Cross-species Disease Transmission Research Articles

Occurrences and activities of New Zealand sea lions Phocarctos hookeri at non-natal Macquarie Island (1965–1980)

ABSTRACT The distribution of New Zealand sea lions is typically localised to New Zealand and its remote subantarctic islands. However, non-resident male sea lions were seen on Macquarie Island, 650 km from their nearest natal islands, in all months of all years from 1965 to 1980. The majority of the apparently opportunistic sightings were at the northern end of the island. Sightings increased from May to a September-October peak that was coincident with the cessation of breeding activities in the sea lions’ natal range and the period when resident gentoo and royal penguins, and fur and elephant seals aggregated for breeding, all of which are now confirmed prey for New Zealand sea lions on Macquarie Island. The long-term effect of predation pressure from New Zealand sea lions on resident species remains unmeasured. After sleeping, interacting with southern elephant seals was a core sea lion activity. Predation on seabirds and interactions with elephant seals increase the risk of cross-species disease transmission.

Modeling spillover dynamics: understanding emerging pathogens of public health concern

The emergence of infectious diseases with pandemic potential is a major public health threat worldwide. The World Health Organization reports that about 60% of emerging infectious diseases are zoonoses, originating from spillover events. Although the mechanisms behind spillover events remain unclear, mathematical modeling offers a way to understand the intricate interactions among pathogens, wildlife, humans, and their shared environment. Aiming at gaining insights into the dynamics of spillover events and the outcome of an eventual disease outbreak in a population, we propose a continuous time stochastic modeling framework. This framework links the dynamics of animal reservoirs and human hosts to simulate cross-species disease transmission. We conduct a thorough analysis of the model followed by numerical experiments that explore various spillover scenarios. The results suggest that although most epidemic outbreaks caused by novel zoonotic pathogens do not persist in the human population, the rising number of spillover events can avoid long-lasting extinction and lead to unexpected large outbreaks. Hence, global efforts to reduce the impacts of emerging diseases should not only address post-emergence outbreak control but also need to prevent pandemics before they are established.

Xenotransplantation - current social, ethical, religious, and legal aspects

Introduction: Xenotransplantology, the field of transplantation involving organs or tissues between different species, holds great promise for addressing the global organ shortage crisis. However, the development of new technologies without proper legislative preparation raises significant moral and ethical considerations. This paper provides an overview of the current state of xenotransplantology, highlighting its revolutionary potential alongside the moral dilemmas it entails. Aim of the study: The aim of this study is to assess current social, ethical, religious, and legal trends regarding the issue of xenotransplantation. Materials and methods: To obtain up-to-date information concerning trends in xenotransplantation, a review of the PubMed and Google Scholar databases, along with the latest legislative reports in both Europe and Poland, was performed. Conclusions: Firstly, the authors briefly report on the current situation concerning transplantology and the widely spread organ donor crisis. Next, the issue of species boundaries and the moral status of non-human animals is addressed. The assessment of ethical implications of utilizing animals as organ donors is examined, along with the legal acts regulating this issue. Moreover, the authors attempt to evaluate the cultural and religious differences related to this concern. Furthermore, this study discusses the allocation and distribution of xenotransplants, considering issues of justice, fairness, and access to this innovative medical technology. Lastly, the paper delves into the risks and uncertainties associated with xenotransplantation, including the possibility of cross-species disease transmission and intensified course of organ rejection disease.

Latitudinal and anthropogenic effects on the structuring of networks linking blood-feeding flies and their vertebrate hosts.

Biting flies (Diptera) transmit pathogens that cause many important diseases in humans as well as domestic and wild animals. The networks of feeding interactions linking these insects to their hosts, and how they vary geographically and in response to human land-use, are currently poorly documented but are relevant to understanding cross-species disease transmission. We compiled a database of biting Diptera-host interactions from the literature to investigate how key interaction network metrics vary latitudinally and with human land-use. Interaction evenness and H2' (a measure of the degree of network specificity) did not vary significantly with latitude. Compared to near-natural habitats, interaction evenness was significantly lower in agricultural habitats, where networks were dominated by relatively few species pairs, but there was no evidence that the presence of humans and their domesticated animals within networks led to systematic shifts in network structure. We discuss the epidemiological relevance of these results and the implications for predicting and mitigating future spill-over events.

