Study of contact rates between domestic and wild ungulates in Doñana National Park

Trabajo Fin de Máster: Máster universitario en investigación básica y aplicada en recursos cinegéticos.Wild boar (Sus scrofa) is currently the most widely distributed species in overall Europe. It is also the more relevant wild reservoir of several diseases shared with livestock and/or humans, including tuberculosis (TB) that is cause by mycobacteria of Mycobaterium tuberculosis complex (MTC). The transmission of MTC is important in areas with high frequency of effective contacts between potential reservoirs, as it is the case of Doñana National Park (DNP), where domestic and wild ungulates cohabit. Different approaches have been used to determine potential contacts between individuals. In this study, using GPS-GSM tracked wild boar (n=18) and cattle (n=12), we aimed to (i) determine intra and interspecific contacts for domestic and wild ungulates; (ii) describe the seasonal contacts rates between wild boar and cattle, but also the intraspecific for wild boar; and (iii) identify the environmental variables increasing the probability of interspecific contacts occurrence. In this study, contacts were defined using two spatial (52 – 127 m) and three temporal (1 – 72 – 288 h) windows, so finally six spatio-temporal windows were used. In addition, contact presence was modelled in order to determine the environmental predictors explaining the contact pattern in DNP and its seasonality. For this purpose, random points were placed within the overlapping areas between seasonal home ranges of each pair of interacting individuals. Our results pin pointed to spring and autumn as the more relevant seasons for establishing interspecific contact. Whether these contacts involve higher potential for pathogen transmission in our study area should be addressed (for instance, less frequency of contact but occurring at localized environmental sources of pathogens may involve more risk in summer season). This study also suggests that contacts do not occur in areas with dense vegetation, as dense shrublands and woodlands but highlights the relevance of the proximity to water points and vera ecotone in explaining contacts patter in DNP. Even our results are relevant to improve the understanding of the epidemiology of TB in DNP and to support intervention measures for minimize the effective contacts between domestic and wild ungulates, a more in detail exploration of the contacts determined in our study is needed. For instance, by determining the contacting individuals, exploring the daily patterns of the contacts, and characterizing the contacts in terms of selected resources would provide better understanding of the seasonal patterns of both intraspecific and interspecific contacts.Peer Reviewe

Tuberculosis Epidemiology and Badger (Meles meles) Spatial Ecology in a Hot-Spot Area in Atlantic Spain

: We provide a temporal overview (from 2012 to 2018) of the outcomes of tuberculosis (TB) in the cattle and badger populations in a hot-spot in Asturias (Atlantic Spain). We also study the badger's spatial ecology from an epidemiological perspective in order to describe hazardous behavior in relation to TB transmission between cattle and badgers. Culture and single intradermal tuberculin test (SITT) were available for cattle as part of the National Program for the Eradication of TB. A field survey was also carried out in order to determine the paddocks and buildings used by each farm, and the information obtained was stored by using geographic information systems. Moreover, eighty-three badgers were submitted for necropsy and subsequent bacteriological studies. Ten badgers were also tracked, using global positioning system (GPS) collars. The prevalence of TB in cattle herds in the hot-spot increased from 2.2% in 2012 to 20% in 2016; it then declined to 0.0% in 2018. In contrast, the TB prevalence in badgers increased notably (from 5.55% in 2012-2015 to 10.64% in 2016-2018). Both cattle and badgers shared the same strain of Mycobacterium bovis. The collared badgers preferred paddocks used by TB-positive herds in spring and summer (when they were more active). The males occupied larger home ranges than the females (Khr95: males 149.78 ± 25.84 ha and females 73.37 ± 22.91 ha; Kcr50: males 29.83 ± 5.69 ha and females 13.59 ± 5.00 ha), and the home ranges were smaller in autumn and winter than in summer. The averages of the index of daily and maximum distances traveled by badgers were 1.88 ± (SD) 1.20 km and 1.99 ± 0.71 km, respectively. One of them presented a dispersive behavior with a maximum range of 18.3 km. The most preferred habitat was apple orchards in all seasons, with the exception of winter, in which they preferred pastures. Land uses and landscape structure, which have been linked with certain livestock-management practices, provide a scenario of great potential for badger-cattle interactions, thus enhancing the importance of the badgers' ecology, which could potentially transmit TB back to cattle in the future.This work was funded by the Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA) projects (FEDER co-funded): RTA2011-00010-00-00, RTA2014-00002-C02-01; by the Agencia Estatal de Investigación (AEI) reference project RTI2018-096010-B-C21 (FEDER co-funded); and by PCTI 2018–2020 (GRUPIN: IDI2018-000237) and FEDER. We received funds from RTI2018-096010-B-C21 (FEDER co-funded) to cover publication costs.S

