Investigation of the seroprevalence to equine coronavirus and SARS-CoV-2 in healthy adult horses recently imported to the United States.

Adult horses are susceptible to equine coronavirus (ECoV) and severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), although, only ECoV has been linked to clinical disease. Little information is available regarding the seroprevalence against ECoV and SARS-CoV-2 in adult healthy horses. The goal of the present study was to determine the seroprevalence against two coronaviruses known to infect horses using convenience samples collected from horses recently imported from Europe to the United States from 2019 to 2023. A total of 385 banked serum samples were tested against ECoV and SARS-CoV-2 using previously validated ELISA assays. Prevalence factors including date of arrival in the United States, signalment and country of origin were available for the majority of the horses. A total of 9/385 (2.3%) and 4/385 (1.0%) horses tested seropositive for ECoV and SARS-CoV-2, respectively. The ECoV seropositive horses were all mares, ages 4 to 26 years (median 9 years) and originated from Germany, the Netherlands, Ireland, Belgium and Italy. These mares were predominantly imported during the summer and fall months. All SARS-CoV-2 seropositive horses were mares ages 5 to 10 years (median 7.5 years) imported from the Netherlands and the United Kingdom. The majority of the SARS-CoV-2 seropositive horses were imported during the colder months of the year. The study results support the presence of ECoV in Europe and report on the first SARS-CoV-2 seropositive healthy adult horses outside the United States. Commingling for movements by air and close contact to humans may predispose transmission with ECoV and SARS-CoV-2, respectively.

Comparison of antibody and antigen response to intranasal and intramuscular EHV-1 modified-live vaccination in healthy adult horses.

During neurological EHV-1 outbreaks, modified-live vaccines (MLV) are often administrated intranasally in an off-label fashion to healthy cohort horses in order to achieve rapid mucosal immunity. Thus, the goal of the present study was to determine if a commercially available EHV-1 MLV given intranasally to healthy horses would trigger a measurable systemic and/or mucosal antibody response. Eight healthy adult horses were given the EHV-1 MLV vaccine intranasally, while 8 healthy adult horses received the vaccine intramuscularly. An additional 8 healthy horses served as unvaccinated controls. EHV-1 specific antibodies (total IgG, IgG4/7, IgG1 and IgA) were measured in blood and nasal secretions prior to vaccine administration and 14- and 30-days post-vaccine administration. Further, nasal secretions and whole blood were tested for the presence of EHV-1 DNA by qPCR prior to and 5 days after vaccine administration. EHV-1 was detected by qPCR for the first 48 hours post-intranasal vaccine administration in nasal secretions in a total of three horses. Total EHV-1 IgG and IgG4/7 antibody values in serum increased only in horses receiving the intramuscular MLV. Antibody values at 14- and 30-days post vaccine administration were not different from values prior to vaccine administration in horses receiving the intranasal vaccine. The results support the intramuscular use of the EHV-1 MLV as recommended by the manufacturer. Intranasal vaccination with the study-specific EHV-1 MLV did not induce an increase in systemic or nasal antibodies, therefore, this vaccine route seems suboptimal and should not be used to vaccinate adult horses that have received multiple EHV-1 vaccinations and have pre-existing antibodies against EHV-1.

Characterization of Equine Rhinitis B Virus Infection in Clinically Ill Horses in the United States during the Period 2012-2023.

Equine rhinitis B virus is a lesser-known equine respiratory pathogen that is being detected with increasing frequency via a voluntary upper respiratory biosurveillance program in the United States. This program received 8684 nasal swab submissions during the years 2012-2023. The nasal swabs were submitted for qPCR testing for six common upper respiratory pathogens: Streptococcus equi subspecies equi (S. equi), equine influenza virus (EIV), equine herpesvirus type 1 (EHV-1), equine herpesvirus type 4 (EHV-4), equine rhinitis A virus (ERAV), and equine rhinitis B virus (ERBV). The overall ERBV qPCR-positivity rate was 5.08% (441/8684). ERBV was detected as a single pathogen in 291 cases (65.99% of positives, 291/441) and was detected as a coinfection with at least one other respiratory pathogen in 150 cases (34.01%, 150/441). Young horses, less than a year of age, with acute onset of fever and respiratory signs and horses used for competition are more likely to test qPCR-positive for ERBV. Horses with ERBV may present with fever, nasal discharge, ocular discharge, and/or cough. Coinfection is a common feature of ERBV infection and S. equi, EHV-4 and EIV were the most common pathogens coinfected with ERBV. This report provides important information regarding the clinical relevance of ERBV in the horse and begins investigating the impact of coinfection on clinical disease.