Preventive healthcare among dogs and cats in Chile is positively associated with emotional owner-companion animal bond and socioeconomic factors

Global companion animal population has been increasing as well as the number of dogs and cats being considered as a family member. However, it is unclear whether this close relationship could be associated with higher preventive healthcare in companion animals. Using data from 7,048 questionnaires of dogs and 3,271 of cats from the First National Study on Responsible Companion Animal Ownership, we estimated the proportion of preventive healthcare in companion animals of Chile. We also conducted a general linear mixed-effect regression model to identify socioeconomic factors and indicators of the emotional owners-companion animal bond that could influence owners' practices related to vaccination, parasite control, and veterinary visits. Based on the owner's answers, Chile has a satisfactory overall rates of parasite control (71%) and annual veterinary visits (65%) but a low vaccination coverage of both dogs (39%) and cats (25%). 'Purebred', 'live in urban areas', 'acquired by monetary compensation', and 'dog species' were associated with a higher probability of preventive healthcare in companion animals. Conversely, this probability was lower among senior animals compared to adults, males, and those owned by the Silent Generation or Baby Boomers (i.e., owners born before 1964). 'Sleeping inside', 'acquired for an emotional reason' (e.g., companionship), and 'considered a family member' were positively associated with at least one of assessed preventive measures. Our findings suggest that emotional owner-companion animal bonds could positively impact the frequency and quality of preventive healthcare in dogs and cats. However, owners who totally disagreed that a companion animal is a "family member" were also associated with a higher likelihood of vaccination uptake and veterinary visits for their animals. This highlights that owner's compliance with veterinary preventive healthcare is multifactorial. Chile has a high prevalence of infectious diseases circulating among dogs and cats and increasingly close contacts between owners and companion animals due to emotional bonds. Thus, our study calls for One Health approaches to reduce the risks of cross-species disease transmission. Specifically, increasing vaccination coverage of companion animals in Chile is the most urgent preventive measure needed, especially among cats, males, and older animals. Expand preventive healthcare among dogs and cats will promote public and animal health, including local wildlife that is susceptible to infectious diseases circulating in companion animals.

Oral Sampling of Little Brown Bat (Myotis lucifugus) Maternity Colonies for SARS-CoV-2 in the Northeast and Mid-Atlantic, USA

The potential introduction of SARS-CoV-2, the virus responsible for the COVID-19 pandemic, into North American bat populations is of interest to wildlife managers due to recent disease-mediated declines of several species. Populations of little brown bats (Myotis lucifugus) have collapsed due to white-nose syndrome (WNS), a disease caused by the introduction and spread of the fungal pathogen Pseudogymnoascus destructans (Pd). Throughout much of the United States and southern Canada, large colonies of the species routinely established diurnal roosts in anthropogenic structures, thereby creating the potential for direct human contact and cross-species disease transmission. Given recent declines and the potential for further disease impacts, we collected oral swabs from eight little brown bat maternity colonies to assess the presence and prevalence of SARS-CoV-2 by RT-qPCR analysis. Little brown bat colonies in Maryland (n = 1), New Hampshire (n = 1), New Jersey (n = 2), New York (n = 1), Rhode Island (n = 2), and Virginia (n = 1) were taken during May-August, 2022. From 235 assayed individuals, no bat tested positive for SARS-CoV-2. Our results indicate that little brown bats may not contract SARS-CoV-2 or that the virus persists at undetectable levels in populations of the Mid-Atlantic and Northeast during summer months. Nonetheless, continued monitoring and future work addressing other seasons may still be warranted to conclusively determine infection status.

Reconstructing SARS-CoV-2 infection dynamics through the phylogenetic inference of unsampled sources of infection.

The COVID-19 pandemic has illustrated the importance of infection tracking. The role of asymptomatic, undiagnosed individuals in driving infections within this pandemic has become increasingly evident. Modern phylogenetic tools that take into account asymptomatic or undiagnosed individuals can help guide public health responses. We finetuned established phylogenetic pipelines using published SARS-CoV-2 genomic data to examine reasonable estimate transmission networks with the inference of unsampled infection sources. The system utilised Bayesian phylogenetics and TransPhylo to capture the evolutionary and infection dynamics of SARS-CoV-2. Our analyses gave insight into the transmissions within a population including unsampled sources of infection and the results aligned with epidemiological observations. We were able to observe the effects of preventive measures in Canada’s “Atlantic bubble” and in populations such as New York State. The tools also inferred the cross-species disease transmission of SARS-CoV-2 transmission from humans to lions and tigers in New York City’s Bronx Zoo. These phylogenetic tools offer a powerful approach in response to both the COVID-19 and other emerging infectious disease outbreaks.

