Household environment and animal fecal contamination are critical modifiers of the gut microbiome and resistome in young children from rural Nicaragua.

BACKGROUND: Early life plays a vital role in the development of the gut microbiome and subsequent health. While many factors that shape the gut microbiome have been described, including delivery mode, breastfeeding, and antibiotic use, the role of household environments is still unclear. Furthermore, the development of the gut antimicrobial resistome and its role in health and disease is not well characterized, particularly in settings with water insecurity and less sanitation infrastructure. RESULTS: This study investigated the gut microbiome and resistome of infants and young children (ages 4 days-6 years) in rural Nicaragua using Oxford Nanopore Technology's MinION long-read sequencing. Differences in gut microbiome diversity and antibiotic resistance gene (ARG) abundance were examined for associations with host factors (age, sex, height for age z-score, weight for height z-score, delivery mode, breastfeeding habits) and household environmental factors (animals inside the home, coliforms in drinking water, enteric pathogens in household floors, fecal microbial source tracking markers in household floors). We identified anticipated associations of higher gut microbiome diversity with participant age and vaginal delivery. However, novel to this study were the significant, positive associations between ruminant and dog fecal contamination of household floors and gut microbiome diversity. We also identified greater abundance of potential pathogens in the gut microbiomes of participants with higher fecal contamination on their household floors. Path analysis revealed that water quality and household floor contamination independently and significantly influenced gut microbiome diversity when controlling for age. These gut microbiome contained diverse resistome, dominated by multidrug, tetracycline, macrolide/lincosamide/streptogramin, and beta-lactam resistance. We found that the abundance of ARGs in the gut decreased with age. The bacterial hosts of ARGs were mainly from the family Enterobacteriaceae, particularly Escherichia coli. CONCLUSIONS: This study identified the role of household environmental contamination in the developing gut microbiome and resistome of young children and infants with a One Health perspective. We found significant relationships between host age, gut microbiome diversity, and the resistome. Understanding the impact of the household environment on the development of the resistome and microbiome in early life is essential to optimize the relationship between environmental exposure and human health. Video Abstract.

Patterns of foot-and-mouth disease virus detection in environmental samples in an endemic setting.

Foot-and-Mouth Disease virus (FMDV) is endemic in several regions and is a virus that can persist in the environment dependent on pH, relative humidity (RH), temperature, and matrix (i.e., soil, water, or air). Our previously published analysis of available viral persistence data showed that persistence is likely affected by interactions between RH, temperature, and matrix. Understanding these relationships will aid efforts to eliminate FMD, which has significant impacts on economies and food security. In Cameroon, West Africa, the livestock system consists of mobile (transhumant), transboundary trade and sedentary herds. Studying this system can provide information about the patterns of environmental detection of FMDV RNA that may influence approaches to virus elimination on premises during an outbreak. To improve our understanding of these patterns, we collected samples from individuals, vehicles, and along cattle pathways at three sedentary herds beginning on day one of owner-reported outbreaks, ending by day 30, and tested for the presence of FMD viral RNA using rRT-PCR. Our analysis suggests that detection decreases in soil surface samples with increased distance from herd and time from the first report of disease. Whereas time but not distance decreases detection in air samples. Interaction of RH and temperature suggests increased detection at high temperatures (>24°C) and RH (>75%), providing us with new information about the patterns of FMD viral RNA detection in and around cattle herds that could help to inform targeted virus elimination strategies, such as location and application of disinfectants.

Developing a predictive model for spinal shock in dogs with spinal cord injury.