Detection of Selected Equine Respiratory Pathogens in Stall Samples Collected at a Multi-Week Equestrian Show during the Winter Months.

The aim of this study was to use environmental sampling to determine the frequency of detection of selected equine respiratory viruses and bacteria in horses attending a multi-week equestrian show during the winter months. At four time points during showing, environmental sponge samples were collected from all stalls on the property and tested for the presence of equine herpesvirus-1 (EHV-1), EHV-2, EHV-4, equine influenza virus (EIV), equine rhinitis B virus (ERBV), Streptococcus equi ss. equi (S. equi), and S. equi ss. zooepidemicus (S. zooepidemicus) using real-time PCR (PCR). Environmental sponges were collected from all 53 barns by using one sponge for up to 10 stalls. Further, 2/53 barns were randomly selected for individual stall sampling in order to compare the results between individual and pooled stall samples. A total of 333/948 (35.13%, 95% CI 32.09-38.26%) pooled environmental stall sponges tested PCR-positive for at least one of the selected respiratory pathogens. Streptococcus zooepidemicus was the most commonly detected pathogen in pooled samples (28.69%, 95% CI 25.83-31.69%), followed by EHV-2 (14.45%, 95% CI 12.27-16.85%), EHV-4 (1.37%, 95% CI 0.73-2.33%), and a very small percentage of pooled stall sponges tested PCR-positive for EHV-1, ERBV, EIV, and S. equi. In individual samples, 171/464 (36.85%, 95% CI 32.45-41.42%) environmental stall sponges tested PCR-positive for at least one of the selected pathogens, following a similar frequency of pathogen detection as pooled samples. The detection frequency of true respiratory pathogens from environmental samples was higher during the winter months compared to previous studies performed during spring and summer, and this testing highlights that such pathogens circulate with greater frequency during the colder months of the year. The strategy of monitoring environmental stall samples for respiratory pathogens circumvents the often labor-intensive collection of respiratory secretions from healthy horses and allows for a more efficient assessment of pathogen buildup over time. However, environmental stall testing for respiratory pathogens should not replace proper biosecurity protocols, but it should instead be considered as an additional tool to monitor the silent circulation of respiratory pathogens in at-risk horses.

Investigation of the Frequency of Detection of Common Respiratory Pathogens in Nasal Secretions and Environment of Healthy Sport Horses Attending a Multi-Week Show Event during the Summer Months.

Little information is presently available regarding the frequency of the silent shedders of respiratory viruses in healthy sport horses and their impact on environmental contamination. Therefore, the aim of this study was to investigate the detection frequency of selected respiratory pathogens in nasal secretions and environmental stall samples of sport horses attending a multi-week equestrian event during the summer months. Six out of fifteen tents were randomly selected for the study with approximately 20 horse/stall pairs being sampled on a weekly basis. Following weekly collection for a total of 11 weeks, all samples were tested for the presence of common respiratory pathogens (EIV, EHV-1, EHV-4, ERAV, ERBV, and Streptococcus equi ss equi (S. equi)) using qPCR. A total of 19/682 nasal swabs (2.8%) and 28/1288 environmental stall sponges (2.2%) tested qPCR-positive for common respiratory pathogens. ERBV was the most common respiratory virus (17 nasal swabs, 28 stall sponges) detected, followed by EHV-4 (1 nasal swab) and S. equi (1 nasal swab). EIV, EHV-1, EHV-4 and ERAV were not detected in any of the study horses or stalls. Only one horse and one stall tested qPCR-positive for ERBV on two consecutive weeks. All the other qPCR-positive sample results were related to individual time points. Furthermore, only one horse/stall pair tested qPCR-positive for ERBV at a single time point. The study results showed that in a selected population of sport horses attending a multi-week equestrian event in the summer, the frequency of the shedding of respiratory viruses was low and primarily restricted to ERBV with little evidence of active transmission and environmental contamination.