Forecasting parasite sharing under climate change.

Species are shifting their distributions in response to climate change. This geographic reshuffling may result in novel co-occurrences among species, which could lead to unseen biotic interactions, including the exchange of parasites between previously isolated hosts. Identifying potential new host-parasite interactions would improve forecasting of disease emergence and inform proactive disease surveillance. However, accurate predictions of future cross-species disease transmission have been hampered by the lack of a generalized approach and data availability. Here, we propose a framework to predict novel host-parasite interactions based on a combination of niche modelling of future host distributions and parasite sharing models. Using the North American ungulates as a proof of concept, we show this approach has high cross-validation accuracy in over 85% of modelled parasites and find that more than 34% of the host-parasite associations forecasted by our models have already been recorded in the literature. We discuss potential sources of uncertainty and bias that may affect our results and similar forecasting approaches, and propose pathways to generate increasingly accurate predictions. Our results indicate that forecasting parasite sharing in response to shifts in host geographic distributions allow for the identification of regions and taxa most susceptible to emergent pathogens under climate change. This article is part of the theme issue 'Infectious disease macroecology: parasite diversity and dynamics across the globe'.

Dynamics in a ratio-dependent eco-epidemiological predator-prey model having cross species disease transmission

We have proposed and analyzed an eco-epidemiological predator-prey interaction model having disease in both the population with ratio-dependent functional response. The total population has been classified into susceptible prey, infected prey, susceptible predator, and infected predator. The infection propagation is considered directly proportional to the number of individuals come in to contact with one infected individual. The predation ability of infected predator is neglected during the disease. The infection is considered to be weak infection in case of predator. Predator can recover themselves due to their natural immune system or application of external curative stimulants. Though such weak infections are not generally considered for study but these cannot be completely ignored. The positivity of the solutions, the existence of various biologically feasible equilibrium points, their stability are investigated. The numerical analysis is carried out with hypothetical set of parameters to substantiate the analytical findings that our model exhibits. The oscillatory coexistence of the species which is very common in nature is observed for disease free as well as coexisting system. The stability nature of the Hopf-bifurcating periodic solutions of the disease free as well as coexisting equilibrium are determined by computing the Lyapunov coefficients. Further, the system undergoes the Bogdanov-Takens bifurcation in two-parameter space around the disease free as well as coexisting equilibrium. It is also observed that the system will be disease free through proper predational strategies.

No excessive mutations in transcription activator-like effector nuclease-mediated α-1,3-galactosyltransferase knockout Yucatan miniature pigs.

ObjectiveSpecific genomic sites can be recognized and permanently modified by genome editing. The discovery of endonucleases has advanced genome editing in pigs, attenuating xenograft rejection and cross-species disease transmission. However, off-target mutagenesis caused by these nucleases is a major barrier to putative clinical applications. Furthermore, off-target mutagenesis by genome editing has not yet been addressed in pigs.MethodsHere, we generated genetically inheritable α-1,3-galactosyltransferase (GGTA1) knockout Yucatan miniature pigs by combining transcription activator-like effector nuclease (TALEN) and nuclear transfer. For precise estimation of genomic mutations induced by TALEN in GGTA1 knockout pigs, we obtained the whole-genome sequence of the donor cells for use as an internal control genome.ResultsIn-depth whole-genome sequencing analysis demonstrated that TALEN-mediated GGTA1 knockout pigs had a comparable mutation rate to homologous recombination-treated pigs and wild-type strain controls. RNA sequencing analysis associated with genomic mutations revealed that TALEN-induced off-target mutations had no discernable effect on RNA transcript abundance.ConclusionTherefore, TALEN appears to be a precise and safe tool for generating genome-edited pigs, and the TALEN-mediated GGTA1 knockout Yucatan miniature pigs produced in this study can serve as a safe and effective organ and tissue resource for clinical applications.

