Genetic diversity and phylogenetic relationships between Leishmania infantum from dogs,humans and wildlife in south‐east Spain

Leishmania infantum causes human and canine leishmaniosis. The parasite, transmitted by phlebotomine sand flies, infects species other than dogs and people, including wildlife, although their role as reservoirs of infection remains unknown for most species. Molecular typing of parasites to investigate genetic variability and evolutionary proximity can help understand transmission cycles and designing control strategies. We investigated Leishmania DNA variability in kinetoplast (kDNA) and internal transcribed spacer 2 (ITS2) sequences in asymptomatically infected wildlife (n = 58) and symptomatically and asymptomatically infected humans (n = 38) and dogs (n = 15) from south‐east Spain, using single nucleotide polymorphisms (SNPs) and in silico restriction fragment length polymorphism (RFLP) analyses. All ITS2 sequences (n = 76) displayed a 99%–100% nucleotide identity with a L. infantum reference sequence, except one with a 98% identity to a reference Leishmania panamensis sequence, from an Ecuadorian patient. No heterogeneity was recorded in the 73 L. infantum ITS2 sequences except for one SNP in a human parasite sequence. In contrast, kDNA analysis of 44 L. infantum sequences revealed 11 SNP genotypes (nucleotide variability up to 4.3%) and four RFLP genotypes including B, F and newly described S and T genotypes. Genotype frequency was significantly greater in symptomatic compared to asymptomatic individuals. Both methods similarly grouped parasites as predominantly or exclusively found in humans, in dogs, in wildlife or in all three of them. Accordingly, the phylogenetic analysis of kDNA sequences revealed three main clusters, two as a paraphyletic human parasites clade and a third including dogs, people and wildlife parasites. Results suggest that Leishmania infantum genetics is complex even in small geographical areas and that, probably, several independent transmission cycles take place simultaneously including some connecting animals and humans. Investigating these transmission networks may be useful in understanding the transmission dynamics, infection risk and therefore in planning L. infantum control strategies.     

Prevalence of the Bacterium Coxiella burnetii in Wild Rodents from a Canadian Natural Environment Park

Zoonotic diseases impact both wild and domestic animal populations and can be transmitted to humans through close contact with animal species. Reservoir species acting as vectors are major traffickers of disease. Rodents contribute to the transmission of Coxiella burnetii although little is known about its prevalence in wild animal populations. DNA was extracted from genital swabs collected from woodland jumping mice, deer mice, Southern red‐backed voles, Eastern chipmunks, North American red squirrels, as well as Southern and Northern flying squirrels collected from Algonquin Park, Canada. The presence of C. burnetii was determined through real‐time PCR. All species sampled had some prevalence of infection, except Eastern chipmunks, indicating wild rodents in Algonquin Park are reservoirs for C. burnetii. Emerging zoonotic diseases are linked to increasing globalization. Contact amongst individuals increases as crowding, habitat loss and fragmentation increase within wild spaces. Parks often act as a last refuge for wildlife but may also be an important transmission zone of wildlife disease to humans. Investigations that attempt to discover wild reservoir species of zoonotic disease are critically important to understanding the risk of pathogen exchange between wild and human populations.     

Raccoon roundworm (Baylisascaris procyonis) as an occupational hazard: 1. Knowledge of B. procyonis and attitudes towards it and other zoonoses among wildlife rehabilitators