Multi-Centered Field Evaluation of a Salmonella spp. Point-of-Care PCR Assay Using Equine Feces and Environmental Samples.

The introduction of microfluidic card technology has opened the field for rapid point-of-care (POC) molecular assays, including fecal and environmental Salmonella spp. testing. The purpose of this study was to evaluate a novel POC PCR assay for the detection of Salmonella spp. in feces and environmental samples. A total of 143 fecal samples and 132 environmental samples were collected for POC PCR Salmonella spp. testing as well as qPCR testing. Each sample was inoculated into selenite broth and incubated for 18 to 24 hours. For the POC PCR assay, 14 µl of selenite broth were mixed with 126 µl of PCR reaction mix and pipetted into a microfluidic test card targeting the invA and ttrC gene of Salmonella enterica. For qPCR analysis, 200 µl of the selenite broth were processed for DNA purification and Salmonella spp. testing targeting the invA gene. The overall agreement between the POC PCR Salmonella spp. assay and qPCR assay was 88.1% for feces and 97.0% for environmental samples. Strong agreement and short turn-around-time make the POC device the first molecular diagnostic platform allowing detection of Salmonella spp. in a hospital setting without having to ship out samples to a veterinary diagnostic laboratory. The availability of an accurate POC PCR assay for the detection of Salmonella spp. will enhance the diagnostic capability of equine veterinarians to timely support a diagnosis of salmonellosis and also monitor the environment in order to reduce the risk of nosocomial infections.

Voluntary Surveillance Program for Equine Influenza Virus in the United States during 2008-2021.

A voluntary upper respiratory biosurveillance program in the USA received 9740 nasal swab submissions during the years 2008-2021 from 333 veterinarians and veterinary clinics. The nasal swabs were submitted for qPCR testing for six common upper respiratory pathogens:equine influenza virus (EIV), equine herpesvirus-1 (EHV-1), equine herpesvirus-4 (EHV-4), Streptococcus equi subspecies equi (S. equi), equine rhinitis A virus (ERAV), and equine rhinitis B virus (ERBV). Additional testing was performed for equine gamma herpesvirus-2 (EHV-2) and equine gamma herpesvirus-5 (EHV-5) and the results are reported. Basic frequency statistics and multivariate logistic regression models were utilized to determine the associations between risk factors and EIV positivity. The EIV qPCR-positivity rate was 9.9%. Equids less than 9 years of age with a recent history of travel and seasonal occurrence in winter and spring were the most common population that were qPCR positive for EIV. This ongoing biosurveillance program emphasizes the need for molecular testing for pathogen identification, which is critical for decisions associated with therapeutics and biosecurity intervention for health management and vaccine evaluations and development.

Voluntary Biosurveillance of Streptococcus equi Subsp. equi in Nasal Secretions of 9409 Equids with Upper Airway Infection in the USA.

