement of training and adaptation to physical exercise in the horse. The parallels in cellular responses to physical exercises, such as changes in receptor expression and blood cell activity, improve our understanding of the mechanisms involved in the body's response to intense physical activity. This study focuses on the changes in levels of the pro- and anti-inflammatory cytokines and cellular response in the context of post-exercise immune response. Both the direction of changes in cytokine levels and cellular responses of the body, such as proliferation and expression of surface markers on lymphocytes, monocytes and neutrophils, show cross-functional similarities. This review reveals that horses are robust research models for studying the immune response to physical exercise in human athletes.

Intranasal Dexmedetomidine Use in Pediatric Patients for Anxiolysis in the Emergency Department.

OBJECTIVES: In recent years, dexmedetomidine has gained traction as a treatment for anxiolysis in the emergency department (ED). When used with an atomizer, it may also be given intranasally for anxiolysis. The primary objective was to determine the level of ED provider satisfaction and comfort with intranasal (IN) dexmedetomidine for anxiolysis in pediatric patients with behavioral agitation and/or acute psychosis. The secondary objectives included determining safety, rates of therapy failure, and ED length of stay compared with oral midazolam. The efficacy of IN dexmedetomidine versus oral midazolam in patients with autism spectrum disorder (ASD) was also evaluated. METHODS: This was a single-center, prospective study in a pediatric ED from March 1 to December 31, 2021. Patients were included in the study if the ED provider requested IN dexmedetomidine anxiolysis and completed a postadministration survey. Safety and efficacy outcomes were assessed by chart review and compared with patients who received oral midazolam during the same study period. Efficacy was defined as the rate of treatment failure, as the need for procedural termination, progression to procedural sedation, or the requirement of additional medications for anxiolysis. RESULTS: Sixty-two patients received IN dexmedetomidine {median dose [interquartile range (IQR)] of 3.05 [2.04-4.00] µg/kg/dose} compared with 58 who received oral midazolam [median (IQR) dose of 0.29 (0.25-0.48) mg/kg/dose). Providers reported high comfort and satisfaction scores, with median (IQR) scores of 90 (75-100) and 88 (60-100) of 100. Twenty-nine percent of patients experienced treatment failure, most commonly because of the need for additional medications. Those who received IN dexmedetomidine had a longer ED length of stay (6.0 vs 4.4 hours, P = 0.010). Among the patients with ASD, those who received IN dexmedetomidine had a lower rate of treatment failure compared with oral midazolam (21.2% vs 66.7%, P = 0.039). CONCLUSIONS: This study demonstrates that IN dexmedetomidine has high levels of provider comfort and satisfaction, moderately high success rate, and a promising safety profile. In addition, IN dexmedetomidine may be superior to oral midazolam in patients with ASD for anxiolysis, but additional studies are needed.

Transcriptomic analysis of equine chorioallantois reveals immune networks and molecular mechanisms involved in nocardioform placentitis.

Nocardioform placentitis (NP) continues to result in episodic outbreaks of abortion and preterm birth in mares and remains a poorly understood disease. The objective of this study was to characterize the transcriptome of the chorioallantois (CA) of mares with NP. The CA were collected from mares with confirmed NP based upon histopathology, microbiological culture and PCR for Amycolatopsis spp. Samples were collected from the margin of the NP lesion (NPL, n = 4) and grossly normal region (NPN, n = 4). Additionally, CA samples were collected from normal postpartum mares (Control; CRL, n = 4). Transcriptome analysis identified 2892 differentially expressed genes (DEGs) in NPL vs. CRL and 2450 DEGs in NPL vs. NPN. Functional genomics analysis elucidated that inflammatory signaling, toll-like receptor signaling, inflammasome activation, chemotaxis, and apoptosis pathways are involved in NP. The increased leukocytic infiltration in NPL was associated with the upregulation of matrix metalloproteinase (MMP1, MMP3, and MMP8) and apoptosis-related genes, such as caspases (CASP3 and CASP7), which could explain placental separation associated with NP. Also, NP was associated with downregulation of several placenta-regulatory genes (ABCG2, GCM1, EPAS1, and NR3C1), angiogenesis-related genes (VEGFA, FLT1, KDR, and ANGPT2), and glucose transporter coding genes (GLUT1, GLUT10, and GLUT12), as well as upregulation of hypoxia-related genes (HIF1A and EGLN3), which could elucidate placental insufficiency accompanying NP. In conclusion, our findings revealed for the first time, the key regulators and mechanisms underlying placental inflammation, separation, and insufficiency during NP, which might lead to the development of efficacious therapies or diagnostic aids by targeting the key molecular pathways.