Wildlife rehabilitators are at risk of zoonotic diseases because they often have prolonged contact with many species of wildlife and their bodily fluids. Raccoon roundworm (Baylisascaris procyonis) is a common zoonotic parasite of raccoons that has the potential to cause severe or fatal neurologic disease in a broad variety of hosts if the eggs within raccoon faeces are ingested. We administered an online survey to wildlife rehabilitators to assess their knowledge regarding aspects of transmission, biology and disease caused by B. procyonis, and also to evaluate attitudes towards wildlife diseases and B. procyonis as an occupational hazard. Knowledge was assessed using multiple choice and true–false questions; attitudes were measured using Likert‐type items. A total of 659 complete or near‐complete responses (missing fewer than three knowledge or attitudes items and/or non‐response to some demographic fields) were collected. The median knowledge score was 7/14 questions correct (range: 0–14 correct). Generally, individuals with higher levels of education and rehabilitation experience, veterinary professionals and those who are members of professional wildlife rehabilitation groups scored above the median significantly more often (p < .01). Significantly more rehabilitators who were located in the south‐east and those with part‐time or infrequent commitments scored below the median overall knowledge score. There was general agreement that B. procyonis is a health risk of rehabilitators and that measures should be taken to control transmission to people and animals. Some factors explaining differences in attitudes include setting of rehabilitation (home versus animal care facility), veterinary profession, region, membership in a wildlife rehabilitation group and rehabilitation of raccoons. Findings emphasize the importance of awareness and mentorship to inform rehabilitators on the potential risks of B. procyonis and other potential zoonoses within captive wildlife settings, and the important role of professional wildlife rehabilitator groups in disseminating educational materials.     

Trypanosoma cruzi: adaptation to its vectors and its hosts

American trypanosomiasis is a parasitic zoonosis that occurs throughout Latin America. The etiological agent, Trypanosoma cruzi, is able to infect almost all tissues of its mammalian hosts and spreads in the environment in multifarious transmission cycles that may or not be connected. This biological plasticity, which is probably the result of the considerable heterogeneity of the taxon, exemplifies a successful adaptation of a parasite resulting in distinct outcomes of infection and a complex epidemiological pattern. In the 1990s, most endemic countries strengthened national control programs to interrupt the transmission of this parasite to humans. However, many obstacles remain to the effective control of the disease. Current knowledge of the different components involved in elaborate system that is American trypanosomiasis (the protozoan parasite T. cruzi, vectors Triatominae and the many reservoirs of infection), as well as the interactions existing within the system, is still incomplete. The Triatominae probably evolve from predatory reduvids in response to the availability of vertebrate food source. However, the basic mechanisms of adaptation of some of them to artificial ecotopes remain poorly understood. Nevertheless, these adaptations seem to be associated with a behavioral plasticity, a reduction in the genetic repertoire and increasing developmental instability.     

Modelling American Trypanosomiasis in an Endemic Zone: Application to the Initial Spread of Household Infection in the Argentine Chaco

The complex dynamics of Trypanosoma cruzi infection (Chagas disease) involves different actors and multiple transmission routes. Based on the information currently available, here, we propose a new and more comprehensive model to better understand the dynamics of the infection. This mathematical deterministic model was formulated considering: (i) the three clinical forms in humans: acute, chronic indeterminate and chronic with determinate pathology, (ii) the three main modes of transmission in the human population: vector‐borne, congenital and transfusional, (iii) populations of triatomines and dogs as the main domestic reservoirs of T. cruzi and (iv) open populations. A numerical simulation was also performed to estimate the initial spread of the infection in a typical rural household in the endemic zone of the Argentine Gran Chaco. We also analysed the incidence of infected individuals corresponding to each of the three species (humans/triatomines/dogs) over times until the appearance of the first case in the other species. The model predicts that, in the absence of control measures, a few infected individuals are sufficient for the establishment and dispersion of the infection in all the inhabitants of the household. The model proposed and the results obtained allow describing the consequences of the presence of infected individuals in any of the three species considered in the dynamics and the output of the infection.     

Toxoplasma gondii infection in Colombia with a review of hosts and their ecogeographic distribution

