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Background: Culicoides biting midges transmit viruses resulting in disease in ruminants and equids such as bluetongue, Schmallenberg disease and African horse sickness. In the past decades, these diseases have led to important economic losses for farmers in Europe. Vector abundance is a key factor in determining the risk of vector-borne disease spread and it is, therefore, important to predict the abundance of Culicoides species involved in the transmission of these pathogens. The objectives of this study were to model and map the monthly abundances of Culicoides in Europe. Methods: We obtained entomological data from 904 farms in nine European countries (Spain, France, Germany, Switzerland, Austria, Poland, Denmark, Sweden and Norway) from 2007 to 2013. Using environmental and climatic predictors from satellite imagery and the machine learning technique Random Forests, we predicted the monthly average abundance at a 1 km2 resolution. We used independent test sets for validation and to assess model performance. Results: The predictive power of the resulting models varied according to month and the Culicoides species/ensembles predicted. Model performance was lower for winter months. Performance was higher for the Obsoletus ensemble, followed by the Pulicaris ensemble, while the model for Culicoides imicola showed a poor performance. Distribution and abundance patterns corresponded well with the known distributions in Europe. The Random Forests model approach was able to distinguish differences in abundance between countries but was not able to predict vector abundance at individual farm level. Conclusions: The models and maps presented here represent an initial attempt to capture large scale geographical and temporal variations in Culicoides abundance. The models are a first step towards producing abundance inputs for R0 modelling of Culicoides-borne infections at a continental scale. [ABSTRACT FROM AUTHOR]

Simple Summary: African swine fever (ASF) is a viral haemorrhagic pig disease that continues to spread in Europe and severely damages pig production and economy, disrupts trade with pigs and porcine products and even has an impact on social welfare in affected areas. Wild boar and domestic pigs are both susceptible to infection with the ASF virus, which causes generalised haemorrhagic illness, fever and rapid death of most infected animals within a few days. ASF occurrence in wild boar dominates the spread and persistence of this disease in Europe and poses an imminent threat for spill-over infections with ASFV in domestic pig holdings. Wild boar represent an intelligent and adaptable wildlife host for ASF with an expansive distribution range in Europe and complex biology. Wild boar thus intricately link ASF with their habitat, making ASF inherently complicated and resource-hungry to control in the environment. This work reviews the currently known environmental risk factors for ASF in wild boar and specifically assesses the role that climate, land cover, human activity, wild boar and disease distribution play in the occurrence of ASF in wild boar. The reviewed risk information guides the implementation of ASF control measures in wild boar. A detailed understanding of environmental risk factors for African swine fever (ASF) in wild boar will be not only essential for risk assessments but also for timely and spatially informed allocation of resources in order to manage wild boar-targeted ASF control measures efficiently. Here, we review currently known environmental risk factors that can influence the occurrence of ASF virus infection in wild boar when compared to disease occurrence in wild boar of a non-exposed reference scenario. Accordingly, the exposure of wild boar to environmental risk factors related to (1) climate, (2) land cover, (3) human activity, (4) wild boar and (5) ASF were evaluated. As key environmental risk factors in this review, increased ASF occurrence in wild boar was associated with seasonal patterns, forest coverage, presence of water, human presence, farming activities, wild boar density and ASF nearness. The review highlights inconsistencies in some of these risk factor associations with disease detection in space and time and may provide valuable insights for the investigation of ASF transmission dynamics. The examined risk information was applied to consider potential improvements of the ASF control strategy in wild boar regarding disease surveillance, hunting, wild boar carcass searches and ASF barrier implementation. [ABSTRACT FROM AUTHOR]

Abstract: In late 2008, bluetongue virus (BTV) serotype 6 (BTV-6), which had never occurred in Europe before, was first detected in the Netherlands and Germany. While the origin of the virus remains unknown, the prevalence of infections in cattle was investigated in a virological (N =28,658) and serological (N =2075) field survey in Lower Saxony, where 45 cases confined to the district Grafschaft Bentheim were found. Blood from affected animals was used for the experimental infection of three cattle with different BTV antibody status, leading to sustained viraemia in one animal naïve for BTV. Of two animals that had detectable antibodies against BTV serotype 8, one became transiently infected and seroconverted for BTV-6 while the other did not react. In conclusion, while only a very limited spread of BTV-6 could be observed in the field, experimental infection of cattle did not show substantial differences of the course of infection in comparison to other BTV serotypes. [Copyright &y& Elsevier]

The introduction of genotype II African swine fever (ASF) virus, presumably from Africa into Georgia in 2007, and its continuous spread through Europe and Asia as a panzootic disease of suids, continues to have a huge socio-economic impact. ASF is characterized by hemorrhagic fever leading to a high case/fatality ratio in pigs. In Europe, wild boar are especially affected. This review summarizes the currently available knowledge on ASF in wild boar in Europe. The current ASF panzootic is characterized by self-sustaining cycles of infection in the wild boar population. Spill-over and spill-back events occur from wild boar to domestic pigs and vice versa. The social structure of wild boar populations and the spatial behavior of the animals, a variety of ASF virus (ASFV) transmission mechanisms and persistence in the environment complicate the modeling of the disease. Control measures focus on the detection and removal of wild boar carcasses, in which ASFV can remain infectious for months. Further measures include the reduction in wild boar density and the limitation of wild boar movements through fences. Using these measures, the Czech Republic and Belgium succeeded in eliminating ASF in their territories, while the disease spread in others. So far, no vaccine is available to protect wild boar or domestic pigs reliably against ASF.