Occurrence of potentially zoonotic and cephalosporin resistant enteric bacteria among shelter dogs in the Central and South-Central Appalachia.

BACKGROUND: Antimicrobial resistance and presence of zoonotic enteropathogens in shelter dogs pose a public health risk to shelter workers and potential adopters alike. In this study we investigated the prevalence of zoonotic bacterial pathogens and cephalosporin resistant (CefR) enteric bacteria in the feces of apparently healthy shelter dogs in the Cumberland Gap Region (CGR) in the US states of Kentucky, Tennessee and Virginia. RESULTS: Fecal samples of 59 dogs from 10 shelters in the CGR of Central and South-Central Appalachia were screened for the presence of Campylobacter jejuni, Clostridium perfringens, Salmonella and CefR enteric bacteria. C. jejuni, C. perfringens were detected by PCR based assays. Culture and PCR were used for Salmonella detection. Of 59 dogs, fecal samples from 14 (23.7%) and 8 (13.6%) dogs tested positive for cpa and hipO genes of C. perfringens and C. jejuni, respectively. Salmonella was not detected in any of the tested samples by PCR or culture. CefR enteric bacteria were isolated on MacConkey agar supplemented with ceftiofur followed by identification using MALDI-TOF. Fecal samples from 16 dogs (27.1%) yielded a total of 18 CefR enteric bacteria. Majority of CefR isolates (14/18, 77.8%) were E. coli followed by, one isolate each of Enterococcus hirae, Acinetobacter baumannii, Acinetobacter pittii, and Pseudomonas aeruginosa. CefR enteric bacteria were tested for resistance against 19- or 24-antibiotic panels using broth microdilution method. Seventeen (94.4%) CefR bacteria were resistant to more than one antimicrobial agent, and 14 (77.8%) displayed multidrug resistance (MDR). CONCLUSIONS: This study shows that shelter dogs within the CGR not only carry zoonotic bacterial pathogens, but also shed multidrug resistant enteric bacteria in their feces that may pose public health risks.

Use of Intranasal Ketamine in Pediatric Patients in the Emergency Department.

OBJECTIVES: Ketamine is a safe and widely used sedative and analgesic in the pediatric emergency department (ED). The use of intranasal (IN) ketamine in exchange for the administration of intravenous sedatives or analgesics for procedural sedation in pediatric patients is not commonplace. The goal of this study was to evaluate provider perceptions and patient outcomes at varying doses of IN ketamine for anxiolysis, agitation, or analgesia. METHODS: From January 2018 to May 2018, we performed a prospective survey and chart review of pediatric patients receiving IN ketamine. The primary outcome was to determine provider satisfaction with using IN ketamine. Secondary objectives included comparing outcomes stratified by dose, adverse events, assessing for treatment failure, and ED length of stay (LOS). As a secondary comparison, patients receiving IN ketamine whom otherwise would have required procedural sedation with intravenous sedatives or analgesics were placed into a subgroup. This subgroup of patients was compared with a cohort who received intravenous sedatives or analgesics for procedural sedation during a similar period the preceding year (January 2017 to June 2017). RESULTS: Of the 196 cases, 100% of the providers were comfortable using IN ketamine. The median overall provider satisfaction was 90 out of 100, the perception of patient comfort was 75 out of 100, and perceived patient comfort was maximized when using doses between 3 and 5 mg/kg. There were 15 (7.7%) patients who experienced ketamine treatment failure. Overall, the rate of adverse events was 6%, but were considered minor [nausea (n = 3; 1.5%), dizziness (n = 2; 1%), and drowsiness (n = 2; 1%)]. No patients required respiratory support or intubation. The mean LOS was 237.9 minutes, compared with those who underwent procedural sedation with an LOS of 332.4 minutes (P < 0.001). CONCLUSIONS: This study demonstrates that IN ketamine was able to provide safe and successful analgesia and anxiolysis in pediatric patients in an ED setting. In addition, providers expressed a high degree of satisfaction with using IN ketamine (90 out of 100) in addition to a high degree of patient comfort during the procedure (75 out of 100). Intranasal ketamine provides an alternative to intravenous medication normally requiring more resource-intensive monitoring. Procedural sedations are resource and time intensive activities that increase ED LOS. Intranasal ketamine used for anxiolysis and analgesia offers the benefits of freeing up resources of staff and monitoring while enhancing overall throughput through a pediatric ED.