Toxoplasma gondii is one of the most prevalent zoonotic protozoan parasites among warm‐blooded animal populations (humans included) around the world, causing multiple clinic manifestations including death in the most severe cases of infection. Due to the versatile life cycle of T. gondii and its diversity of potential hosts, there is a common perception that natural areas and wildlife are highly prevalent reservoirs for the parasite; however, information and reports of the parasite on wildlife populations in Colombia are scarce. Using PRC‐based detection analyses of the B1 gene, we evaluated the presence of T. gondii in 49 native small mammal species (10% of the mammal species of Colombia) from 4 different undisturbed natural habitats. Additionally, to understand the ecogeographical distribution of the parasite in Colombia, we developed a literature search of infection reports including information on the host species, density of records and occurrence patterns (using landcover and ecoregions) in natural, rural and urban areas. Our literature review showed a total of 8,103 reports of T. gondii for Colombia of which 86% were related to humans, and 14% to non‐human mammals and other categories, with just a single report associated to wildlife; additionally, 82% of all reports were associated to urban areas whereas only 18% to rural sites. Based on the negative results for the presence of T. gondii in our PCR‐based analyses and our literature search, we suggest that T. gondii has a synanthropic distribution in Colombia occurring in ecoregions as variable as the xeric scrubs in the northern lowlands and humid montane Andean forests, also we show a lack of information on the parasite relationship with wildlife, a concerning fact given that zoonoses are the leading mechanism for the emergence of infectious diseases.     

The transmission of Cowdria ruminantium by Amblyomma sparsum

Transmission of Cowdria ruminantium (heartwater) by nymphs of Amblyomma sparsum has been demonstrated. Adults of the same tick species failed to transmit the disease after feeding on infected sheep in either the larval or the nymphal stage, and there was no transovarian transmission. A. sparsum seldom parasitizes domestic livestock but could be of importance in maintaining reservoirs of heartwater infection in wildlife populations.     

Cattle Drive Salmonella Infection in the Wildlife–Livestock Interface

The genus Salmonella is found throughout the world and is a potential pathogen for most vertebrates. It is also the most common cause of food‐borne illness in humans, and wildlife is an emerging source of food‐borne disease in humans due to the consumption of game meat. Wild boar is one of the most abundant European game species and these wild swine are known to be carriers of zoonotic and food‐borne pathogens such as Salmonella. Isolation of the pathogen, serotyping and molecular biology are necessary for elucidating epidemiological connections in multi‐host populations. Although disease management at population level can be addressed using a number of different strategies, such management is difficult in free‐living wildlife populations due to the lack of experience with the wildlife–livestock interface. Herein, we provide the results of a 4‐year Salmonella survey in sympatric populations of wild boar and cattle in the Ports de Tortosa i Beseit National Game Reserve (NE Spain). We also evaluated the effects of two management strategies, cattle removal and increased wild boar harvesting (i.e. by hunting and trapping), on the prevalence of the Salmonella serovar community. The serovars Meleagridis and Anatum were found to be shared by cattle and wild boar, a finding that was confirmed by 100% DNA similarity patterns using pulse field gel electrophoresis. Cattle removal was more efficient than the culling of wild boar as a means of reducing the prevalence of shared serotypes, which underlines the role of cattle as a reservoir of Salmonella for wild boar. To our knowledge, this is the first attempt to manage Salmonella in the wild, and the results have implications for management.     

Antimicrobial Resistance in Wildlife: Implications for Public Health

The emergence and spread of antimicrobial‐resistant (AMR) bacteria in natural environments is a major concern with serious implications for human and animal health. The aim of this study was to determine the prevalence of AMR Escherichia coli (E. coli) in wild birds and mammalian species. Thirty faecal samples were collected from each of the following wildlife species: herring gulls (Larus argentatus), black‐headed gulls (Larus ridibundus), lesser black‐back gulls (Larus fuscus), hybrid deer species (Cervus elaphus x Cervus nippon) and twenty‐six from starlings (Sturnus vulgaris). A total of 115 E. coli isolates were isolated from 81 of 146 samples. Confirmed E. coli isolates were tested for their susceptibility to seven antimicrobial agents by disc diffusion. In total, 5.4% (8/146) of samples exhibited multidrug‐resistant phenotypes. The phylogenetic group and AMR‐encoding genes of all multidrug resistance isolates were determined by PCR. Tetracycline‐, ampicillin‐ and streptomycin‐resistant isolates were the most common resistant phenotypes. The following genes were identified in E. coli: bla_TEM, strA, tet(A) and tet(B). Plasmids were identified in all samples that exhibited multidrug‐resistant phenotypes. This study indicates that wild birds and mammals may function as important host reservoirs and potential vectors for the spread of resistant bacteria and genetic determinants of AMR.     