Tuberculosis Epidemiology and Badger (Meles meles) Spatial Ecology in a Hot-Spot Area in Atlantic Spain

[EN] We provide a temporal overview (from 2012 to 2018) of the outcomes of tuberculosis (TB) in the cattle and badger populations in a hot-spot in Asturias (Atlantic Spain). We also study the badger’s spatial ecology from an epidemiological perspective in order to describe hazardous behavior in relation to TB transmission between cattle and badgers. Culture and single intradermal tuberculin test (SITT) were available for cattle as part of the National Program for the Eradication of TB. A field survey was also carried out in order to determine the paddocks and buildings used by each farm, and the information obtained was stored by using geographic information systems. Moreover, eighty-three badgers were submitted for necropsy and subsequent bacteriological studies. Ten badgers were also tracked, using global positioning system (GPS) collars. The prevalence of TB in cattle herds in the hot-spot increased from 2.2% in 2012 to 20% in 2016; it then declined to 0.0% in 2018. In contrast, the TB prevalence in badgers increased notably (from 5.55% in 2012–2015 to 10.64% in 2016–2018). Both cattle and badgers shared the same strain of Mycobacterium bovis. The collared badgers preferred paddocks used by TB-positive herds in spring and summer (when they were more active). The males occupied larger home ranges than the females (Khr95: males 149.78 ± 25.84 ha and females 73.37 ± 22.91 ha; Kcr50: males 29.83 ± 5.69 ha and females 13.59 ± 5.00 ha), and the home ranges were smaller in autumn and winter than in summer. The averages of the index of daily and maximum distances traveled by badgers were 1.88 ± (SD) 1.20 km and 1.99 ± 0.71 km, respectively. One of them presented a dispersive behavior with a maximum range of 18.3 km. The most preferred habitat was apple orchards in all seasons, with the exception of winter, in which they preferred pastures. Land uses and landscape structure, which have been linked with certain livestock-management practices, provide a scenario of great potential for badger–cattle interactions, thus enhancing the importance of the badgers’ ecology, which could potentially transmit TB back to cattle in the futureSIThis work was funded by the Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA) projects (FEDER co-funded): RTA2011-00010-00-00, RTA2014-00002-C02-01; by the Agencia Estatal de Investigación (AEI) reference project RTI2018-096010-B-C21 (FEDER co-funded); and by PCTI 2018–2020 (GRUPIN: IDI2018-000237) and FEDER.We received funds from RTI2018-096010-B-C21 (FEDER co-funded) to cover publication cost

The spatiotemporal dynamics of exposure of wild ungulates to Flavivirus shapes the patterns of West Nile virus outbreaks in Spain