Emergence of Resistance to Macrolides and Rifampin in Clinical Isolates of Rhodococcus equi from Foals in Central Kentucky, 1995 to 2017.

The objective of this study was to determine the prevalence of Rhodococcus equi strains resistant to macrolides and rifampin over time in clinical samples from foals submitted to diagnostic laboratories in central Kentucky. We performed a retrospective observational study of all clinical samples from foals that were submitted to veterinary diagnostic laboratories in Kentucky between January 1995 and December 2017. Samples were included if the R. equi bacterium was cultured and tested for in vitro susceptibility to erythromycin or rifampin. In vitro susceptibility testing to erythromycin was available for 2,169 isolates of R. equi, while susceptibility testing to both erythromycin and rifampin was available for 1,681 isolates. Rifampin resistance was first detected in 2000, and erythromycin resistance was first detected in 2004. Between 1995 and 2006, the proportion of resistant isolates of R. equi was 0.7% for erythromycin and 2.3% for rifampin. There was a significant (P < 0.001) increase in the proportion of resistant R. equi between 2007 and 2017, with 13.6% of isolates being resistant to erythromycin and 16.1% being resistant to rifampin. Between 2007 and 2017, isolates of R. equi resistant to erythromycin or rifampin were significantly less likely to be isolated from feces than from the respiratory tract, other soft tissues, or musculoskeletal infections. The considerable increase in the prevalence of isolates of R. equi resistant to macrolides and rifampin since 2007 is of concern for both human and animal health.

An epidemiologic study of antimicrobial resistance of Staphylococcus species isolated from equine samples submitted to a diagnostic laboratory.

BACKGROUND: Antimicrobial resistance limits traditional treatment options and increases costs. It is therefore important to estimate the magnitude of the problem so as to provide empirical data to guide control efforts. The aim of this study was to investigate the burden and patterns of antimicrobial resistance (AMR) among equine Staphylococcus samples submitted to the University of Kentucky Veterinary Diagnostic Laboratory (UKVDL) from 1993 to 2009. Retrospective data of 1711 equine Staphylococcus samples submitted to the UKVDL during the time period 1993 to 2009 were included in the study. Antimicrobial susceptibility testing, that included 16 drugs, were performed using cultures followed by the Kirby-Bauer disk diffusion susceptibility test. The proportion of resistant isolates by animal breed, species of organism, sample source, and time period were computed. Chi-square and Cochran-Armitage trend tests were used to identify significant associations and temporal trends, respectively. Logistic regression models were used to investigate predictors of AMR and multidrug resistance (MDR). RESULTS: A total of 66.3% of the isolates were resistant to at least one antimicrobial, most of which were Staphylococcus aureus (77.1%), while 25.0% were MDR. The highest level of resistance was to penicillins (52.9%). Among drug classes, isolates had the highest rate of AMR to at least one type of ß-lactams (49.2%), followed by aminoglycosides (30.2%). Significant (p < 0.05) associations were observed between odds of AMR and horse breed, species of organism and year. Similarly, significant (p < 0.05) associations were identified between odds of MDR and breed and age. While some isolates had resistance to up to 12 antimicrobials, AMR profiles featuring single antimicrobials such as penicillin were more common than those with multiple antimicrobials. CONCLUSION: Demographic factors were significant predictors of AMR and MDR. The fact that some isolates had resistance to up to 12 of the 16 antimicrobials assessed is quite concerning. To address the high levels of AMR and MDR observed in this study, future studies will need to focus on antimicrobial prescription practices and education of both practitioners and animal owners on judicious use of antimicrobials to slow down the development of resistance.