Molecular and Statistical Analysis of Campylobacter spp. and Antimicrobial‐Resistant Campylobacter Carriage in Wildlife and Livestock from Ontario Farms

The objectives of this study were to (i) compare the carriage of Campylobacter and antimicrobial‐resistant Campylobacter among livestock and mammalian wildlife on Ontario farms, and (ii) investigate the potential sharing of Campylobacter subtypes between livestock and wildlife. Using data collected from a cross‐sectional study of 25 farms in 2010, we assessed associations, using mixed logistic regression models, between Campylobacter and antimicrobial‐resistant Campylobacter carriage and the following explanatory variables: animal species (beef, dairy, swine, raccoon, other), farm type (swine, beef, dairy), type of sample (livestock or wildlife) and Campylobacter species (jejuni, coli, other). Models included a random effect to account for clustering by farm where samples were collected. Samples were subtyped using a Campylobacter‐specific 40 gene comparative fingerprinting assay. A total of 92 livestock and 107 wildlife faecal samples were collected, and 72% and 27% tested positive for Campylobacter, respectively. Pooled faecal samples from livestock were significantly more likely to test positive for Campylobacter than wildlife samples. Relative to dairy cattle, pig samples were at significantly increased odds of testing positive for Campylobacter. The odds of isolating Campylobacter jejuni from beef cattle samples were significantly greater compared to dairy cattle and raccoon samples. Fifty unique subtypes of Campylobacter were identified, and only one subtype was found in both wildlife and livestock samples. Livestock Campylobacter isolates were significantly more likely to exhibit antimicrobial resistance (AMR) compared to wildlife Campylobacter isolates. Campylobacter jejuni was more likely to exhibit AMR when compared to C. coli. However, C. jejuni isolates were only resistant to tetracycline, and C.  coli isolates exhibited multidrug resistance patterns. Based on differences in prevalence of Campylobacter spp. and resistant Campylobacter between livestock and wildlife samples, and the lack of similarity in molecular subtypes and AMR patterns, we concluded that the sharing of Campylobacter species between livestock and mammalian wildlife was uncommon.     

Spatiotemporal interactions between wild boar and cattle: implications for cross-species disease transmission

Controlling infectious diseases at the wildlife/livestock interface is often difficult because the ecological processes driving transmission between wildlife reservoirs and sympatric livestock populations are poorly understood. Thus, assessing how animals use their environment and how this affects interspecific interactions is an important factor in determining the local risk for disease transmission and maintenance. We used data from concurrently monitored GPS-collared domestic cattle and wild boar (Sus scrofa) to assess spatiotemporal interactions and associated implications for bovine tuberculosis (TB) transmission in a complex ecological and epidemiological system, Doñana National Park (DNP, South Spain). We found that fine-scale spatial overlap of cattle and wild boar was seasonally high in some habitats. In general, spatial interactions between the two species were highest in the marsh-shrub ecotone and at permanent water sources, whereas shrub-woodlands and seasonal grass-marshlands were areas with lower predicted relative interactions. Wild boar and cattle generally used different resources during winter and spring in DNP. Conversely, limited differences in resource selection during summer and autumn, when food and water availability were limiting, resulted in negligible spatial segregation and thus probably high encounter rates. The spatial gradient in potential overlap between the two species across DNP corresponded well with the spatial variation in the observed incidence of TB in cattle and prevalence of TB in wild boar. We suggest that the marsh-shrub ecotone and permanent water sources act as important points of TB transmission in our system, particularly during summer and autumn. Targeted management actions are suggested to reduce potential interactions between cattle and wild boar in order to prevent disease transmission and design effective control strategies.

Electronic supplementary material

The online version of this article (doi:10.1186/s13567-014-0122-7) contains supplementary material, which is available to authorized users.     