Resumen del póster presentado a la Joint Virtual Conference of the WDA and EWDA, celebrada del 31 de agosto al 2 de septiembre de 2021.West Nile virus (WNV) is a neuropathic virus for humans, horses and birds transmitted by mosquitoes. The recent increase of clinical cases in Spain shows the need to better understand the ecology of this Flavivirus, not only in urban areas, but also where birds, WNV and mosquitoes interact with wild ungulates, to better predict/prevent WNV outbreaks. We analysed the dynamics of exposure of wild ungulates to Flavivirus along 15 years (2005-2019) in a south-to-north gradient in 5 areas where WNV cases occur since 2007. Sera of 2,418 wild ungulates (Cervus elaphus &Sus scrofa) from Doñana National Park (A1), Western Sierra Morena (A2), Central Sierra Morena (A3), Guadiana river Valley (A4) and Toledo Mounts (A5) were analysed with a blocking ELISA highly specific for WNV. Weather conditions were gathered from two climatically and environmentally contrasting areas: i) A1, a thermo-Mediterranean wetland; and ii) A4, a Mediterranean continental forest/shrubland. The risk of Flavivirus exposure of ungulates was modelled with weather covariates (average winter/spring/summer temperatures and annual/winter-spring/spring/summer rainfall) by logistic binary regression. The proportion of exposed ungulates was higher in A1 (33.5%) and A2 (35.3%) than in A3 (18.7%), A4 (20.3%) and A5 (18.7%), shaping the contrasting reported incidence of WNV outbreaks in southern (n=189) and south-central (n=2) Spain. The annual patterns of exposure of ungulates also shaped the temporal emergence of WNV outbreaks. Higher winter temperature associated positively to the risk of exposure in A1 whereas in A4 the risk increased with annual rainfall whereas it decreased with increasing spring precipitation. These preliminary results point out that whereas in wetlands, where water is abundant, smoother winter temperatures better predict WNV circulation, annual rainfall seems to be a better predictor for WNV infection risk in dry continental Mediterranean areas. Wild ungulates additionally prove to be efficient predictors for Flavivirus spatiotemporal dynamics.Peer reviewe

Tendance temporelle de la tuberculose dans la communauté d’ongulés du Parc National de Doñana