In vitro culture of Parascaris equorum larvae and initial investigation of parasite excretory-secretory products.

Currently, diagnosis of Parascaris equorum infection in equids is limited to patent infections. The goals of this study were to culture P. equorum larvae in vitro and identify excretory-secretory (ES) products for prepatent diagnostic testing. Parascaris equorum L2/L3 larvae were hatched and cultured for up to 3 weeks for ES product collection. Fifth stage (L5) P. equorum were also cultured for ES product collection. Examination of ES fractions by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and silver stain revealed L2/L3 products ranging from 12-94 kDa and L5 products ranging from 12-189 kDa. Western blot analyses were conducted using polyclonal antibodies produced against P. equorum or Baylisascaris procyonis L2/L3 ES products, sera from rabbits inoculated with B. procyonis or Toxocara canis eggs, and sera from animals naturally infected with P. equorum or T. canis. Western blot results indicated parasite antigens migrating at 19 and 34 kDa may be useful for specifically detecting P. equorum infections.

Management of pediatric type III supracondylar humerus fractures in the United States: results of a national survey of pediatric orthopaedic surgeons.

BACKGROUND: Supracondylar humerus fractures are common injuries in the pediatric population. The most severe, type III injuries, have seen the most debate on treatment regimens. Traditionally, these fractures were treated as surgical emergencies, most often fixed with percutaneous pinning in a cross-pin configuration. The recent literature shows that delayed fixation is comparable to emergent fixation as long as there is no vascular compromise with the injury. METHODS: A short survey was sent to Pediatric Orthopaedic Society of North America (POSNA) members using an online survey and questionnaire service. The purpose of the survey was to establish an overview of current practices in the United States concerning treatment of type III supracondylar humerus fractures and the influence of the recent literature on the management of these injuries. RESULTS: A total of 309 members, representing a wide range of locations and years in practice, responded to our survey. About 81% preferred to splint type III supracondylar humerus fractures and plan for fixation the following morning, assuming there was no issue necessitating emergent fixation. The preferred method of percutaneous fixation was fairly evenly distributed between cross-pin configuration (30%), 2 lateral pins (33%), and 3 lateral pins (37%). About 56% of those surveyed stated that the recent literature showing comparable outcomes with 2 lateral pins versus a cross-pin configuration had not changed their approaches to management of these fractures concerning the method of fixation. CONCLUSIONS: The trend in management of type III supracondylar humerus fractures in children is progressing toward delayed treatment and lateral pin configuration. The results provide an overview of the current practice of POSNA members concerning management of these fractures. We believe this information is beneficial to both pediatric-trained and nonpediatric-trained orthopaedic surgeons to help guide their decisions when dealing with these injuries. LEVEL OF EVIDENCE: This study is a Level V Therapeutic Study reviewing trends in the management of type III supracondylar humerus fractures in children. The previously described experts represent various levels of expertise in their preferred method of fixation.

Antimicrobial resistance among Streptococcus equi subspecies zooepidemicus and Rhodococcus equi isolated from equine specimens submitted to a diagnostic laboratory in Kentucky, USA.