A Conceptual Model for the Impact of Climate Change on Fox Rabies in Alaska, 1980–2010

The direct and interactive effects of climate change on host species and infectious disease dynamics are likely to initially manifest\ at latitudinal extremes. As such, Alaska represents a region in the United States for introspection on climate change and disease. Rabies is enzootic among arctic foxes (Vulpes lagopus) throughout the northern polar region. In Alaska, arctic and red foxes (Vulpes vulpes) are reservoirs for rabies, with most domestic animal and wildlife cases reported from northern and western coastal Alaska. Based on passive surveillance, a pronounced seasonal trend in rabid foxes occurs in Alaska, with a peak in winter and spring. This study describes climatic factors that may be associated with reported cyclic rabies occurrence. Based upon probabilistic modelling, a stronger seasonal effect in reported fox rabies cases appears at higher latitudes in Alaska, and rabies in arctic foxes appear disproportionately affected by climatic factors in comparison with red foxes. As temperatures continue a warming trend, a decrease in reported rabid arctic foxes may be expected. The overall epidemiology of rabies in Alaska is likely to shift to increased viral transmission among red foxes as the primary reservoir in the region. Information on fox and lemming demographics, in addition to enhanced rabies surveillance among foxes at finer geographic scales, will be critical to develop more comprehensive models for rabies virus transmission in the region.     

Control of helminth parasites in juvenile horses

Parasite control in juvenile horses remains a substantial challenge for veterinary practitioners and their clients. This age group is at risk for various types of parasitic disease because their worm burdens tend to be larger and more diverse than in mature horses. This contrast is largely attributable to marked differences in relative levels of acquired immunity. Frequent, perennial anthelmintic treatment is not a sustainable approach for parasite control in this age group, but the simple, surveillance‐based parasite control strategies recommended for mature horses are not appropriate for juveniles either. Maneuvering through the early years of a horse's life requires up‐to‐date knowledge about biology and epidemiology of the parasite species in play as well as local evidence regarding the anthelmintic resistance status of each herd. This article provides an overview of the most important helminth parasites to target in a control programme for juvenile horses, and highlights how the target species change as horses age. Young foals (<2 months) are exposed to Strongyloides westeri and Parascaris spp., whereas the primary target parasite in foals between age 2 months and weaning is Parascaris spp. Beyond weaning, the focus shifts away from ascarids, and the targets instead are strongyles and tapeworms. Gasterophilus spp. and Oxyuris equi are also discussed.     

Disease Risk Surface for Coxiella burnetii Seroprevalence in White‐Tailed Deer

Coxiella burnetii is considered a re‐emerging zoonosis in many countries. The bacterium is enzootic in livestock and wildlife in the United States, and environmental contamination is widespread. Despite the potential for exposure, the estimated prevalence of Q fever in humans and animals is not well elucidated, and reported human infections in the United States are relatively rare. Zoonotic transmission of the bacterium is usually associated with abortions in domestic ruminants, but other modes of transmission, such as contact with infected blood and/or milk during field dressing of infected wildlife, have not been thoroughly investigated. Studies of zoonotic pathogen transmission between animal reservoir hosts and humans are usually established in response to documented emergence or re‐emergence of a zoonosis in a particular locale, and, as such, the prevalence of infection in wildlife is largely unknown for many zoonotic pathogens, including C. burnetii. The objective of this study was to create a disease risk surface for C. burnetii seroprevalence in wild white‐tailed deer (Odocoileus virginianus) in New York State. Blood samples were collected from hunter‐harvested deer from across New York State in 2009 and 2010. The samples were processed and tested for the presence of anti‐C. burnetii antibodies via indirect microimmunofluorescence assays using phase II C. burnetii strain RSA439. Overall, 14.50% of the tested white‐tailed deer were C. burnetii phase II seropositive. The dual Kernel density estimation method was used to create a smoothed disease risk surface, which revealed variation in seroprevalence ranging from 0% to 32.0%. Areas of higher seroprevalence were detected in four discrete areas of Central New York and in one additional area in the southwest corner of the northern part of the state. This suggests certain locales where humans may be at increased risk for exposure to the bacterium secondary to contact with potentially infected deer.     