Specificity and seasonal prevalence of anther smut disease Microbotryum on sympatric Himalayan Silene species.

Host sympatry provides opportunities for cross-species disease transmission and compounded disease effects on host population and community structure. Using the Silene-Microbotryum interaction (the castrating anther smut disease), eleven Himalayan Silene species were assessed in regions of high host diversity to ascertain levels of pathogen specificity. We also investigated disease prevalence, seasonal dynamics of infection and flowering patterns in five co-blooming Silene species. We identified several new Microbotryum lineages with varying degrees of specialization that is likely influenced by degrees of host divergence and ecological similarities (i.e. shared pollinator guilds). Affected species had 15%-40% of plants infected by anther smut. Flowering was seasonally overlapping among host species (except for the species pair S.asclepiadea and S.atrocastanea), but diseased flowering onset was earlier than healthy plants, leading to dramatic seasonal shifts in observed disease prevalence. Overlapping distributions and flowering provides opportunities for floral pathogen movement between host species, but host specialization may be constrained by the plant phylogenetic relatedness, adaptation to micro-habitats and difference in pollinator/vector guilds.

Prevention of Cryptosporidium and GIARDIA at the Human/Gorilla/Livestock Interface.

Mountain gorillas (Gorilla beringei beringei) are critically endangered and found in Bwindi Impenetrable Forest and Virunga Volcanoes. Habitat destruction, high human population growth rates, poverty, and disease are threatening the survival of mountain gorillas. A study implemented in 2010 investigated the prevalence of Cryptosporidium and Giardia sps., as part of a long-term gorilla health-monitoring program at Bwindi through regular fecal sample collection, and comparative pathogen analysis at the human/gorilla/livestock interface. Samples collected from habituated and non-habituated gorillas, community-owned livestock herds and people at Bwindi were screened for Cryptosporidium and Giardia sps. using ImmunoSTAT Commercial Field Kit and doubtful samples confirmed with Direct Fluorescence Antibody Test (DFA). Giardia was found in 5.5% of livestock, 40% of symptomatic humans from the local hospital and 9.5% of asymptomatic park staff, but not in gorillas. Cryptosporidium was found in 3.1% of habituated gorillas, 4.7% of livestock, and 62.4% of park staff. Whereas, previous studies have compared Cryptosporidium and Giardia sps. in gorillas and livestock, this is the first study making a comparison in humans, gorillas and livestock. Unlike previous studies in Bwindi and Virungas, no Giardia sp. was found in gorillas. The improving hygiene and sanitation of local communities sharing a habitat with gorillas through Village Health and Conservation Teams (VHCTs) established in 2007, could have contributed to the decreased prevalence of Giardia in this mountain gorilla population. Cryptosporidium sp. only found in the habituated gorillas could be associated with human interaction, similar to previous studies. A subsequent VHCT was selected for each village with positive human samples and where gorillas often range, local health centers were mobilized to educate patients on the health risks of collecting water from unprotected sources and cattle water troughs were built. This paper describes a One Health approach to reducing cross species disease transmission at the human/gorilla/livestock interface.

Domestic mammals facilitate tick-borne pathogen transmission networks in South African wildlife

As changes in the environment have brought wild and domestic animals into closer proximity, cross-species disease transmission has become a major concern in wildlife conservation. The worldwide impacts of tick-borne diseases require an understanding of pathogen transmission dynamics across different host species. Livestock are often kept near protected areas and frequently share habitat with wild animals. The influence of host community composition on tick-borne pathogen transmission remains poorly understood, making it difficult to determine whether sharing habitats with domestic livestock increases tick-borne disease in wildlife populations. We used network analysis to analyse 35,349 collections of 54 tick species in South Africa, treating hosts as nodes and shared tick species as links. Across all life stages, 93 mammalian species were connected by a total of 3105 links. Sheep, goats, and dogs were particularly important domestic species for network connectivity; and for wild animals, soft-skinned, smaller mammals such as the scrub hare. Although South African ticks exhibit some specialization on wild animals, network analysis showed that opportunistic feeding on domestic hosts can lead to shortened transmission pathways and facilitate pathogen spread between mammal species. Mammal species are highly interconnected through the tick species that they share, and domestic mammals significantly increase the risk of disease transmission. These findings support conservation measures that limit contact between domestic and wild mammals to reduce tick-borne disease transmission. Grazing in protected areas must be evaluated in light of disease risks to both domestic and wild animals, and potentially also to people.

