Eliminating Rabies in Estonia

The compulsory vaccination of pets, the recommended vaccination of farm animals in grazing areas and the extermination of stray animals did not succeed in eliminating rabies in Estonia because the virus was maintained in two main wildlife reservoirs, foxes and raccoon dogs. These two species became a priority target therefore in order to control rabies. Supported by the European Community, successive oral vaccination (OV) campaigns were conducted twice a year using Rabigen® SAG2 baits, beginning in autumn 2005 in North Estonia. They were then extended to the whole territory from spring 2006. Following the vaccination campaigns, the incidence of rabies cases dramatically decreased, with 266 cases in 2005, 114 in 2006, four in 2007 and three in 2008. Since March 2008, no rabies cases have been detected in Estonia other than three cases reported in summer 2009 and one case in January 2011, all in areas close to the South-Eastern border with Russia. The bait uptake was satisfactory, with tetracycline positivity rates ranging from 85% to 93% in foxes and from 82% to 88% in raccoon dogs. Immunisation rates evaluated by ELISA ranged from 34% to 55% in foxes and from 38% to 55% in raccoon dogs. The rabies situation in Estonia was compared to that of the other two Baltic States, Latvia and Lithuania. Despite regular OV campaigns conducted throughout their territory since 2006, and an improvement in the epidemiological situation, rabies has still not been eradicated in these countries. An analysis of the number of baits distributed and the funding allocated by the European Commission showed that the strategy for rabies control is more cost-effective in Estonia than in Latvia and Lithuania

Étude de la transmission d'Echinococcus multilocularis dans une grande agglomération : influence du comportement alimentaire et de l'utilisation de l'espace par le renard roux (Vulpes vulpes) sur la contamination de l'environnement.

Alveolar Echinococcosis is a lethal zoonosis transmitted to humans by the ingestion of eggs of the tænia Echinococcus multilocularis. The cycle of the parasite needs a carnivore as definitive host (mainly the red fox) and the common and water voles (Microtus arvalis and Arvicola terrestris) as intermediate hosts. Since 20 years, the more and more common observations of urban foxes gave rise to many questions about the possible increased risk of transmission to man due to the proximity of foxes. Recent studies showed the presence of E. multilocularis in urban foxes with variable prevalence. However, the conditions of the development of this parasite in the urbanized area are few documented. Work presented here proposes to improve comprehension of the cycle of E. multilocularis in such urbanized area. A monitoring of the red fox infection by collection of road kills or trapped animals highlighted a "rural to urban" decreasing gradient of infection. Along this gradient, different habitats were regularly sampled; this study showed the importance for the red fox of the availability of Microtus sp. in waste land landscape. The study of the adaptation of its diet by red fox to the variations of rodents densities showed that the Microtus sp. was highly consumed even when it was poorly represented in the field whereas in peri-urban area, A. terrestris,is consumed according to its availability. Taking in account the availability of rodents on the scale of the city, it was shown that the consumption of intermediate hosts is more important in rural area than in urban area and that the rural diet exhibits a predominance of Microtus sp. versus A. terrestris whereas these differences are lacking in urban area. The distribution of faeces of the red fox appeared correlated with the densities of Microtus sp and A. terrestris, underlining the possibilities of closing the parasitic cycle whatever the urbanization level. Lastly, the study of foxes movements using GPS collars has allowed to observe various types of behaviours which could induce a modulation in the space dynamics of the urban transmission of the parasite based on the stability of the local red fox populations.L'Echinococcose Alveolaire est une zoonose mortelle transmise a l'Homme par l'ingestion des oeufs du tænia Echinococcus multilocularis. Le cycle du parasite fait intervenir un carnivore comme hote definitif (principalement le renard roux) et des campagnols prairiaux (Microtus arvalis et Arvicola terrestris) comme hotes intermediaires. Depuis une vingtaine d'annees, les observations de plus en plus frequentes de renards urbains ont suscite de nombreuses questions sur l'augmentation du risque de contamination humaine a cause de cette proximite des renards. Des etudes recentes ont montre la presence d'E. multilocularis chez le renard urbain avec des prevalences tres variables. Cependant, les conditions du developpement de ce parasite dans les milieux urbanises sont peu documentees. Les travaux presentes proposent d'ameliorer la comprehension du cycle d'E. multilocularis dans de tels milieux. Un suivi de l'infection vulpine par collecte de cadavres a mis en evidence un gradient d'infection decroissant du milieu rural au milieu urbain. Le long de ce gradient, differents milieux ont ete regulierement echantillonnes et ont montre l'importance pour le renard roux de la disponibilite en Microtus sp. dans les milieux friches. L'etude de la reponse alimentaire du renard roux aux variations de densites de rongeurs a montre que Microtus sp. etait fortement consomme meme lorsqu'il etait faiblement present sur le terrain alors que A. terrestris, en milieu peri-urbain, est consomme selon sa disponibilite. L'etude de la disponibilite en rongeurs a l'echelle de la ville montre que la consommation en hotes intermediaires est plus importante en milieu rural qu'en milieu urbain et que le regime alimentaire rural se caracterise par une predominance de Microtus sp. par rapport a A. terrestris alors que ces differences sont pas presentes en milieu urbain. La repartition des feces de renard roux est correlee aux densites de Microtus sp et d'A. terrestris, soulignant les possibilites d'existence du cycle parasitaire quel que soit le niveau d'urbanisation. Enfin, l'etude de trajectoires de renards par utilisation de colliers GPS a permis d'observer differents types de comportements individuels qui pourraient entrainer une modulation de la dynamique spatiale de la transmission urbaine du parasite basee sur la stabilite des populations vulpines