Phenotypic and Genotypic Characterization of Salmonella enterica in Captive Wildlife and Exotic Animal Species in Ohio,USA

The purpose of this study was to investigate the occurrence, antimicrobial resistance patterns, phenotypic and genotypic relatedness of Salmonella enterica recovered from captive wildlife host species and in the environment in Ohio, USA. A total of 319 samples including faecal (n = 225), feed (n = 38) and environmental (n = 56) were collected from 32 different wild and exotic animal species in captivity and their environment in Ohio. Salmonellae were isolated using conventional culture methods and tested for antimicrobial susceptibility with the Kirby–Bauer disc diffusion method. Salmonella isolates were serotyped, and genotyping was performed using the pulsed‐field gel electrophoresis (PFGE). Salmonella was detected in 56 of 225 (24.9%) faecal samples; six of 56 (10.7%) environmental samples and six of 38 (15.8%) feed samples. Salmonella was more commonly isolated in faecal samples from giraffes (78.2%; 36/46), cranes (75%; 3/4) and raccoons (75%; 3/4). Salmonella enterica serotypes of known public health significance including S. Typhimurium (64.3%), S. Newport (32.1%) and S. Heidelberg (5.3%) were identified. While the majority of the Salmonella isolates were pan‐susceptible (88.2%; 60 of 68), multidrug‐resistant strains including penta‐resistant type, AmStTeKmGm (8.8%; six of 68) were detected. Genotypic diversity was found among S. Typhimurium isolates. The identification of clonally related Salmonella isolates from environment and faeces suggests that indirect transmission of Salmonella among hosts via environmental contamination is an important concern to workers, visitors and other wildlife. Results of this study show the diversity of Salmonella serovars and public health implications of human exposure from wildlife reservoirs.     

Factors affecting the flow among domestic, synanthropic and sylvatic cycles of Trichinella

Nematodes of the genus Trichinella are maintained in nature by sylvatic or domestic cycles. The sylvatic cycle is widespread on all continents, from frigid to torrid zones, and it is maintained by cannibalism and scavenging behavior of carnivores. Trichinella is primarily a parasite of carnivorous mammals, although one non-encapsulated species, Trichinella pseudospiralis, has also been detected in birds. The anaerobic metabolism of larvae in nurse cells allows their survival in extremely decayed meat. Encapsulated larvae in the decomposing carcass function similarly to the species-dispersing population of eggs or larvae of other nematodes, suggesting that the natural cycle of Trichinella includes a free-living stage when the parasite is no longer protected by the homeothermy of the host. Consequently, environmental temperature and humidity play an important role in the transmission of Trichinella among wildlife. Of the 10 recognized genotypes of Trichinella, only Trichinella spiralis is transmitted and maintained in a domestic cycle, although it can be present also in wildlife. All other genotypes (Trichinella nativa, Trichinella britovi, T. pseudospiralis, Trichinella murrelli, Trichinella nelsoni and Trichinella papuae, Trichinella T6, T8, and T9) are transmitted and maintained only in a sylvatic cycle. This generalization does not preclude sylvatic species of Trichinella from invading the domestic habitat, and T. spiralis may return to this habitat when humans fail in the management of wildlife and domestic animals. However, the presence of sylvatic genotypes of Trichinella in the domestic habitat represents a "dead-end" for the sylvatic cycle. Synanthropic animals (rats, foxes, mustelids, cats, dogs, etc.) contribute to the flow of sylvatic Trichinella genotypes from wildlife to domestic animals and of T. spiralis from domestic to sylvatic animals. Furthermore, human behavior not only influences the transmission patterns of Trichinella genotypes in the domestic habitat, but also it can contribute to the transmission and spread of this infection among wildlife, for example by improper hunting practices.     