Background: Surveillance of antimicrobial resistance (AMR) among veterinary pathogens is necessary to identify clinically relevant patterns of AMR and to inform antimicrobial use practices. Streptococcus equi subsp. zooepidemicus and Rhodococcus equi are bacterial pathogens of major clinical importance in horses and are frequently implicated in respiratory tract infections. The objectives of this study were to describe antimicrobial resistance patterns and identify predictors of AMR and multidrug resistance (MDR) (resistance to three or more antimicrobial classes) among equine S. zooepidemicus and R. equi isolates. Methods: Antimicrobial susceptibility data from equine specimens submitted to the University of Kentucky Veterinary Diagnostic Laboratory between 2012 and 2017 were used in the study. Temporal trends in AMR and MDR were assessed using the Cochran-Armitage test. Logistic regression was used to identify associations between patient characteristics and the following outcomes: (a) MDR among S. zooepidemicus isolates, and (b) resistance to macrolides and ansamycins (rifampin) among R. equi isolates. Logistic regression was also used to investigate whether resistance of S. zooepidemicus and R. equi isolates to an antimicrobial class could be predicted by resistance to other drug classes. Results: The vast majority of S. zooepidemicus (99.6%) and R. equi isolates (83%) were resistant to at least one antimicrobial agent, but no significant temporal trends in AMR were observed. Approximately half (53.3%) of the S. zooepidemicus isolates were multidrug-resistant, and there was a significant (p < 0.001) increasing temporal trend of MDR among S. zooepidemicus isolates. Resistance to penicillin, which is typically recommended for treatment of suspected S. zooepidemicus infections, also increased during the study period, from 3.3% to 9.5%. Among R. equi isolates, 19.2% were resistant to one or more macrolide antibiotics, 24% were resistant to rifampin, and 15.6% were resistant to both macrolide(s) and rifampin. For both organisms, resistance to an antimicrobial class could be predicted based on resistance profiles to other drug classes. For instance, significant (p < 0.01) predictors of ß-lactam resistance among S. zooepidemicus isolates included resistance to macrolides (Odds Ratio (OR) = 14.7) and ansamycins (OR = 9.3). Resistance to phenicols (OR = 3.7) and ansamycins (OR = 19.9) were associated with higher odds of macrolide resistance among R. equi isolates. Conclusions: The increase in MDR among S. zooepidemicus isolates is concerning. The observed levels of resistance to macrolides and rifampin among R. equi are also worrisome given the limited number of antimicrobials available for treatment of this organism. The findings of this study highlight the importance of ongoing surveillance of AMR to guide treatment decisions and directions for future research.

GaAs nanowires on Si nanopillars: towards large scale, phase-engineered arrays.

Large-scale patterning for vapor-liquid-solid growth of III-V nanowires is a challenge given the required feature size for patterning (45 to 60 nm holes). In fact, arrays are traditionally manufactured using electron-beam lithography,for which processing times increase greatly when expanding the exposure area. In order to bring nanowire arrays one step closer to the wafer-scale we take a different approach and replace patterned nanoscale holes with Si nanopillar arrays. The method is compatible with photolithography methods such as phase-shift lithography or deep ultraviolet (DUV) stepper lithography. We provide clear evidence on the advantage of using nanopillars as opposed to nanoscale holes both for the control on the growth mechanisms and for the scalability. We identify the engineering of the contact angle as the key parameter to optimize the yield. In particular, we demonstrate how nanopillar oxidation is key to stabilize the Ga catalyst droplet and engineer the contact angle. We demonstrate how the position of the triple phase line at the SiO2/Si as opposed to the SiO2/vacuum interface is central for a successful growth. We compare our experiments with simulations performed in surface evolver™ and observe a strong correlation. Large-scale arrays using phase-shift lithography result in a maximum local vertical yield of 67% and a global chip-scale yield of 40%. We believe that, through a greater control over key processing steps typically achieved in a semiconductor fab it is possible to push this yield to 90+% and open perspectives for deterministic nanowire phase engineering at the wafer-scale.

Effects of location for collection of air samples on a farm and time of day of sample collection on airborne concentrations of virulent Rhodococcus equi at two horse breeding farms.