BACKGROUND: Reduced pelvic limb reflexes in dogs with spinal cord injury typically suggests a lesion of the L4-S3 spinal cord segments. However, pelvic limb reflexes might also be reduced in dogs with a T3-L3 myelopathy and concurrent spinal shock. HYPOTHESIS/OBJECTIVES: We hypothesized that statistical models could be used to identify clinical variables associated with spinal shock in dogs with spinal cord injuries. ANIMALS: Cohort of 59 dogs with T3-L3 myelopathies and spinal shock and 13 dogs with L4-S3 myelopathies. METHODS: Data used for this study were prospectively entered by partner institutions into the International Canine Spinal Cord Injury observational registry between October 2016 and July 2019. Univariable logistic regression analyses were performed to assess the association between independent variables and the presence of spinal shock. Independent variables were selected for inclusion in a multivariable logistic regression model if they had a significant effect (P ≤ .1) on the odds of spinal shock in univariable logistic regression. RESULTS: The final multivariable model included the natural log of weight (kg), the natural log of duration of clinical signs (hours), severity (paresis vs paraplegia), and pelvic limb tone (normal vs decreased/absent). The odds of spinal shock decreased with increasing weight (odds ratio [OR] = 0.28, P = .09; confidence interval [CI] 0.07-1.2), increasing duration (OR = 0.44, P = .02; CI 0.21-0.9), decreased pelvic limb tone (OR = 0.04, P = .003; CI 0.01-0.36), and increased in the presence of paraplegia (OR = 7.87, P = .04; CI 1.1-56.62). CONCLUSIONS AND CLINICAL IMPORTANCE: A formula, as developed by the present study and after external validation, could be useful for assisting clinicians in determining the likelihood of spinal shock in various clinical scenarios and aid in diagnostic planning.

Barriers and opportunities for canine rabies vaccination campaigns in Addis Ababa, Ethiopia.

BACKGROUND: Canine rabies is endemic in Ethiopia and presents a significant burden for both animal and human health. We investigate barriers to dog vaccination in Addis Ababa, Ethiopia. These results can be utilized to improve and target future rabies control efforts. METHODOLOGY/PRINCIPLE FINDINGS: During May of 2017, dog owners were surveyed during a free canine rabies vaccination programs that utilized both door-to-door (DtD) and central point (CP) vaccination methods. Surveys collected information on preferences for rabies vaccine delivery and were administered in Amharic. A total of 1057 surveys were completed. Of those surveyed, 62.4 % indicated that their dogs had been vaccinated against rabies within the last year. Commonly reported barriers to vaccination were a lack of awareness that dogs required rabies vaccines (18.1 %) and lack of knowledge about where to find vaccine (15.0 %). The median price owners were willing to pay for vaccination was 25 birr ($0.91 USD) and the median distance willing to travel was 1.0 km; however, 48.9 % of those surveyed during DtD were unwilling to travel at all. We identified 3 classes of respondents who were grouped due to their responses by latent class analysis: 'the Unaware', 'the Vaccinators', and 'the Multiple Barriers'. CONCLUSIONS/SIGNIFICANCE: Although many respondents were willing to pay for rabies vaccine (94.0 %); the preferred cost (median) was less than the actual cost of providing the vaccine. This supports the need for reduced-cost or free vaccine to achieve and sustain the 70 % vaccine coverage target threshold for canine rabies elimination. Additionally, a significant portion (41.5 %) of those surveyed indicated that they were unwilling to travel in order to have their dog vaccinated. The latent class analysis provides useful guidance on how to reach target vaccination. Owners from 'the Unaware' group made up 18.1 % of respondents and their high rate of allowing their dogs to roam identifies them as a prime target for canine health and behavior education. 'The Multiple Barriers' owners reported lower degrees of dog roaming and were substantially more likely to be found by DtD campaigns, possibly because they have limited ability/interest in handling their dogs. These results demonstrate the importance of incorporating DtD vaccination as well as subsidies to maximize vaccine coverage in Addis Ababa.

Insights From Veterinary Disciplinary Actions in California 2017-2019.

There is increasing concern within the veterinary medical community (veterinarians and veterinary students) that disgruntled clients are unfairly leveraging various legal tools against veterinarians. Clinical veterinarians and veterinary students should be aware of the most common types of problems arising within the clinic and how they can lead to formal consumer complaints. The study describes and categorizes with greater detail the types of violations or "causes for discipline" that occur, as well as specific sanctions imposed on veterinarians formally disciplined for standard of care-related violations between 2017 and 2019, for California. In addition, the study calculated the frequency of disciplinary actions and their basic summary statistics regarding the temporal aspect of how lawsuits typically unfold. Using public documents from California, the study describes the analysis and trends for the purpose of providing contextual evidence to inform and guide potential veterinary educational interventions. Although specific to California, this study can serve as a template methodology for comparisons to other states.

Human Health Risks Related to Penicillin G and Oxytetracycline Residues Intake Through Beef Consumption and Consumer Knowledge About Drug Residues in Maroua, Far North of Cameroon.