This study aimed to describe selected epidemiological aspects of horses with acute onset of fever and respiratory signs testing qPCR-positive for S. equi and to determine the effect of vaccination against S. equi on qPCR status. Horses with acute onset of fever and respiratory signs from all regions of the United States were included in a voluntary biosurveillance program from 2008 to 2020 and nasal secretions were tested via qPCR for S. equi and common respiratory viruses. A total of 715/9409 equids (7.6%) tested qPCR-positive for S. equi, with 226 horses showing coinfections with EIV, EHV-1, EHV-4, and ERBV. The median age for the S. equi qPCR-positive horses was 8 ± 4 years and there was significant difference when compared to the median age of the S. equi qPCR-negative horses (6 ± 2 years; p = 0.004). Quarter Horse, Warmblood, and Thoroughbred were the more frequent breed in this horse population, and these breeds were more likely to test qPCR-positive for S. equi compared to other breeds. There was not statistical difference for sex between S. equi qPCR-positive and qPCR-negative horses. Horses used for competition and ranch/farm use were more likely to test qPCR-positive for S. equi (p = 0.006). Horses that tested S. equi qPCR-positive were more likely to display nasal discharge, fever, lethargy, anorexia, and ocular discharge compared to horses that tested S. equi qPCR-negative (p = 0.001). Vaccination against S. equi was associated with a lower frequency of S. equi qPCR-positive status.

Investigation of the EHV-1 Genotype (N752, D752, and H752) in Swabs Collected From Equids With Respiratory and Neurological Disease and Abortion From the United States (2019-2022).

Contemporary data on equine herpesvirus-1 (EHV-1) genotype (non-neuropathogenic or N752, neuropathogenic or D752 and new variant or H752) in clinically diseased equids is important in order to determine the frequency of these genotypes and their association with disease expression. A total of 297 EHV-1 qPCR-positive swabs collected from 2019 to 2022 from horses with respiratory disease (EHV-1), neurological disease (equine herpesvirus-1 myeloencephalopathy [EHM]) and abortion were tested for the three different EHV-1 genotypes (N752, D752 and H752) using qPCR allelic discrimination assays. All submissions originated from the United States and included 257 EHV-1 cases, 35 EHM cases and 5 cases of abortion. EHV-1 qPCR-positive cases were predominantly seen during winter and spring. N752 was the predominant genotype detected in EHV-1 cases (87.5%), EHM cases (74.3%) and abortions (80%). D752 was detected less frequently in EHV-1 cases (9.3%) and EHM cases (25.7%), while H752 was only detected in EHV-1 cases (3.1%). While the N752 genotype has remained the predominant genotype affecting horses with respiratory disease and abortion, it has also become a leading genotype in cases of EHM, when compared to historical data. The new H752 genotype, first reported in the United States in 2021, has remained confined to a cluster of geographically and temporally related outbreaks and the data showed no emerging spread of H752 since it was first reported. While the monitoring of EHV-1 genotypes is important from a diagnostic and epidemiological standpoint, it may also help establish medical interventions and preventive protocols to reduce the risk of severe complications associated with EHV-1 infection.

Investigation of the Systemic Antibody Response and Antigen Detection Following Intranasal Administration of Two Commercial Equine Herpesvirus-1 Vaccines to Adult Horses.

EHV-1 vaccines are often administered intranasally during emergency situation such as outbreaks of equine herpesvirus myeloencephalopathy. However, there is currently no data available on the efficacy of such protocols, nor the diagnostic challenge when recently vaccinated horses become clinically infected and nasal secretions are collected to support a diagnosis of EHV-1 infection. Therefore, the objective of this study was to determine if two commercially available EHV-1 vaccines, a killed-adjuvanted (Calvenza) and a modified-live (Rhinomune) EHV-1 vaccine, could induce a measurable systemic antibody response postintranasal administration. A second objective was to determine the detection time of EHV-1 in nasal secretions by qPCR following the intranasal administration of the respective EHV-1 vaccines. Thirty healthy adult horses, with no recent EHV-1 vaccine administration, were randomly assigned to one of three groups: Rhinomune group, Calvenza group, and unvaccinated control group. Total Ig and isotype-specific IgG4/7 against EHV-1 measured pre- and 30-days post-vaccination were not different amongst the three study groups. Vaccine-derived EHV-1 was only detected in the two EHV-1 vaccine groups with 9/10 horses in the Rhinomune group and 8/10 horses in the Calvenza group testing qPCR-positive for EHV-1 for 1 to 3 days. There was no significant difference in number of horses testing qPCR-positive for EHV-1 and absolute quantitation of EHV-1 in nasal secretions by qPCR between the two vaccine groups. The intranasal administration of two commercial EHV-1 vaccines did not elicit a systemic immune response. Further, vaccine derived EHV-1 could be detected in the majority of the intranasally vaccinated horses, potentially impacting diagnostic interpretation of EHV-1 during outbreak situations.