OBJECTIVE: To determine whether airborne concentrations of virulent Rhodococcus equi at 2 horse breeding farms varied on the basis of location, time of day, and month. SAMPLE POPULATION: 2 farms in central Kentucky with recurrent R equi-induced pneumonia in foals. PROCEDURES: From February through July 2008, air samples were collected hourly for a 24-hour period each month from stalls and paddocks used to house mares and their foals. Concentrations of airborne virulent R equi were determined via a modified colony immunoblot technique. Differences were compared by use of zero-inflated negative binomial methods to determine effects of location, time, and month. RESULTS: Whether mares and foals were housed predominantly in stalls or paddocks significantly affected results for location of sample collection (stall vs paddock) by increasing airborne concentrations of virulent R equi at the site where horses were predominantly housed. Airborne concentrations of virulent R equi were significantly higher from 6:00 pm through 11:59 pm than for the period from midnight through 5:59 am. Airborne concentrations of virulent R equi did not differ significantly between farms or among months. CONCLUSIONS AND CLINICAL RELEVANCE: Airborne concentrations of virulent R equi were significantly increased when horses were predominantly housed at the site for collection of air samples (ie, higher in stalls when horses were predominantly housed in stalls and higher in paddocks when horses were predominantly housed in paddocks). Concentrations of virulent R equi among air samples collected between the hours of 6:00 am and midnight appeared similar.

A proposal to leverage high-quality veterinary diagnostic laboratory large data streams for animal health, public health, and One Health.

Test data generated by ~60 accredited member laboratories of the American Association of Veterinary Laboratory Diagnosticians (AAVLD) is of exceptional quality. These data are captured by 1 of 13 laboratory information management systems (LIMSs) developed specifically for veterinary diagnostic laboratories (VDLs). Beginning ~2000, the National Animal Health Laboratory Network (NAHLN) developed an electronic messaging system for LIMS to automatically send standardized data streams for 14 select agents to a national repository. This messaging enables the U.S. Department of Agriculture to track and respond to high-consequence animal disease outbreaks such as highly pathogenic avian influenza. Because of the lack of standardized data collection in the LIMSs used at VDLs, there is, to date, no means of summarizing VDL large data streams for multi-state and national animal health studies or for providing near-real-time tracking for hundreds of other important animal diseases in the United States that are detected routinely by VDLs. Further, VDLs are the only state and federal resources that can provide early detection and identification of endemic and emerging zoonotic diseases. Zoonotic diseases are estimated to be responsible for 2.5 billion cases of human illness and 2.7 million deaths worldwide every year. The economic and health impact of the SARS-CoV-2 pandemic is self-evident. We review here the history and progress of data management in VDLs and discuss ways of seizing unexplored opportunities to advance data leveraging to better serve animal health, public health, and One Health.

Antibiotic prescription practices and opinions regarding antimicrobial resistance among veterinarians in Kentucky, USA.

BACKGROUND: Inappropriate antimicrobial use (AMU) is a global concern. Opinions of veterinarians regarding AMU and its role in the development of antimicrobial resistance (AMR) may influence their prescription practices. It is important to understand these opinions, prescription practices and their potential impact on the development of AMR in order to guide efforts to curb the problem. Therefore, the objective of this study was to investigate the antimicrobial prescription practices and opinions of veterinarians in Kentucky regarding AMU and AMR. METHODS: This cross-sectional study used a 30-question survey questionnaire administered to veterinarians who were members of the Kentucky Veterinary Medical Association. Survey responses from 101 participants were included in the study. Descriptive statistics were computed and associations between categorical variables assessed using Chi-square or Fisher's exact tests. Firth logistic models were used to investigate predictors of "Compliance with prescription policies" and "Cost of antimicrobial affects prescription decisions". RESULTS: Almost all (93%) respondents indicated that improper AMU contributed to selection for AMR. A total of 52% of the respondents believed that antimicrobials were appropriately prescribed, while the remaining 48% believed that antimicrobials were inappropriately prescribed. Significant predictors of compliance with prescription policies were availability of prescription policy at the veterinary facility (Odds Ratio (OR) = 4.2; p<0.001) and over-prescription (OR = 0.35; p = 0.025). Similarly, significant predictors of cost of antimicrobials affecting prescription decisions were lack of post-graduate training (OR = 8.3; p = 0.008) and practice type, with large animal practices having significantly lower odds of the outcome (OR = 0.09; p = 0.004) than small animal practices. CONCLUSION: Most veterinarians indicated that improper AMU contributed to selection for AMR. Since the odds of compliance with prescription policies were 4-times higher among veterinarians working at facilities that had prescription policies compared to those at facilities that didn't, more veterinary facilities should be encouraged to adopt prescription policies to help improve compliance and reduce AMR. Veterinarians would also benefit from continued professional education to help improve prescription practices, antimicrobial stewardship and curb AMR.