In Cameroon, a leading livestock production country, previous study highlighted the extensive misuse of veterinary drugs in the Far North Region, where we found the second cattle population of the country. Based on former work describing the presence of penicillin G (PEN) and oxytetracycline (OTC) residues in beef sold for human consumption in Maroua, the capital city of the Far North Region, this study was designed to determine the risk of PEN and OTC residue intake via beef consumption by the population of Maroua and to evaluate the consumer's knowledge on drug residues. Dietary exposure determined here was based on the average consumption of beef (found during a survey of 202 households randomly selected in Maroua) and the average concentration of the two antibiotic residues in beef (obtained after liquid chromatography-tandem mass spectrometry analysis of samples of liver and muscle collected from 202 cattle selected randomly in all the slaughterhouses of Maroua) found in our previous studies. The estimated daily intakes per capita of OTC and PEN residues from beef consumption were 22.81 and 2.37 µg, respectively. The risk was then assessed as high [9.6%; range from 6.4 to 15.4% of acceptable daily intake (ADI)] and considerable (2.2% range from 1.5 to 3.5% of ADI) for PEN and OTC residues, respectively. Based on the mean value, it can be concluded that the estimated risk of antibiotic daily intake through beef in Maroua is high (5.9% of ADI). Also, 98% of the surveyed population is not aware that meat can be contaminated by residues of veterinary drugs administered to slaughter animals. This ignorance would also increase the risk of contamination of the population of Maroua with antibiotic residues. This work clearly highlights the high risk of consuming beef by the population of Maroua. Taking into consideration the evidence of the intake of antibiotic residues from others sources, it is therefore very imperative that measures be taken by the government to ensure food safety in order to guarantee the health of the populations of this region in particular and Cameroon in general, hence the need for the establishment of a national food safety plan.

Environmental persistence of foot-and-mouth disease virus applied to endemic regions.

The consequences of foot-and-mouth disease impact regional economies and food security through animal mortality and morbidity, trade restrictions and burdens to veterinary infrastructure. Despite efforts to control the disease, some regions, mostly in warmer climates, persistently report disease outbreaks. Consequently, it is necessary to understand how environmental factors influence transmission, of this economically devastating disease. Extensive research covers basic aetiology and transmission potential of livestock and livestock products for foot-and-mouth disease virus (FMDV), with a subset evaluating environmental survival. However, this subset, completed in the early to mid-20th century in Northern Europe and the United States, is not easily generalized to today's endemic locations. This review uncovered 20 studies, to assess current knowledge and analyse the effects of environmental variables on FMDV survival, using a Cox proportional hazards (Coxph) model. However, the dataset is limited, for example pH was included in three studies and only five studies reported both relative humidity (RH) and temperature. After dropping pH from the analysis, our results suggest that temperature alone does not describe FMDV survival; instead, interactions between RH and temperature have broader impacts across various conditions. For instance, FMDV is expected to survive longer during the wet season (survival at day 50 is ~90% at 16°C and 86% RH) versus the dry season (survival at day 50 approaches 0% at 16°C and 37.5% RH) or comparatively in the UK versus the Southwestern United States. Additionally, survival on vegetation topped 70% on day 75 when conditions exceeded 20°C with high RH (86%), drastically higher than the survival on inanimate surfaces at the same temperature and RH (~0%). This is important in tropical regions, where high temperatures can persist throughout the year, but RH varies. Therefore, parameter estimates, for disease modelling and control in endemic areas, require environmental survival data from a wider range of conditions.

Characterization of the gut microbiota of Nicaraguan children in a water insecure context.

OBJECTIVES: The gut microbiota varies across human populations. The first years of life are a critical period in its development. While delivery mode and diet contribute to observed variation, the additional contribution of specific environmental factors remains poorly understood. One factor is waterborne enteric pathogen exposure. In this pilot study, we explore the relationship between household water security and the gut microbiota of children. METHODS: From Nicaraguan households (n = 39), we collected drinking water samples, as well as fecal samples from children aged one month to 5.99 years (n = 53). We tested water samples for total coliforms (CFU/mL) and the presence of common enteric pathogens. Composition and diversity of the gut microbiota were characterized by 16S rRNA sequencing. Households were classified as having drinking water that was "low" (<29 CFU/mL) or "high" (≥29 CFU/mL) in coliforms. We used permutational analyses of variance and Mann-Whitney U-tests to identify differences in the composition and diversity of the gut microbiota of children living in these two home types. RESULTS: Insecure access led households to store drinking water and 85% tested positive for coliforms. High concentrations of Salmonella and Campylobacter were found in water and fecal samples. Controlling for age, the gut microbiota of children from high coliform homes were compositionally different and less diverse than those from low coliform homes. CONCLUSIONS: Results indicate that research exploring the ways water insecurity affects human biology should consider the gut microbiome and that investigations of inter-population variation in the gut microbial community of children should consider pathogen exposure and infection.