Trabajo presentado al 35º Encuentro GEEFSM (Groupe d’Etudes sur l’Eco-pathologie de la Faune Sauvage de Montagne), celebrado en Cofrentes, Muela de Cortes (España) del 1 al 4 de junio de 2017.[ES]: El control de las enfermedades infecciosas compartidas entre la fauna silvestre y el ganado es complejo debido al escaso conocimiento de los procesos epidemiológicos que determinan la transmisión y persistencia de patógenos en la comunidad de hospedadores. La tuberculosis animal (TB) causada por la infección crónica del Complejo Mycobacterium tuberculosis (CMT) es endémica en jabalí (Sus scrofa), ciervo (Cervus elaphus) y gamo (Dama dama) en el centro-sur de España. En este contexto es clave conocer la dinámica temporal de la infección y los factores que modulan el mantenimiento de la TB en el medio natural y, consecuentemente, en el ganado en extensivo. Así, en este estudio utilizamos datos de seguimiento sanitario de ungulados silvestres y de bovino del Parque Nacional de Doñana (PND) para evaluar la tendencia temporal en la prevalencia de TB e identificar sus determinantes. Entre 2006 y 2016 se ha realizado la necropsia, el diagnóstico clínico- lesional y confirmación por cultivo microbiológico en un total de 852 jabalíes, 356 ciervos y 338 gamos dentro del plan de vigilancia sanitaria del PND. Por otro lado, la información sanitaria de 1139 cabezas de ganado bovino ha sido facilitada por los servicios veterinarios oficiales. El análisis espacio-temporal de la infección y sus principales factores de riesgo se ha realizado usando sistemas de información geográfica y modelos lineales generalizados. Los resultados muestran prevalencias de TB más elevadas en jabalí (69,44%), seguido de ciervo (43,38%) y gamo (19,88%); mientras que la incidencia en bovino es del 9%. La tendencia temporal de la infección durante el período estudiado es creciente en ungulados silvestres y se mantiene estable en el ganado bovino, a pesar de los intensos esfuerzos de erradicación en esta especie. En general, varios factores individuales, poblacionales, climatológicos y geográficos están involucrados en la dinámica de la enfermedad. Los individuos adultos muestran una prevalencia elevada respecto a los jóvenes en todas las especies, como se ha sugerido previamente en enfermedades de carácter crónico. En cuanto a la distribución espacial de la infección, se mantiene un marcado gradiente Norte- Sur descrito previamente en 2008, observándose valores superiores de prevalencia en aquellas áreas situadas al norte del PND. Esta situación podría estar mediada por las diferencias en la densidad de hospedadores y en el uso de los recursos. Por ejemplo, se aprecia un mayor riesgo relativo de TB en la cercanía a zonas de elevada agregación de individuos, como es el húmedo borde de la marisma. Estos resultados sobre la dinámica de la TB son fundamentales para comprender la epidemiología de la enfermedad en la comunidad de hospedadores y permitirán ayudar en el diseño de futuras estrategias de control.[IT]: Il controllo delle malattie infettive condivise tra la fauna selvatica e il bestiame è complesso a causa della scarsa conoscenza dei processi epidemiologici che determinano la trasmissione e la persistenza dei patogeni nella comunità di animali ospiti. La tubercolosi animale (TB) causata dall’infezione cronica da parte del Complesso Mycobacterium tuberculosis (CMT) è endemica nel cinghiale (Sus scrofa), cervo (Cervus elaphus) e daino (Dama dama) nel centro- sud della Spagna. In questo contesto è essenziale conoscere la dinamica temporale dell’infezione e i fattori che modulano il mantenimento della TB nell’ambiente naturale e, di conseguenza, nell’allevamento estensivo. In questo studio vengono utilizzati dati di controllo sanitario di ungulati silvestri e bovini nel Parco Nazionale della Dognana (PND), per valutare l’evoluzione temporale nella prevalenza della TB e identificarne i fattori determinanti. Tra il 2006 e il 2016 sono stati realizzati necroscopia, diagnosi clinico-lesionale e conferma tramite coltura microbiologica su un totale di 852 cinghiali, 356 cervi e 338 daini nell’ambito del piano di vigilanza sanitaria del PND. Le informazioni relative a 1139 teste di bestiame (bovino) sono state fornite invece dai servizi sanitari veterinari ufficiali. L’analisi spazio-temporale dell’infezione e dei suoi principali fattori di rischio è stata realizzata utilizzando sistemi di informazione geografica e modelli lineari generalizzati. I risultati mostrano prevalenza di TB più alta nelcinghiale (69,44%), seguito da cervo (43,38%) e daino (19,88%), mentre l’incidenza nel bestiame è del 9%. Durante il periodo studiato l’infezione è andata aumentando negli ungulati selvatici e si è mantenuta stabile nel bestiame, nonostante gli intensi sforzi di eradicazione in questa specie. In generale, vari fattori individuali, demografici, climatologici e geografici sono coinvolti nella dinamica della malattia. Gli individui adulti mostrano una prevalenza più elevata rispetto ai giovani in tutte le specie, come si era già visto precedentemente in altre malattie a carattere cronico. In quanto alla distribuzione spaziale dell’infezione, si mantiene una marcata prevalenza a nord rispetto al sud, già descritta prima nel risultando valori superiori nelle aree situate al nord del PND. Questa situazione potrebbe essere dovuta alle differenze di densità demografica degli ospiti e nell’uso condiviso delle risorse. Per esempio, è stato riscontrato un maggiore rischio relativo di TB nella vicinanza di zone con un alto indice di aggregazione degli individui, come ad esempio i terreni paludosi. Questi risultati sulla dinamica della TB sono fondamentali per comprendere l’epidemiologia della malattia nella comunità degli animali che ne sono ospiti e permetteranno lo sviluppo di future strategie di controllo.[FR]: Le contrôle des maladies infectieuses communes à la faune sauvage et à l’élevage est complexe dû aux faibles connaissances des processus épidémiologiques qui déterminent la transmission et la persistance des pathogènes dans la population d’hôtes. La tuberculose animale (TB) causée par l’infection chronique du Complejo Mycobacterium tuberculosis (CMT) est endémique chez le sanglier (Sus scrofa), le cerf (Cervus elaphus) et le daim (Dama dama) dans le centre-sud de l’Espagne. Dans ce contexte, il est primordial de connaître la dynamique temporelle de l’infection et les facteurs qui modulent le maintien de la TB dans le milieu naturel et, par conséquent, dans l’élevage extensif. Ainsi, dans cette étude, nous utilisons des données de suivi sanitaire des ongulés sauvages et des bovins du Parc National de Doñana (PND) pour évaluer la tendance temporelle dans la prévalence de TB et identifier ses déterminants. Entre 2006 et 2016, il a été réalisé l’autopsie, le diagnostic clinique et la confirmation par culture microbiologique sur un total de 852 sangliers, 356 cerfs et 338 daims dans le plan de vigilance sanitaire du PND. D’autre part, l’information sanitaire de 1139 têtes de bovins a été apportée par les services vétérinaires officiels. L’analyse spatio-temporelle de l’infection et ses principaux facteurs de risque a été réalisée en utilisant ses systèmes d’information géographique et des modèles linéaux généraux. Les résultats indiquent des prévalences de TB plus élevées chez le sanglier (69,44%), suivi du cerf (43,38%) et du daim (19,88%) ; alors que l’incidence chez les bovins es de 9%. La tendance temporelle de l’infection durant la période étudiée est croissante chez les ongulés sauvages et reste stable chez les bovins domestiques, malgré les efforts intenses d’éradication dans cette espèce. En général, plusieurs facteurs individuels, de groupes, climatologiques et géographiques sont impliqués dans la dynamique de la maladie. Les individus adultes présentent une prévalence élevée par rapport aux jeunes et ce dans toutes les espèces, ce qui est généralement le cas pour beaucoup de maladies chroniques. Par rapport à la distribution spatiale de l’infection, elle est surtout située dans le Nord-Sud, comme il a été décrit précédemment en 2008, où des valeurs supérieures de prévalence ont été observées dans les aires situées au nord du PND. Cette situation pourrait être due aux différences dans la densité des hôtes et dans l’utilisation des ressources. Par exemple, on observe un risque plus grand de TB à proximité des zones de densité élevée d’individus, comme le bord humide des marais. Ces résultats sur la dynamique de la TB sont fondamentaux pour comprendre l’épidémiologie de la maladie dans la communauté d’hôte et permettent d’aider pour le développement de futures stratégies de contrôle.Peer reviewe