Serological Survey of Leptospira Infection in Arabian Horses in Poland.

Leptospirosis is one of the most common zoonotic infections worldwide, including in most livestock, some companion animals, horses, wildlife, and humans. Epidemiological estimation of its prevalence in all species is difficult due to the variety of clinical presentations and challenges regarding laboratory diagnosis. The purpose of this study was to measure the seroprevalence of leptospiral infection in Arabian horses kept in the largest breeding farms in Poland, representing over 15% of the Polish Arabian horse population. Leptospira antibodies were detected by MAT (cut-off 1:100) in 33.2% of serum samples (204 of 615 animals) (CI 95%: 29.6-37.0%), most frequently reacting with the serovar Grippotyphosa, similar to previous reports in populations of randomly selected horses. These results indicated high Leptospira seropositivity, thus, although any form of clinical leptospirosis is rare, it may be postulated that the leptospiral exposure is widespread.

Identification of a Ruminant Origin Group B Rotavirus Associated with Diarrhea Outbreaks in Foals.

Equine rotavirus group A (ERVA) is one of the most common causes of foal diarrhea. Starting in February 2021, there was an increase in the frequency of severe watery to hemorrhagic diarrhea cases in neonatal foals in Central Kentucky. Diagnostic investigation of fecal samples failed to detect evidence of diarrhea-causing pathogens including ERVA. Based on Illumina-based metagenomic sequencing, we identified a novel equine rotavirus group B (ERVB) in fecal specimens from the affected foals in the absence of any other known enteric pathogens. Interestingly, the protein sequence of all 11 segments had greater than 96% identity with group B rotaviruses previously found in ruminants. Furthermore, phylogenetic analysis demonstrated clustering of the ERVB with group B rotaviruses of caprine and bovine strains from the USA. Subsequent analysis of 33 foal diarrheic samples by RT-qPCR identified 23 rotavirus B-positive cases (69.69%). These observations suggest that the ERVB originated from ruminants and was associated with outbreaks of neonatal foal diarrhea in the 2021 foaling season in Kentucky. Emergence of the ruminant-like group B rotavirus in foals clearly warrants further investigation due to the significant impact of the disease in neonatal foals and its economic impact on the equine industry.

Antimicrobial susceptibility patterns of Rhodococcus equi from necropsied foals with rhodococcosis.

Mainstay therapy for rhodococcosis in foals is the combination of rifampicin and a macrolide. While emergence of resistance to rifampicin and macrolides has been reported, studies demonstrating the development of resistance to such drugs is limited in necropsied foals with rhodococcosis. In this study, the foal necropsy records between 01/01/2011 and 08/30/2019 were reviewed for culture-positive R. equi with MICs and, whether or not the affected foals received any mainstay dual therapy before their deaths. Resistance to antimicrobials in the R. equi isolates from necropsied foals were then compared between treated foals with dual therapy and untreated foals to determine the association between the administration of antimicrobials and development of the drug resistance. In a total of 256 R. equi isolates from each of the 256 necropsied foals with rhodococcosis, rifampicin, azithromycin, clarithromycin and erythromycin showed high rates of resistance, 22.65 %, 16.01 %, 14.84 % and 15.23 %, respectively. The most active antimicrobials exhibiting MIC50/90 values were imipenem, doxycycline, amikacin and gentamicin including in the rifampicin- and macrolides-resistant R. equi isolates. Based on the treatment histories available for the 114 necropsied foals with rhodococcosis, R. equi isolates resistant to rifampicin, and macrolides were significantly more isolated from treated foals with mainstay dual therapy compared to untreated foals. Despite dual therapy, development of resistance against rifampicin and macrolides warrants evaluation of new treatment protocols in foals.