Using Google Earth™ and Geographical Information System data as method to delineate sample domains for an urban household surveys: the case of Maroua (Far North Region-Cameroon).

BACKGROUND: Getting a random household sample during a survey can be expensive and very difficult especially in urban area and non-specialist. This study aimed to test an alternative method using freely available aerial imagery. METHODS: A gridded map and random selection method was used to select households for interviews. A hundred numbered of points were put along the edges of an updated map of Maroua. Then two numbers were randomly draw at a time and a line was drawn between those two numbers. A lot of different kinds of shapes of different sizes obtained were numbered. Ten shapes were randomly draw and the one selected were considered as 'neighbourhoods'. A grid of 30 m × 30 m was drawn over each and then numbered. 202 grids considered here as households were randomly selected from the ten neighbourhoods for interviews. RESULTS: Out of 202 households visited, only 4 were found to be something other than a house. In addition, 30 sampled households (14.85%) were abandoned or the occupants had relocated elsewhere. This method resulted in an accuracy level of 72%, its advantage is the ability to generate efficient random sample at relatively low cost as well the time required. CONCLUSIONS: The method proposed in this study was efficient and cost-effective when compared to the infield generation of a household inventory or Global Positioning System (GPS) tracking of households. It can then be used by researchers in low-incomes countries where funding for research is a challenge. However, this method needs to train the investigators on how to use the GPS.

Network analyses of transhumance movements and simulations of foot-and-mouth disease virus transmission among mobile livestock in Cameroon.

Foot-and-mouth disease (FMD) affects cloven-hoofed livestock and agricultural economies worldwide. Analyses of the 2001 FMD outbreak in the United Kingdom informed how livestock movement contributed to disease spread. However, livestock reared in other locations use different production systems that might also influence disease dynamics. Here, we investigate a livestock production system known as transhumance, which is the practice of moving livestock between seasonal grazing areas. We built mechanistic models using livestock movement data from the Far North Region of Cameroon. We represented these data as a dynamic network over which we simulated disease transmission and examined three questions. First, we asked what were characteristics of simulated FMDV transmission across a transhumant pastoralist system. Second, we asked how simulated FMDV transmission across a transhumant pastoralist system differed from transmission across this same population held artificially stationary, thereby revealing the effect of movement on disease dynamics. Third, we asked if disease simulations on well-studied theoretical networks are similar to disease simulations on this empirical dynamic network. The results show that the empirical dynamic network was sparsely connected except for an eight-week period in September and October when pastoralists move from rainy season to dry season grazing areas. The mean epidemic size across all 3,744 simulations was 99.9% and the mean epidemic duration was 1.45 years. Disease simulations across the static network showed a smaller mean epidemic size (27.6%) and a similar epidemic duration (1.5 years). Epidemics simulated on theoretical networks showed similar final epidemic sizes (100%) and different mean durations. Our simulations indicate that transhumant livestock systems have the potential to host FMDV outbreaks that affect almost all livestock and last longer than a year. Furthermore, our comparison of empirical and theoretical networks underscores the importance of using empirical data to understand the role of mobility in the transmission of infectious diseases.

Network analyses to quantify effects of host movement in multilevel disease transmission models using foot and mouth disease in Cameroon as a case study.

The dynamics of infectious diseases are greatly influenced by the movement of both susceptible and infected hosts. To accurately represent disease dynamics among a mobile host population, detailed movement models have been coupled with disease transmission models. However, a number of different host movement models have been proposed, each with their own set of assumptions and results that differ from the other models. Here, we compare two movement models coupled to the same disease transmission model using network analyses. This application of network analysis allows us to evaluate the fit and accuracy of the movement model in a multilevel modeling framework with more detail than established statistical modeling fitting methods. We used data that detailed mobile pastoralists' movements as input for 100 stochastic simulations of a Spatio-Temporal Movement (STM) model and 100 stochastic simulations of an Individual Movement Model (IMM). Both models represent dynamic movement and subsequent contacts. We generated networks in which nodes represent camps and edges represent the distance between camps. We simulated pathogen transmission over these networks and tested five network metrics-strength, betweenness centrality, three-step reach, density, and transitivity-to determine which could predict disease simulation outcomes and thereby be used to correlate model simulation results with disease transmission simulations. We found that strength, network density, and three-step reach of movement model results correlated with the final epidemic size of outbreak simulations. Betweenness centrality only weakly correlated for the IMM model. Transitivity only weakly correlated for the STM model and time-varying IMM model metrics. We conclude that movement models coupled with disease transmission models can affect disease transmission results and should be carefully considered and vetted when modeling pathogen spread in mobile host populations. Strength, network density, and three-step reach can be used to evaluate movement models before disease simulations to predict final outbreak sizes. These findings can contribute to the analysis of multilevel models across systems.