The spatiotemporal dynamics of Crimean-Congo haemorrhagic fever virus in enzootic Iberian scenarios

Resumen del trabajo presentado a la Joint Virtual Conference of the WDA and EWDA, celebrada del 31 de agosto al 2 de septiembre de 2021.Peer reviewe

Estudio de la interacción entre el ganado doméstico y la fauna silvestre como información básica para el control de enfermedades compartidas

Resumen del trabajo presentado a las V Jornadas Doctorales de la Universidad de Castilla-La Mancha, celebradas en Ciudad Real (España) el 6 de octubre de 2015.En el centro y sur de España (CSE) la presencia de ganado en extensivo está en muchas situaciones asociada a los ungulados silvestres con los cuales puede compartir enfermedades. En estas áreas se generan situaciones epidemiológicas complejas, que no sólo se encuentran reguladas por el manejo del ganado, sino también por la ecología y comportamiento de los silvestres. Así, la existencia de reservorios silvestres de enfermedades tiene una elevada relevancia socioeconómica para el sector agroalimentario, ya que en muchos casos hacen infructuosos los esfuerzos dedicados a la erradicación/control de enfermedades en el ganado. En este contexto, el conocimiento de los aspectos relacionados con el uso del espacio del ganado y la fauna, y de sus áreas de interacción en relación al ambiente se muestra fundamental para el control de enfermedades en la interfase entre la fauna silvestre y el ganado en extensivo. Pese a que en la última década diferentes investigaciones han avanzado en el estudio de la interacción epidemiológica entre silvestres y domésticos, únicamente en los últimos años se está abordando el control de las enfermedades compartidas de una forma aplicada. [Objetivos]: El conocimiento y correcto manejo de las interacciones inter e intraespecíficas puede contribuir a disminuir la trasmisión de enfermedades infecciosas en tales zonas de contacto. Así, el objetivo general de esta tesis es describir los riesgos de transmisión de enfermedades entre el ganado extensivo y los ungulados silvestres como información básica para el control de enfermedades en sistemas epidemiológicos complejos. Se pueden destacar tres objetivos concretos: i) Estudiar los patrones espaciales de agregación de fauna silvestre y doméstica mediante el seguimiento via GPS-GSM (con sensor de proximidad) de individuos. i.1) Identificar los contactos intra e interespecíficos y su temporalidad. i.2) Determinar los factores de riesgo que explican el patrón de contactos. ii) Analizar y caracterizar la red de contactos entre individuos por medio del análisis de redes neuronales y los factores de riesgo que las determinan a nivel individual y poblacional. Estos objetivos permitirán identificar los factores más importantes que modulan los patrones de interacción entre silvestres y domésticos, lo que supondrá información básica para el diseño de programas de control biosanitario de enfermedades compartidas, minimizando las interacciones infectivas entre el ganado y la fauna silvestre.Peer reviewe