Application of an automated surveillance-data-analysis system in a laboratory-based early-warning system for detection of an abortion outbreak in mares.

OBJECTIVE: To develop an early-warning automated surveillance-data-analysis system for early outbreak detection and reporting and to assess its performance on an abortion outbreak in mares in Kentucky. SAMPLE POPULATION: 426 data sets of abortions in mares in Kentucky during December 2000 to July 2001. PROCEDURES: A custom software system was developed to automatically extract and analyze data from a Laboratory Information Management System database. The software system was tested on data on abortions in mares in Kentucky reported between December 1, 2000, and July 31, 2001. The prospective space-time permutations scan statistic, proposed by Kulldorff, was used to detect and identify abortion outbreak signals. RESULTS: Results indicated that use of the system would have detected the abortion outbreak approximately 1 week earlier than traditional surveillance systems. However, the geographic scale of analysis was critical for highest sensitivity in outbreak detection. Use of the lower geographic scale of analysis (ie, postal [zip code]) enhanced earlier detection of significant clusters, compared with use of the higher geographic scale (ie, county). CONCLUSIONS AND CLINICAL RELEVANCE: The automated surveillance-data-analysis system would be useful in early detection of endemic, emerging, and foreign animal disease outbreaks and might help in detection of a bioterrorist attack. Manual analyses of such a large number of data sets (ie, 426) with a computationally intensive algorithm would be impractical toward the goal of achieving near real-time surveillance. Use of this early-warning system would facilitate early interventions that should result in more positive health outcomes.

Association of soil concentrations of Rhodococcus equi and incidence of pneumonia attributable to Rhodococcus equi in foals on farms in central Kentucky.

OBJECTIVE: To determine whether soil concentrations of total or virulent Rhodococcus equi differed among breeding farms with and without foals with pneumonia caused by R equi. SAMPLE POPULATION: 37 farms in central Kentucky. Procedures-During January, March, and July 2006, the total concentration of R equi and concentration of virulent R equi were determined by use of quantitative bacteriologic culture and a colony immunoblot technique, respectively, in soil specimens obtained from farms. Differences in concentrations and proportion of virulent isolates within and among time points were compared among farms. RESULTS: Soil concentrations of total or virulent R equi did not vary among farms at any time point. Virulent R equi were identified in soil samples from all farms. Greater density of mares and foals was significantly associated with farms having foals with pneumonia attributable to R equi. Among farms with affected foals, there was a significant association of increased incidence of pneumonia attributable to R equi with an increase in the proportion of virulent bacteria between samples collected in March and July. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that virulent R equi were commonly recovered from soil of horse breeding farms in central Kentucky, regardless of the status of foals with pneumonia attributable to R equi on each farm. The incidence of foals with pneumonia attributable to R equi can be expected to be higher at farms with a greater density of mares and foals.

Pulling together: interagency coordination and HIV/STD prevention.

Using multiple network comparisons, we determined whether sexually transmitted disease (STD) rates or black-white STD rate differences are related to how HIV prevention agencies interact through exchanges of information, clients, or funds. In 10 North Carolinian counties, we conducted a cross-sectional analysis, using each county's network as the unit of interest. Using data from face-to-face interviews, measures of the density (overall connectedness) and degree centralization (amount of centralized information hubs) were calculated with UCINET. Statistical significance of the associations between county characteristics and STD rates was assessed with exact Wilcoxon rank sum test. Syphilis rates were lower (P = .01) in counties with a high network density, on the basis of exchanges of information or clients. The effect on black-white rate differences was in the same direction but weaker. Where network degree centralization was high, syphilis rates were higher and the black-white rate differences were larger. Gonorrhea rates demonstrated similar but attenuated patterns of association with network characteristics. STD prevention is more effective when all agencies interact with each other (density) but less effective when interactions are predominantly with a few central agencies (degree centralization). The measures of network exchanges employed in this study may be appropriate for future assessment of service provision of funded prevention programs.