Can you catch Ebola from a stork bite? Inductive reasoning influences generalization of perceived zoonosis risk.

Emerging zoonoses are a prominent global health threat. Human beliefs are central to drivers of emerging zoonoses, yet little is known about how people make inferences about risk in such scenarios. We present an inductive account of zoonosis risk perception, suggesting that beliefs about the range of animals able to transmit diseases to each other influence how people generalize risks to other animals and health behaviors. Consistent with our account, in Study 1, we find that participants who endorse higher likelihoods of cross-species disease transmission have stronger intentions to report animal bites. In Study 2, using real-world descriptions of Ebola virus from the WHO and CDC, we find that communications conveying a broader range of animals as susceptible to the virus increase intentions to report animal bites and decrease perceived safety of wild game meat. These results suggest that inductive reasoning principles may be harnessed to modulate zoonosis risk perception and combat emerging infectious diseases.

Cross-species transmission potential between wild pigs, livestock, poultry, wildlife, and humans: implications for disease risk management in North America

Cross-species disease transmission between wildlife, domestic animals and humans is an increasing threat to public and veterinary health. Wild pigs are increasingly a potential veterinary and public health threat. Here we investigate 84 pathogens and the host species most at risk for transmission with wild pigs using a network approach. We assess the risk to agricultural and human health by evaluating the status of these pathogens and the co-occurrence of wild pigs, agriculture and humans. We identified 34 (87%) OIE listed swine pathogens that cause clinical disease in livestock, poultry, wildlife, and humans. On average 73% of bacterial, 39% of viral, and 63% of parasitic pathogens caused clinical disease in other species. Non-porcine livestock in the family Bovidae shared the most pathogens with swine (82%). Only 49% of currently listed OIE domestic swine diseases had published wild pig surveillance studies. The co-occurrence of wild pigs and farms increased annually at a rate of 1.2% with as much as 57% of all farms and 77% of all agricultural animals co-occurring with wild pigs. The increasing co-occurrence of wild pigs with livestock and humans along with the large number of pathogens shared is a growing risk for cross-species transmission.

Tuberculosis Infection: Occurrence and Risk Factors in Presumptive Tuberculosis Patients of the Serengeti Ecosystem in Tanzania.

Background:Cross-species tuberculosis (TB) transmission between humans and animals has been reported for quite a long time in sub-Saharan Africa. Because humans and animals coexist in the same ecosystem, exploring their potential for cross-species transmission and the impact the disease may have on the health of humans, animals, and their products is critical.Objectives:This study aimed to identify risk factors for transmission of TB (Mycobacterium tuberculosis) and to assess the potential for zoonotic TB (Mycobacterium bovis) transmission in the Serengeti ecosystem where humans and animals are in intense contact. Our aim is to create a base for future implementation of appropriate control strategies to limit infection in both humans and animals.Methodology:We administered a semi-structured questionnaire to 421 self-reporting patients to gather information on risk factors and TB occurrence. In a parallel study, researchers screened sputum smears using Ziehl–Neelsen staining and confirmed by mycobacterial culture. We then performed descriptive statistics (Pearson's chi-square test) and logistic regression analysis to establish frequencies, association, and quantification of the risk factors associated with TB cases.Results:Our findings showed 44% (95% confidence interval [CI], 0.40-0.49) of the results were positive from sputum samples collected over a 1-year duration in areas with a high TB burden, particularly the Bunda district, followed by the Serengeti and Ngorongoro districts. Of the culture-positive patients who also had infections other than TB (43/187 patients), 21 (49%) were HIV positive. Contact with livestock products (odds ratio [OR] 6.0; 95% CI, 1.81–19.9), infrequent milk consumption (OR 2.5; 95% CI, 1.42–4.23), cigarette smoking (OR 2.9; 95% CI, 1.19–7.1.2), and alcohol consumption (OR 2.3; 95% CI, 1.22–4.23) were associated with a higher likelihood of TB infection.Conclusion:There was no evidence of direct cross-species transmission of either M tuberculosis or M bovis between humans and animals using the study methods. The absence of cross-species TB transmission could be due to limited chances of contact rather than an inability of cross-species disease transmission. In addition, not all people with presumptive TB are infected with TB, and therefore control strategies should emphasise confirming TB status before administering anti-TB drugs.