Performance of proximity loggers under controlled field conditions: an assessment from a wildlife ecological and epidemiological perspective

[Background]: Ecological sciences have, in recent decades, benefited from the ability of proximity loggers (PLs)—i.e. devices that transmit and receive radio signals (UHF)—to quantify intra- and inter-specific interactions. These are used to estimate the frequency of contacts according to a predefined distance between individuals or between individuals and environmental features. The performance of these devices may, however, be potentially affected by several factors, signifying that they require accurate calibration under field conditions in order to correctly interpret the information obtained. We assessed the effect of four relevant factors in ecological and epidemiological studies over the attenuation of radio waves in terms of the received signal strength indicator (RSSI) and contact success rate at a short (3 m) and medium distance (up to 20 m). The factors considered were: height above the ground (0–1 m), the presence/absence of vegetation, the presence/absence of live body mass around the devices, the distance between devices and the overlaid effects of all of them.[Results]: The RSSI was found to be an accurate measure of distance, although its precision decreased over greater distances (up to 100 m), with the loss being sharper with vegetation, with body mass and when the devices were located on the ground. The success rate at up to 20 m decreased with distance and was also affected by body mass and vegetation. A probability of contact success of 81% was obtained in the best conditions (without vegetation and body mass) at a distance of 3 m, whereas it was of 56% in the worst conditions.[Conclusions]: Our study shows the potential synergistic effects of external factors on the performance of PLs, even when they are used to infer near-contacts. We, therefore, highlight the importance of assessing, for each particular study, the combined effect of non-controllable external factors on the performance of PLs in order to estimate the minimum (best scenario) and maximum (worst scenario) level of underestimation in the field data. The sampling design described here is a cost-effective protocol suitable for this purpose.The present work has benefitted from the financial aid of a research Grant funded by MINECO (AGL2013-48523-C3-1-R and AGL2016-76358-R). RTO holds a pre-doctoral scholarship from UCLM. PA is supported by MINECO-UCLM through a “Ramón y Cajal” contract (RYC-2012-11970).Peer reviewe

Dynamic Network of Interactions in the Wildlife-Livestock Interface in Mediterranean Spain: An Epidemiological Point of View

The correct management of diseases that are transmitted between wildlife and livestock requires a reliable estimate of the pathogen transmission rate. The calculation of this parameter is a challenge for epidemiologists, since transmission can occur through multiple pathways. The social network analysis is a widely used tool in epidemiology due to its capacity to identify individuals and communities with relevant roles for pathogen transmission. In the present work, we studied the dynamic network of interactions in a complex epidemiological scenario using information from different methodologies. In 2015, nine red deer, seven fallow deer, six wild boar and nine cattle were simultaneously monitored using GPS-GSM-Proximity collars in Doñana National Park. In addition, 16 proximity loggers were set in aggregation points. Using the social network analysis, we studied the dynamic network of interactions, including direct and indirect interactions, between individuals of different species and the potential transmission of pathogens within this network. The results show a high connection between species through indirect interactions, with a marked seasonality in the conformation of new interactions. Within the network, we differentiated four communities that included individuals of all the species. Regarding the transmission of pathogens, we observed the important role that fallow deer could be playing in the maintenance and transmission of pathogens to livestock. The present work shows the need to consider different types of methodologies in order to understand the complete functioning of the network of interactions at the wildlife/livestock interface. It also provides a methodological approach applicable to the management of shared diseases