Mapping Habitats by Integrating Multi-Source Land Use Land Cover Databases: Application to Red Fox in Urban Area

Conference GISTAM 2024, 2-4 april 2024, Angers (France)International audienceHabitats are key components for understanding wildlife space use. Having access to an accurate description of habitats can contribute to conservation programs and help define optimal landscape planning projects. In this study, we focus on the study case of red fox in a French urban environment. Our approach was to describe and to map habitats at a detailed spatial scale based on existing and available multi-source geographical databases. An automatic mapping process was proposed and then applied on the study site. The computed map was assessed based on a ground truth: depending on the land covers, the precision was good, between 69% and 94%. A GPS location dataset of red fox individuals were analysed with respect to the proposed map. Results showed consistent space use between the GPS locations and literature. They highlighted that separating land cover from land use is beneficial to consider the influence on red fox of both landscape features and their anthropic uses. The opportunit y of the proposed automatic process is to be able to map habitats regarding the ecological functions of the landscape, in various environments and at different dates

Editing maps of landscape elements according to their potential influence on animals by combining multi-source data: a case study about red foxes in urban environment

International audienceWildlife present in urban environments uses the space as shaped by human infrastructures and activities (Jokimäki et al., 2011). Landscape planning has to take into account animals’ space use so that to enable good ecological functioning and to identify places of interface between wildlife and human, particularly relevant in the management of zoonosis (Plumer et al., 2014). Meeting this need remains a challenge due to the scarcity of animals’ data and their dependency on specific collect contexts (the observed animal, its personality, the area, recording parameters).Our study case deals with red fox (Vulpes vulpes) in the city of Nancy in eastern France. Our aim is to propose a map of landscape elements that would be selected according to their potential influence on the species’ space use (Burel et al., 1999). This influence may be attractiveness for the presence of animals, or avoidance. It may also correspond to corridors or obstacles to movements.The edition of such map implied integrating multi-theme and multi-source geographical data, about physical landscape description, human activities, animals’ locations, and from institutional databases, crowd-sourcing, local expert studies and ad-hoc data collections (Zhang et al., 2019). The targeted integration result was a set of geometrical parcels characterized into two distinct classifications on land cover types and human land uses. Labels in the classifications were defined relying on the analysis of red foxes’ GPS locations (Robardet, 2007) which highlighted specific landscape elements to consider (vegetation patches, railways, property boundaries which might be fences, walls) and temporalities related to daytime and night time and to individual rhythms.Validation is based on a comparison between the resulted map and reference data based on field survey and visual interpretation of images. The map stands as a display of the space interpreted with a landscape planning objective and requiring regular updating