Pediatric Burn Care: How Burn Camps Survived and Thrived During the Coronavirus Pandemic.

Burn camps play a vital role in the recovery of burn survivors by allowing them to develop the confidence and skill sets needed to reintegrate back into society. During the COVID-19 pandemic, burn camps across the United States and Canada could not hold any in-person activities. They had to either pause burn camps or quickly adapt to a virtual online platform. A 37-item electronic survey was developed and emailed to burn camp directors in the United States and Canada to determine what adaptations were necessary during the pandemic. This survey allowed directors to provide details on many facets such as camp format, successes observed, and challenges encountered. Twenty-one of 34 (62%) burn camp organizations completed the survey. Thirteen of the 21 (62%) respondents held virtual burn camps in 2020 while everyone else canceled their camps in 2020. The mean number of camps offered per organization decreased from 6.3 in 2019 to 4.7 in 2020. The average number of burn survivors and family members participating also dropped in that same period (2019 aggregate mean = 229.2 vs 2020 aggregate mean = 151.4). Components of virtual camp included video conferencing platforms, "camp-in-a-box" activities, and some prerecorded sessions. Most camp directors believed that their campers were satisfied with the virtual format. Factors allowing for a successful virtual camp included an effective online platform, scheduling adequate duration of programs, and appropriate staffing levels. Most common barriers to an effective virtual camp were participant engagement, special needs/accessibility concerns, and staff effectiveness in this format. While challenging, burn camps can be held in a virtual format successfully with proper planning, staff training, and support of campers and their families.

Seroprevalence of SARS-CoV-2 in 1186 Equids Presented to a Veterinary Medical Teaching Hospital in California from 2020 to 2022.

While some companion animals have been shown to be susceptible to SARS-CoV-2, their role in the COVID-19 pandemic has remained poorly investigated. Equids are susceptible to SARS-CoV-2 based on the similarity of the human ACE-2 receptor and reports of infection. Clinical disease and prevalence factors associated with SARS-CoV-2 infection in equids have not yet been investigated. The aim of this study was to determine the seroprevalence of SARS-CoV-2 and selected prevalence factors in 1186 equids presented for various conditions to a Veterinary Medical Teaching Hospital over a two-year period. Blood samples were tested for SARS-CoV-2 antibodies using an ELISA targeting the receptor binding domain (RBD) of the SARS-CoV-2 spike protein. Further, selected prevalence factors (season, age, breed, sex, presenting complaint) were retrieved from the medical records. No information was available on whether the horses had come into contact with COVID-19-positive individuals. Among the study animals, 42/1186 (3.5%) horses had detectable SARS-CoV-2 antibodies. Amongst the prevalence factors investigated, only seasonality (spring) was associated with a greater frequency of seropositivity to SARS-CoV-2. Horses with medical and surgical complaints were more likely to test seropositive to SARS-CoV-2 compared to horses presented for routine health care procedures, suggesting more frequent and/or longer interactions with individuals with COVID-19. While horses can become infected with SARS-CoV-2 via the occasional spillover from COVID-19 individuals, clinical disease expression remains subclinical, making horses an unlikely contributor to the spread of SARS-CoV-2.

Prevalence and geographic distribution of Babesia conradae and detection of Babesia vogeli in free-ranging California coyotes (Canis latrans).