Modeling the role of carrier and mobile herds on foot-and-mouth disease virus endemicity in the Far North Region of Cameroon.

Foot and mouth disease virus (FMDV) is an RNA virus that infects cloven-hoofed animals, often produces either epidemic or endemic conditions, and negatively affects agricultural economies worldwide. FMDV epidemic dynamics have been extensively studied, but understanding of drivers of disease persistence in areas in which FMDV is endemic, such as most of sub-Saharan Africa, is lacking. We present a spatial stochastic model of disease dynamics that incorporates a spatial transmission kernel in a modified Gillespie algorithm, and use it to evaluate two hypothesized drivers of endemicity: asymptomatic carriers and the movement of mobile herds. The model is parameterized using data from the pastoral systems in the Far North Region of Cameroon. Our computational study provides evidence in support of the hypothesis that asymptomatic carriers, but not mobile herds, are a driver of endemicity.

Modeling household transmission dynamics: Application to waterborne diarrheal disease in Central Africa.

INTRODUCTION: We describe a method for analyzing the within-household network dynamics of a disease transmission. We apply it to analyze the occurrences of endemic diarrheal disease in Cameroon, Central Africa based on observational, cross-sectional data available from household health surveys. METHODS: To analyze the data, we apply formalism of the dynamic SID (susceptible-infected-diseased) process that describes the disease steady-state while adjusting for the household age-structure and environment contamination, such as water contamination. The SID transmission rates are estimated via MCMC method with the help of the so-called synthetic likelihood approach. RESULTS: The SID model is fitted to a dataset on diarrhea occurrence from 63 households in Cameroon. We show that the model allows for quantification of the effects of drinking water contamination on both transmission and recovery rates for household diarrheal disease occurrence as well as for estimation of the rate of silent (unobserved) infections. CONCLUSIONS: The new estimation method appears capable of genuinely capturing the complex dynamics of disease transmission across various human, animal and environmental compartments at the household level. Our approach is quite general and can be used in other epidemiological settings where it is desirable to fit transmission rates using cross-sectional data. SOFTWARE SHARING: The R-scripts for carrying out the computational analysis described in the paper are available at https://github.com/cbskust/SID.

Risk of environmental exposure to small coccidia from wild canid feces in rural Ohio.

OBJECTIVE To determine the extent of environmental exposure to heteroxenous coccidia from wild canid feces in southeastern Ohio. SAMPLE 285 presumed wild canid fecal samples collected across an ecological system in southeastern Ohio. PROCEDURES Morphological classification and molecular analysis were used to determine the canid genus for collected fecal samples. Microscopic and molecular analysis were used to detect coccidian oocysts and DNA. Several variables were analyzed for associations with coccidian DNA detection or prevalence. RESULTS Coccidian DNA was detected in 51 of 285 (17.9%) fecal samples. Of those positive samples, 1% (95% confidence interval, 0.4% to 3%) had positive results for Hammondia heydorni and none had positive results for Neospora caninum, for an estimated environmental N caninum prevalence of 0% (95% confidence interval, 0% to 7%)/1-km2 hexagonal area evaluated. Morphological classification revealed that 78.9% (225/285) of fecal samples were from coyotes and 17.2% (49/285) were from foxes. No difference in proportions of coccidian DNA-positive fecal samples was identified among canid species. Environmental temperature and fecal freshness were associated with coccidian DNA detection. Land use type, relative canid density, and cattle density were not associated with the prevalence of coccidian DNA-positive samples. CONCLUSIONS AND CLINICAL RELEVANCE The low prevalence of coccidia shed in wild canid feces in this study, including the estimated 0% environmental prevalence of N caninum, suggested that the role of the oocyst environmental phase in coccidia transmission to ruminants is likely minor in rural southeastern Ohio.