Background: Toxoplasma gondii infections and cases of clinical toxoplasmosis have been recorded in zoo animals. Wild felids in human care can serve as definitive hosts that shed oocysts, but also as intermediate hosts for the parasite. Some felid species, such as the Pallas's cat (Otocolobus manul) or sand cat (Felis margarita), may suffer from clinically apparent toxoplasmosis. In the present study, our main aim was to assess risk factors for T. gondii infections in small exotic felids., Methods: A seroepidemiological study was conducted using the reduviid bug Dipetalogaster maxima for blood sample collection, a method previously evaluated on domestic cats. A total of 336 samples from 17 felid species were collected in 51 institutions, 48 of which were within Europe and the remaining three in the Middle East (United Arabic Emirates and Qatar). These samples were analyzed for T. gondii antibodies by immunoblotting and an immunofluorescent antibody test. Potential risk factors in zoos for seropositivity regarding T. gondii among members of the European Association of Zoos and Aquaria (EAZA) were evaluated using a questionnaire and individual data from the Zoological Information Management System (ZIMS)., Results: The sampled felids showed an overall seroprevalence for T. gondii of 63%. The risk factor study including data of 311 small exotic cats of 10 species resulted in a final generalized linear mixed model comprised of five variables: the likelihood of seropositivity increased statistically significantly with "Age", while feeding "Cattle: frozen" relative to "Cattle: fresh", "Outdoor housing fenced in on all sides", "Mesh size 2-5 cm" relative to "Mesh size > 5 cm" and "Wearing gloves: yes" had statistically significant protective effects., Conclusions: Wild felids, including endangered species, kept in human care in European and Middle Eastern institutions, are widely exposed to T. gondii. Risk factor analysis revealed that feeding previously frozen tissues, keeping animals in enclosures that are fenced on all sides using fences with small mesh sizes, and wearing gloves when working inside enclosures seem to be the most relevant protective measures to prevent T. gondii infections in these animals .

Background: The need for wildlife health surveillance as part of disease control in wildlife, domestic animals and humans on the global level is widely recognized. However, the objectives, methods and intensity of existing wildlife health surveillance programs vary greatly among European countries, resulting in a patchwork of data that are difficult to merge and compare. This survey aimed at evaluating the need and potential for data harmonization in wildlife health in Europe. The specific objective was to collect information on methods currently used to estimate host abundance and pathogen prevalence. Questionnaires were designed to gather detailed information for three host-pathogen combinations: (1) wild boar and Aujeszky's disease virus, (2) red fox and Echinococcus multilocularis, and (3) common vole and Francisella tularensis., Results: We received a total of 70 responses from 19 European countries. Regarding host abundance, hunting bags are currently the most widely accessible data source for widely distributed mid-sized and larger mammals such as red fox and wild boar, but we observed large differences in hunting strategies among countries as well as among different regions within countries. For small rodents, trapping is the method of choice, but practical applications vary among study sites. Laboratory procedures are already largely harmonized but information on the sampled animals is not systematically collected., Conclusions: The answers revealed that a large amount of information is available for the selected host-pathogen pairs and that in theory methods are already largely harmonized. However, the comparability of the data remains strongly compromised by local differences in the way, the methods are applied in practice. While these issues may easily be overcome for prevalence estimation, there is an urgent need to develop tools for the routine collection of host abundance data in a harmonized way. Wildlife health experts are encouraged to apply the harmonized APHAEA protocols in epidemiological studies in wildlife and to increase cooperation.

Alveolar echinococcosis (AE), caused by the larval (metacestode) stage of Echinococcus multilocularis, is considered one of the most serious parasitic zoonoses in Central and Eastern Europe and is emerging also in large parts of Asia and in North America. The red fox represents the main definitive host of E. multilocularis in Europe, but the raccoon dog, the domestic dog and to a much lesser extent the domestic cat also represent potential definitive hosts. The natural intermediate hosts of E. multilocularis are mainly voles. The spectrum of accidental hosts is broad and includes many species of monkeys, pigs, dogs and humans which get infected by oral uptake of the viable eggs. Yet, human AE is a very rare disease in Europe; incidences have increased in recent years, while the infection is widely distributed in foxes with high prevalences reaching up to 70% in some areas. Generally, infected foxes represent a zoonotic risk, which may be particularly relevant in urban areas. Furthermore, there is concern that the risk for humans to acquire AE may rise due to the suspected geographical spread of the parasite as assessed by infections in its definitive hosts and the high prevalences in some regions. Monitoring and surveillance activities have therefore been initiated in a few European countries. Several diagnostic strategies have been developed and validated in recent years, applying classical worm detection by microscopy, but also immunological (ELISA for coproantigen detection) and molecular tests (copro-DNA detection by PCR). However, there is an urgent need for defining minimal requirements and harmonised approaches for these activities to allow for a reliable assessment of the epidemiological situation in Europe and comparable results from different countries., (Copyright © 2015. Published by Elsevier B.V.)