Hepatitis E virus and related viruses in wild,domestic and zoo animals: A review

Hepatitis E is a human disease mainly characterized by acute liver illness, which is caused by infection with the hepatitis E virus (HEV). Large hepatitis E outbreaks have been described in developing countries; however, the disease is also increasingly recognized in industrialized countries. Mortality rates up to 25% have been described for pregnant women during outbreaks in developing countries. In addition, chronic disease courses could be observed in immunocompromised transplant patients. Whereas the HEV genotypes 1 and 2 are mainly confined to humans, genotypes 3 and 4 are also found in animals and can be zoonotically transmitted to humans. Domestic pig and wild boar represent the most important reservoirs for these genotypes. A distinct subtype of genotype 3 has been repeatedly detected in rabbits and a few human patients. Recently, HEV genotype 7 has been identified in dromedary camels and in an immunocompromised transplant patient. The reservoir animals get infected with HEV without showing any clinical symptoms. Besides these well‐known animal reservoirs, HEV‐specific antibodies and/or the genome of HEV or HEV‐related viruses have also been detected in many other animal species, including primates, other mammals and birds. In particular, genotypes 3 and 4 infections are documented in many domestic, wildlife and zoo animal species. In most cases, the presence of HEV in these animals can be explained by spillover infections, but a risk of virus transmission through contact with humans cannot be excluded. This review gives a general overview on the transmission pathways of HEV to humans. It particularly focuses on reported serological and molecular evidence of infections in wild, domestic and zoo animals with HEV or HEV‐related viruses. The role of these animals for transmission of HEV to humans and other animals is discussed.     

The devil is in the details—Host disease and co‐infections are associated with zoonotic pathogen carriage in Norway rats (Rattus norvegicus)

Traditionally, zoonotic pathogen ecology studies in wildlife have focused on the interplay among hosts, their demographic characteristics and their pathogens. But pathogen ecology is also influenced by factors that traverse the hierarchical scale of biological organization, ranging from within‐host factors at the molecular, cellular and organ levels, all the way to the host population within a larger environment. The influence of host disease and co‐infections on zoonotic pathogen carriage in hosts is important because these factors may be key to a more holistic understanding of pathogen ecology in wildlife hosts, which are a major source of emerging infectious diseases in humans. Using wild Norway rats (Rattus norvegicus) as a model species, the purpose of this study was to investigate how host disease and co‐infections impact the carriage of zoonotic pathogens. Following a systematic trap and removal study, we tested the rats for the presence of two potentially zoonotic bacterial pathogens (Bartonella tribocorum and Leptospira interrogans) and assessed them for host disease not attributable to these bacteria (i.e., nematode parasites, and macroscopic and microscopic lesions). We fitted multilevel multivariable logistic regression models with pathogen status as the outcome, lesions and parasites as predictor variables and city block as a random effect. Rats had significantly increased odds of being infected with B. tribocorum if they had a concurrent nematode infection in one or more organ systems. Rats with bite wounds, any macroscopic lesion, cardiomyopathy or tracheitis had significantly increased odds of being infected with L. interrogans. These results suggest that host disease may have an important role in the ecology and epidemiology of rat‐associated zoonotic pathogens. Our multiscale approach to assessing complex intrahost factors in relation to zoonotic pathogen carriage may be applicable to future studies in rats and other wildlife hosts.     

A systematic review of leptospirosis on wild animals in Latin America

Leptospirosis is a bacterial systemic infection which affects domestic animals and wildlife, as well as humans. Many wild animals act as reservoirs of leptospires. Nevertheless, the real role of wildlife animals as source of infection to livestock and humans, as well as the most important reservoirs and leptospiral strains remains unclear. This systematic review assesses the available data about wildlife and their biomes in Latin America, concerning to leptospiral infection. In addition, we discuss the development of the research on leptospirosis in wildlife in this region. After the application of exclusion criteria, 79 papers were analyzed, comprising 186 species, 122 genus, 53 families, and 19 orders from four classes. Mammals were the most studied class, followed by Amphibian, Reptile, and Aves. The Icterohaemorrhagiae serogroup was predominant in most biomes and many orders. A small number of antigens detected the majority of seroreactive animals of each class, and a smaller panel may be used at microscopic agglutination test. Further studies must always consider edaphoclimatic conditions besides only host class or species, in order to obtain a broader understanding of the wild epidemiological cycle of leptospirosis in the region. In conclusion, direct and indirect evidences demonstrate that leptospirosis is largely widespread among wildlife in all biomes of Latin America. Moreover, more research on the role of wildlife on the epidemiology of leptospirosis and its impact on livestock and public health are required, particularly focusing on direct detection of the agent.