Tuberculosis Infection: Occurrence and Risk Factors in Presumptive Tuberculosis Patients of the Serengeti Ecosystem in Tanzania

Background: Cross-species tuberculosis (TB) transmission between humans and animals has been reported for quite a long time in sub-Saharan Africa. Because humans and animals coexist in the same ecosystem, exploring their potential for cross-species transmission and the impact the disease may have on the health of humans, animals, and their products is critical. Objectives: This study aimed to identify risk factors for transmission of TB (Mycobacterium tuberculosis) and to assess the potential for zoonotic TB (Mycobacterium bovis) transmission in the Serengeti ecosystem where humans and animals are in intense contact. Our aim is to create a base for future implementation of appropriate control strategies to limit infection in both humans and animals. Methodology: We administered a semi-structured questionnaire to 421 self-reporting patients to gather information on risk factors and TB occurrence. In a parallel study, researchers screened sputum smears using Ziehl–Neelsen staining and confirmed by mycobacterial culture. We then performed descriptive statistics (Pearson’s chi-square test) and logistic regression analysis to establish frequencies, association, and quantification of the risk factors associated with TB cases. Results: Our findings showed 44% (95% confidence interval [CI], 0.40-0.49) of the results were positive from sputum samples collected over a 1-year duration in areas with a high TB burden, particularly the Bunda district, followed by the Serengeti and Ngorongoro districts. Of the culture-positive patients who also had infections other than TB (43/187 patients), 21 (49%) were HIV positive. Contact with livestock products (odds ratio [OR] 6.0; 95% CI, 1.81-19.9), infrequent milk consumption (OR 2.5; 95% CI, 1.42-4.23), cigarette smoking (OR 2.9; 95% CI, 1.19-7.1.2), and alcohol consumption (OR 2.3; 95% CI, 1.22-4.23) were associated with a higher likelihood of TB infection. Conclusion: There was no evidence of direct cross-species transmission of either M tuberculosis or M bovis between humans and animals using the study methods. The absence of cross-species TB transmission could be due to limited chances of contact rather than an inability of cross-species disease transmission. In addition, not all people with presumptive TB are infected with TB, and therefore control strategies should emphasise confirming TB status before administering anti-TB drugs.

The Impact of Beliefs About Cross-Species Disease Transmission on Perceived Safety of Wild Game Meat: Building a Psychological Approach to Meat Safety

ObjectivesMeat safety is a central concern for public health. However, there is limited research on the psychological factors that influence people’s perception of meat safety. Such a psychological perspective may benefit meat science by adding understanding of how people interact with meats and how to tailor meat safety interventions to properly convey safety concerns. We will examine the psychology underlying perceptions of safety in wild game, a critical problem in global public health. Wild game provides a popular source of meat throughout the world. In equatorial regions, wild game meat is a key source of nutrients and may be the only meat sources for some rural populations. Consuming wild game is also associated with increased risk of zoonosis and has been implicated in a number of emerging diseases, including Ebola and HIV. Currently, there is limited research on how people judge the risks associated with consuming meat from wild game. According to cognitive psychology, knowing that many animals can catch a disease increases people’s beliefs that other animals are susceptible to the disease. We hypothesize that individual beliefs about the safety of eating wild game meat will associate with beliefs about the likelihood of cross-species disease transmission.Materials and MethodsParticipants (n = 210) were recruited from U.S., Australia, Canada, Great Britain, and the Bahamas using Amazon’s Mechanical Turk and completed an online survey asking them to rate the safety of wild game meat sources (mammals and birds), judge the likelihood of disease transmission between pairs of wild animals, and provide demographic information. We analyzed mean differences in perceived safety between animals and how average mammal-mammal and mammal-bird disease transmission beliefs related to perceived safety.ResultsPerceived meat safety was highest for common game (deer, rabbits, boar, and bear), and lower for less common game (squirrels, cats, dogs, raccoons, monkeys, and bats). A linear mixed effects model indicated significant variability in perceived safety across animals, F(91881) = 242.3, p < 0.001. Post hoc tests revealed significant pairwise differences in perceived safety between common and uncommon game mammals. For uncommon game, neither mammal-mammal nor mammal-bird transmission were associated with individual differences in perceived meat safety (p’s > 0.25). For common game, mammal-bird disease transmission beliefs were negatively associated with perceived meat safety, t(207) = 3.397, p < 0.001, but mammal-mammal transmission beliefs were not.ConclusionTo the extent that participants believed it was possible for common game mammals to become infected with bird diseases, they perceived mammal meat to be less safe. These results are consistent with a “premise diversity” effect from cognitive psychology and suggest that people believe diseases are more transmittable to humans via wild game meat if they are transmittable across a wide range of species. These results suggest that interventions highlighting species-to-species disease transmission risk may help to increase awareness of the dangers that wild game meat can pose to public health. Because the results were primarily limited to commonly eaten wild game, it is important for future studies to assess whether our findings generalize to safety perceptions for common livestock meat sources.