Babesia species are intraerythrocytic piroplasms that can result in disease characterized by hemolytic anemia and thrombocytopenia. Of the 5 species that are known to infect canids in the United States, Babesia conradae is most frequently diagnosed in California, and Babesia vogeli is prevalent in the US. Despite the recent re-emergence of B. conradae, the mechanism of transmission is not known. Coyotes (Canis latrans) have been a proposed reservoir of disease, and previous work has shown that dogs with known aggressive interactions with coyotes are at greater risk for infection. This study aimed to determine the prevalence of B. conradae in wild coyote populations in California to assess the viability of coyotes as a potential source of infection for domestic dogs. Four hundred and sixty-one splenic samples were obtained during post-mortem examination of coyote carcasses from Southern California, Fresno, and Hopland. Demographic data including age, sex, cause of death, and urbanity were collected for each coyote. DNA was extracted from samples and amplified using real-time PCR with primers specific for the B. conradae ITS-2 gene. The 18S gene was amplified and sequenced using conventional PCR primers specific to the Babesia genus from any coyotes positive for B. conradae. In total, 22 coyotes tested positive for B. conradae in Fresno (n = 15), Orange (n = 4), San Bernardino (n = 1), and Los Angeles counties (n = 1) with an overall prevalence of 4.8%. Coyotes from Fresno (P<.01) and rural coyotes (P<.01) were significantly more likely to be infected with B. conradae. Ten of 14 samples sequenced were 99-100% homologous to B. conradae, and 4 samples were 100% homologous with B. vogeli DNA indicating co-infection with both pathogens. This study demonstrates that coyotes can become infected and harbor B. conradae and B. vogeli and should be investigated as a possible source of infection in domestic dogs.

Frequency of Detection of Respiratory Pathogens in Clinically Healthy Show Horses Following a Multi-County Outbreak of Equine Herpesvirus-1 Myeloencephalopathy in California.

Actively shedding healthy horses have been indicated as a possible source of respiratory pathogen outbreak, transmission, and spread. Using nasal swabs from clinically healthy sport horses submitted for qPCR testing after an outbreak of equine herpesvirus-1 (EHV-1) myeloencephalopathy (EHM) in the spring of 2022, this study aimed to identify the rate of clinically healthy horses shedding common and less characterized respiratory pathogens within the sport horse population to better understand their role in outbreaks. Swabs were collected during a required quarantine and testing period, according to the United States Equestrian Federation (USEF), and showed return-to-competition requirements. Common respiratory pathogens, such as equine influenza virus (EIV), EHV-4, and equine rhinitis B virus (ERBV), were found at low but stable frequencies within previously reported ranges, whereas EHV-1 and Streptococcus equi subspecies equi (S. equi) were found at or above previously reported frequencies. Less characterized respiratory pathogens, such as EHV-2, EHV-5, and S. equi subspecies zooepidemicus (S. zooepidemicus), were found within previously reported ranges. Common respiratory pathogens, especially EHV-1 following the multiple EHM outbreaks, were found to be circulating in clinically healthy sport horse populations, reflecting their silent transmission. The strategy of quarantine and EHV-1 qPCR testing of clinically healthy horses was successful at eliminating additional EHM outbreaks and facilitating safe return to competition with no reported respiratory disease outbreaks following the subsequent shows in California.

Molecular Monitoring of EHV-1 in Silently Infected Performance Horses through Nasal and Environmental Sample Testing.

While the main goal in the management of an EHM outbreak focuses on identifying early clinical disease in order to physically separate infected horses, little effort is placed towards monitoring healthy horses. The assumption that EHV-1 shedding parallels clinical disease is erroneous, as subclinical shedders have been shown to be actively involved in viral spread. In an attempt to document the frequency of EHV-1 shedders and their impact on environmental contamination, we collected nasal swabs from 231 healthy horses and 203 environmental samples for the testing of EHV-1 by qPCR. Six horses and 28 stalls tested qPCR-positive for EHV-1. There was no association in the EHV-1 qPCR-positive status between nasal and stall swabs. While testing nasal secretions of healthy at-risk horses can detect active shedding at a specific time point, the testing of stall swabs allows to assess the temporal EHV-1 shedding status of a horse. The study results highlight the risk of subclinical EHV-1 shedders and stalls occupied by these horses as sources of infection for susceptible horses. The testing of individual stalls for the presence of EHV-1 may be a more practical approach than the collection of individual nasal swabs for the monitoring and early detection of the circulating virus. The results also highlight the need to improve the cleanliness and disinfection of stalls utilized by performance horses during show events.