Comparison of field surveillance methods for and assessment of factors potentially associated with the presence of free-roaming cats in a mixed-urban environment.

OBJECTIVE To evaluate 2 methods of surveying free-roaming cats (Felis catus) and identify factors potentially associated with the presence of such cats in a mixed-urban environment. ANIMALS Free-roaming cats on and near The Ohio State University campus. PROCEDURES The university campus and surrounding areas were divided into zones classified by land-use category; 100 zones were selected for surveillance of free-roaming cats by the line-transect method (with visual observation). Twenty-three of the 100 zones were selected for surveillance by the trail-camera method (motion-triggered still photography). Food resources in the study site were mapped, and the presence of other animal species was recorded with trail cameras. Potential associations between the number of cat sightings and variables of interest were assessed by statistical methods, RESULTS There were 6 cat sightings in 5 zones and 92 cat sightings in 9 zones with the line-transect and trail-camera methods, respectively. Cats were most frequently detected off campus and in urban land-use zones. The number of cat sightings with trail cameras was significantly correlated with the density of food resources but not wildlife sightings in the area and was significantly greater at night than during the day. CONCLUSIONS AND CLINICAL RELEVANCE The number of sightings with the trail-camera method was substantially higher than that obtained with the line-transect method; however, identification of individual cats was generally not possible, and population size could not be estimated with these methods. Communities considering population control for free-roaming cats should consider the use of trail cameras to identify areas with high free-roaming cat activity and observation at night to gather baseline data. Easily accessible food waste may attract free-roaming cats.

Effect of vaccination on cattle subclinically infected with foot-and-mouth disease virus in Cameroon.

Foot-and-mouth disease (FMD) is one of the most contagious and economically important livestock diseases worldwide. Four serotypes of FMD virus (FMDV; O, A, SAT1, SAT2) circulate in Cameroon, and a trivalent inactivated vaccine against the three most common serotypes (O, A, SAT2) was recently introduced in 2014. The objective of this study was to characterize vaccine performance in cattle under natural hyperendemic conditions in the Adamawa region of Cameroon. Vaccinated cattle (n = 50) and non-vaccinated controls (n = 100) were monitored by serum and oropharyngeal fluid (OPF) sample collection through a 12-month period. Anti-FMDV non-structural protein (anti-NSP) seroprevalence increased from 59.3% (89/150) at the beginning of the study to 85.8% (103/120) at the end of the study, and FMDV RNA was found in 28% (42/150) of animals overall, despite detection of clinical signs of FMD in only 6 non-vaccinated animals. Viral sequence analysis indicated that subclinical infections of FMDV serotypes O and A were present within the study herds during the study period, which was reflected by an overall increase of anti-NSP seroprevalence during the study. There was no association between vaccination status and seroconversion or prevalence of FMDV RNA in OPF. Younger cattle had higher odds of detection of FMDV RNA in OPF, but older animals were more likely to be seropositive. This study suggests vaccination of herds previously exposed to FMDV may help to limit clinical signs and reduce economic losses caused by FMDV. These findings also suggest that subclinical circulation of FMDV occurs in hyperendemic regions regardless of vaccination.

Molecular Epidemiology of Foot-and-Mouth Disease Virus in the Context of Transboundary Animal Movement in the Far North Region of Cameroon.

Transboundary movement of animals is an important mechanism for foot-and-mouth disease virus (FMDV) spread in endemic regions, such as Cameroon. Several transboundary animal trade routes cross the Far North Region of Cameroon, and cattle moved on foot along these routes often come in contact with native (sedentary and transhumant) herds. The purpose of this study was to investigate the role of transboundary trade cattle in the epidemiology of FMDV in the Far North Region of Cameroon. A total of 582 oropharyngeal fluid (OPF) samples were collected from asymptomatic transboundary trade cattle at official border check points and 57 vesicle epithelial tissues were collected from clinically affected native cattle in the Far North Region of Cameroon during 2010-2014. Viral protein 1 (VP1) coding sequences were obtained from 6 OPF samples from transboundary cattle (4 serotype O, 2 serotype SAT2) and 19 epithelial tissue samples from native cattle (7 serotype O, 3 serotype SAT2, 9 serotype A). FMDV serotype O viruses belonged to two topotypes (East Africa-3 and West Africa), and phylogenetic analyses suggested a pattern of continuous transmission in the region. Serotype SAT2 viruses belonged to a single topotype (VII), and phylogenetic analysis suggested a pattern of repeated introductions of different SAT2 lineages in the region. Serotype A viruses belonged to topotype AFRICA/G-IV, and the pattern of transmission was unclear. Spearman rank correlation analysis of VP1 coding sequences obtained in this study from transboundary and native cattle showed a positive correlation between genetic distance and time for serotype O (ρ = 0.71, p = 0.003) and between genetic distance and geographic distance for serotype SAT2 (ρ = 0.54, p = 0.1). These data suggest that transboundary trade cattle participate in the transmission of FMDV in the Far North Region of Cameroon, however the dynamics and direction of transmission could not be determined in this study. Results of this study contribute to the understanding of transboundary FMDV epidemiology in Central Africa and will help to inform control programs in Cameroon and in the region.