Spatial Overlap Between People and Non-human Primates in a Fragmented Landscape.

In western Uganda, the landscape surrounding Kibale National Park (KNP) contains households, trading centers, roads, fields, and forest fragments. The mosaic arrangement of these landscape features is thought to enhance human-primate interaction, leading to primate population declines and increased bi-directional disease transmission. Using a social-ecological systems research framework that captures the complexity of interaction among people, wildlife, and environment, we studied five forest fragments near KNP and conducted intensive on-the-ground mapping to identify locations of human-primate spatial overlap. Primate locations and human activities were distributed within, on the edges, and far beyond fragment borders. Analysis of shared spaces indicated that 5.5% of human space overlapped with primate spaces, while 69.5% of primate spaces overlapped with human spaces. Nearest neighbor analysis indicated that human activities were significantly spatially clustered within and around individual fragments, as were primate locations. Getis-Ord statistics revealed statistically significant "hotspots" of human activity and primate activity, but only one location where spatial overlap between humans and primates was statistically significant. Human activities associated with collecting fuelwood and other forest products were the primary drivers of human-primate overlap; however, primates also spent time outside of forest fragments in agricultural spaces. These results demonstrate that fragmented landscapes are not uniform with respect to human-primate overlap, and that the implications of human-primate interaction, such as primate population declines and possible cross-species disease transmission, are spatially aggregated.

Molecular detection of vector-borne pathogens in wild and domestic carnivores and their ticks at the human–wildlife interface

Urbanization of natural areas is considered one of the causes of the current apparent emergence of infectious diseases. Carnivores are among the species that adapt well to urban and periurban environments, facilitating cross-species disease transmission with domestic dogs and cats, and potentially with their owners. The prevalence of vector-borne pathogens (VBP) of zoonotic and veterinary interest was studied in sympatric wild and domestic carnivores into Barcelona Metropolitan Area (NE Spain). Blood or spleen samples from 130 animals, including 34 common genets (Genetta genetta), 12 red foxes (Vulpes vulpes), 10 stone martens (Martes foina), three Eurasian badgers (Meles meles), 34 free-roaming domestic cats and 37 dogs with outdoor access, were collected either in protected or adjacent residential areas. A total of 309 ticks (chiefly Rhipicephalus turanicus) were collected on these animals. The samples were analyzed with a battery of PCR assays targeting the DNA of Rickettsia spp., Anaplasmataceae, Coxiella burnetii, Bartonella spp., and Piroplasmida, and the amplicons were sequenced. The fox showed the highest prevalence (58%) and diversity of VBP (four pathogens), whereas none of the dogs were infected. Bartonella spp. (including B. clarridgeiae, B. henselae, and B. rochalimae) was the most prevalent pathogen. Infection of wild carnivores with Ehrlichia canis, C. burnetii, Theileria annae and Babesia vogeli was also confirmed, with some cases of coinfection observed. The presence of DNA of T. annae and B. vogeli was also confirmed in tick pools from four species of wild carnivores, supporting their role in piroplasmid life-cycle. By the sequencing of several target genes, DNA of Rickettsia massiliae was confirmed in 17 pools of Rh. turanicus, Rh. sanguineous, and Rh. pusillus from five different species, and Rickettsia conorii in one pool of Rh. sanguineous from a dog. None of the hosts from which these ticks were collected was infected by Rickettsia. Although carnivores may not be reservoir hosts for zoonotic Rickettsia, they can have an important role as mechanical dispersers of infected ticks.