Frequency of Detection and Prevalence Factors Associated with Common Respiratory Pathogens in Equids with Acute Onset of Fever and/or Respiratory Signs (2008-2021).

A voluntary biosurveillance program was established in 2008 in order to determine the shedding frequency and prevalence factors for common respiratory pathogens associated with acute onset of fever and/or respiratory signs in equids from the USA. Over a period of 13 years, a total of 10,296 equids were enrolled in the program and nasal secretions were analyzed for the qPCR detection of equine influenza virus (EIV), equine herpesvirus-1 (EHV-1), EHV-4, equine rhinitis A and B virus (ERVs), and Streptococcus equi subspecies equi (S. equi). Single infections with respiratory pathogens were detected in 21.1% of the submissions with EIV (6.8%) and EHV-4 (6.6%) as the two most prevalent viruses, followed by S. equi (4.7%), ERVs (2.3%), and EHV-1 (0.7%). Multiple pathogens were detected in 274 horses (2.7%) and no respiratory pathogens in 7836 horses (76.2%). Specific prevalence factors were determined for each of the six respiratory pathogen groups; most differences were associated with age, breed, and use of the horses, while the clinical signs were fairly consistent between viral and bacterial respiratory infections. Monitoring the frequency of detection of common respiratory pathogens is important in order to gain a better understanding of their epidemiology and to implement management practices aimed at controlling disease spread.

Frequency of Detection of Respiratory Pathogens in Nasal Secretions From Healthy Sport Horses Attending a Spring Show in California.

The objective of this study was to determine detection frequency of respiratory viruses (equine influenza virus [EIV], equine herpesvirus-1 [EHV-1], EHV-2, EHV-4, EHV-5, equine rhinitis A virus [ERAV], ERBV) and bacteria (Streptococcus equi ss. equi[S. equi], S. equi ss. zooepidemicus[S. zooepidemicus]) in 162 nasal secretions and 149 stall swabs from healthy sport horses attending a spring show in California. Nasal and stall swabs were collected at a single time point and analyzed using qPCR. The detection frequency of respiratory pathogens in nasal secretions was 38.9% for EHV-2, 36.4% for EHV-5, 19.7% for S. zooepidemicus, 1.2% for ERBV, 0.6% for S. equi and 0% for EIV, EHV-1, EHV-4 and ERAV. The detection frequency of respiratory pathogens in stall swabs was 65.8% for S. zooepidemicus, 33.5% for EHV-2, 27.5% for EHV-5, 3.3% for EHV-1, 1.3% for EHV-4 and 0% for EIV, ERAV, ERBV and S. equi. Commensal viruses and bacteria were frequently detected in nasal secretions and stall swabs from healthy sport horses. This was in sharp contrast to the subclinical shedding of well-characterized respiratory pathogens. Of interest was the clustering of five EHV-1 qPCR-positive stalls from apparently healthy horses with no evidence of clinical spread. The results highlight the role of subclinical shedders in introducing respiratory pathogens to shows and their role in environmental contamination. The results also highlight the need to improve cleanliness and disinfection of stalls utilized by performance horses during show events.

Nasopulmonary mites (Acari: Halarachnidae) as potential vectors of bacterial pathogens, including Streptococcus phocae, in marine mammals.

Nasopulmonary mites (NPMs) of the family Halarachnidae are obligate endoparasites that colonize the respiratory tracts of mammals. NPMs damage surface epithelium resulting in mucosal irritation, respiratory illness, and secondary infection, yet the role of NPMs in facilitating pathogen invasion or dissemination between hosts remains unclear. Using 16S rRNA massively parallel amplicon sequencing of six hypervariable regions (or "16S profiling"), we characterized the bacterial community of NPMs from 4 southern sea otters (Enhydra lutris nereis). This data was paired with detection of a priority pathogen, Streptococcus phocae, from NPMs infesting 16 southern sea otters and 9 California sea lions (Zalophus californianus) using nested conventional polymerase chain reaction (nPCR). The bacteriome of assessed NPMs was dominated by Mycoplasmataceae and Vibrionaceae, but at least 16 organisms with pathogenic potential were detected as well. Importantly, S. phocae was detected in 37% of NPM by nPCR and was also detected by 16S profiling. Detection of multiple organisms with pathogenic potential in or on NPMs suggests they may act as mechanical vectors of bacterial infection for marine mammals.