Use of a combination of routine hematologic and biochemical test results in a logistic regression model as a diagnostic aid for the diagnosis of hypoadrenocorticism in dogs.

OBJECTIVE To assess the discriminatory value for corticosteroid-induced alkaline phosphatase (CiALP) activity and other variables that can be measured routinely on a CBC and biochemical analysis for the diagnosis of hypoadrenocorticism in dogs. SAMPLE Medical records of 57 dogs with confirmed hypoadrenocorticism and 57 control dogs in which hypoadrenocorticism was suspected but ruled out. PROCEDURES A retrospective case-control study was conducted. Dogs were included if a CBC and complete biochemical analysis had been performed. Dogs with iatrogenic hypoadrenocorticism and dogs treated previously with glucocorticoids were excluded. Cortisol concentration for dogs with hypoadrenocorticism was ≤ 2 µg/dL both before and after ACTH administration. Cortisol concentration for control dogs was > 4 µg/dL before or after ACTH administration. RESULTS Area under the receiver operating characteristic (ROC) curve for CiALP activity was low (0.646; 95% confidence interval, 0.494 to 0.798). Area under the ROC curve for a model that combined the CiALP activity, Na-to-K ratio, eosinophil count, activity of creatine kinase, and concentrations of SUN and albumin was high (0.994; 95% confidence interval, 0.982 to 1.000). Results for this model could be used to correctly classify all dogs, except for 1 dog with hypoadrenocorticism and no electrolyte abnormalities. CONCLUSIONS AND CLINICAL RELEVANCE CiALP activity alone cannot be used as a reliable diagnostic test for hypoadrenocorticism in dogs. Combined results for CiALP activity, Na-to-K ratio, eosinophil count, creatine kinase activity, and concentrations of SUN and albumin provided an excellent means to discriminate between hypoadrenocorticism and diseases that mimic hypoadrenocorticism.

Host species heterogeneity in the epidemiology of Nesopora caninum.

Pathogen transmission across species drives disease emergence; however, mechanisms by which multi-host pathogens cross species boundaries are not well identified. This knowledge gap prevents integrated and targeted control in an epidemiologically continuous ecosystem. Our goal is to describe the impact of host species heterogeneity on the epidemiology of Neospora caninum circulating between livestock and wildlife in southeastern Ohio. We collected biological samples from Père David's deer (Elaphurus davidianus) located at an outdoor wildlife conservation center; from cattle raised at farms adjacent to the center; and from wild white-tailed deer that roamed across farm and center boundaries. We designed nested infectious disease models of competing hypotheses about transmission and used collected data to fit the models, thereby estimating important immunological and transmission quantities which describe the species-specific contribution to the persistence of this pathogen in the community. We applied these data and models to suggest appropriate species-specific disease control methods. Results show that immunity in cattle and Pére David's deer wanes over time, while in white-tailed deer immunity appears to be lifelong. Transmission quantities for cattle were estimated at values below the threshold for an outbreak (Rt < 1), meaning that chains of transmission are not maintained within this population and infections must occur due to reintroduction from an outside source. Pére David's deer and white-tailed deer both could maintain continuous chains of transmission within their group (Rt > 1). Therefore, we propose that control of contact with outside sources will be useful for disease control in cattle; boosting immunity with vaccines might be an avenue to prevent infection in cattle and Père David's deer. White-tailed deer are a potential maintenance host for infection and require further study to determine optimal control methods. Community-level investigations like this allow us to better evaluate heterogeneities in transmission processes that ultimately guide targeted control.