Higher risk of auto versus pedestrian crashes in school-age children on school days.

BACKGROUND: This study examines the rates of pediatric auto versus pedestrian collision (APCs) and determined ages and periods of greatest risk. We hypothesized that the rate of APC in children would be higher on school days and in the timeframes correlating with travel to and from school. METHODS: Retrospective case-control study of APC on school and nonschool days for patients younger than 18 years at an urban Level II pediatric trauma center from January 2011 to November 2019. Frequency of APC by hour of the day was plotted overall, for school versus nonschool days and for age groups: 0 year to 4 years, 5 years to 9 years, 10 years to 13 years, and 14 years to 17 years. t Test was used with a p value less than 0.05, which was considered significant. RESULTS: There were 441 pediatric APC in the study period. Frequency of all APC was greater on school days (0.174 vs. 0.101; relative risk [RR], 1.72, p < 0.001), and APC with Injury Severity Score greater than 15 (0.039 vs. 0.024; p = 0.014; RR, 1.67; 95% confidence interval, 1.10-2.56). Comparing school day with nonschool day, the 0-year to 4-year group had no significant difference in APC frequency (0.021 vs. 0.014; p = 0.129), APC frequency was higher on school days in all other age groups: 5 years to 9 years (0.036 vs. 0.019; RR, 1.89; p = 0.0134), 10 years to 13 years (0.055 vs. 0.024; RR, 2.29; p < 0.001), and 14 years to 17 years (0.061 vs. 0.044; RR, 1.39; p = 0.045). The greatest increase in APC on school days was in the 10-year to 13-year age group. DISCUSSION: All school age children are at higher risk of APC on school days. The data support our hypothesis that children are at higher risk of APC during transit to and from school. The age 10-year to 13-year group had a 129% increase in APC frequency on school days. This age group should be a focus of injury prevention efforts. LEVEL OF EVIDENCE: Prognostic and Epidemiologic; Level IV.

Investigation of the Use of Non-Invasive Samples for the Molecular Detection of EHV-1 in Horses with and without Clinical Infection.

The purpose of this study was to explore sampling options for a reliable and logistically more feasible protocol during a large EHV-1 outbreak. Seventeen horses with clinical infection as well as nineteen healthy herdmates, all part of an EHM outbreak, were enrolled in the study. Each horse was sampled two-four times at intervals of 2-6 days during the outbreak. All samples were collected using 6'' rayon-tipped swabs. Nasal secretions were used as the diagnostic sample of choice. Additional samples, including swabs from the muzzle/nares, swabs from the front limbs, rectal swabs, swabs of the feed bin, and swabs of the water troughs were collected as well. All swabs were tested for the presence of EHV-1 by qPCR. With the exception of two EHV-1 qPCR-positive swabs from two different horses, all remaining swabs collected from healthy herdmates tested qPCR-negative for EHV-1. For horses with clinical infection, EHV-1 was detected in 31 nasal swabs, 30 muzzle/nares swabs, 7 front limb swabs, 7 feeders, 6 water troughs and 6 rectal swabs. Not all positive muzzle/nares swabs correlated with a positive nasal swab from the same set, however, and all other positive swabs did correlate with a positive nasal swab in their respective set. The agreement between nasal swabs and muzzle/nares swabs was 74%. The sampling of non-invasive swabs from the muzzle/nares should facilitate the identification of EHV-1 shedders during an outbreak, allowing for prompt isolation and implementation of biosecurity measures.