In autumn 2011, a novel species of the genus Orthobunyavirus of the Simbu serogroup was discovered close to the German/Dutch border and named Schmallenberg virus (SBV). Since then, SBV has caused a large epidemic in European livestock. Like other viruses of the Simbu serogroup, SBV is transmitted by insect vectors. Adult ruminants may show a mild transient disease, while an infection during a critical period of pregnancy can lead to severe congenital malformation, premature birth or stillbirth. The current knowledge about the virus, its diagnosis, the spread of the epidemic, the impact and the possibilities for preventing infections with SBV is described and discussed., (Copyright © 2014 Elsevier B.V. All rights reserved.)

During the Schmallenberg virus (SBV) epidemic, the European Food Safety Authority (EFSA) collected data on SBV occurrence across Europe in order to provide an assessment of spread and impact. By May 2013, twenty-nine countries were reporting to EFSA and twenty-two countries had reported cases of SBV. The total number of SBV herds reported was 13,846 and the number of SBV laboratory confirmed herds was 8730. The surveillance activities were based on the detection of SBV clinical cases (either adults or newborns). Malformation in newborns was the most commonly reported clinical sign of SBV-infection. All countries were able to provide the date when the first suspicion of SBV in the herd was reported and nineteen could report the location of the herd at a regional level. This allowed the spread of SBV in Europe to be measured both temporally and spatially. The number of SBV confirmed herds started to increase in December 2011 and two peaks were observed in 2012 (February and May). Confirmed herds continued to be reported in 2012 and into 2013. An increase during winter 2012 and spring 2013 was again observed, but the number of confirmed herds was lower than in the previous year. SBV spread rapidly throughout Europe from the initial area of detection. SBV was detected above the latitude of 60° North, which exceeds the northern expansion observed during the bluetongue virus serotype 8 epidemic in 2006-2009. The impact of SBV was calculated as ratio of the number of herds with at least one malformed SBV positive foetus and the total number of herds in this region. The 75th percentile of the malformations ratio in the various affected countries for the whole reporting period was below 1% and 3% for cattle and sheep herds, respectively. International data collection on emerging diseases represents a challenge as the nature of available data, data quality and the proportion of reported cases may vary widely between affected countries. Surveillance activities on emerging animal diseases are often structured only for case detection making the estimation of infection/diseases prevalence and the investigation of risk factors difficult. The impact of the disease must be determined to allow risk managers to take appropriate decisions. Simple within-herd impact indicators suitable for emerging disease outbreaks should be defined that could be measured as part of routine animal health surveillance programmes and allow for rapid and reliable impact assessment of emerging animal health diseases., (Copyright © 2014 Elsevier B.V. All rights reserved.)

A total of 26,220 foxes that were hunted or found dead in Thuringia, Germany, between 1990 and 2009 were examined for infection with Echinococcus multilocularis, the causative agent of human alveolar echinococcosis, and 6853 animals were found infected. The available data on the foxes including the location (local community; district) and the date of hunting/death were analyzed using a hierarchical Bayesian space-time model. The distribution of the model parameters and their variability was estimated on the basis of the sample size, the number of cases per spatial unit and time interval, and an adjacency matrix of the municipalities using a Markov Chain Monte Carlo simulation technique to assess the spatial and temporal changes in the distribution of the parasite. The model used to evaluate the data is widely applicable and can be applied to analyse data sets with gaps and variable sample sizes per spatial and temporal unit. In the study area, the prevalence of E. multilocularis increased from 11.9% (95% confidence interval 9.9-14.0%) in 1990 to 42.0% (39.1-44.1%) in 2005. While the infection was present in foxes only in the north-western parts of Thuringia in 1990, it had spread over the entire state by 2004. These results demand increased vigilance for human alveolar echinococcosis in Thuringia., (Copyright © 2011 Elsevier B.V. All rights reserved.)

In the summer of 2006, a bluetongue epidemic started in the border area of Belgium, The Netherlands, and Germany, spread within 2 years over large areas of Western and Central Europe, and caused substantial losses in farm ruminants. Especially sheep and cattle were severely affected, leading to a case-fatality ratio of nearly 40% in sheep (Conraths et al., Emerg Inf Dis 15(3):433-435, 2009). The German federal ministry of food, agriculture, and consumer protection (BMELV) established a countrywide monitoring on the occurrence of the vectors of this virus, i.e., midges (family Ceratopogonidae) of the genus Culicoides. The monitoring was done on 91 sites, most of which were localized in the 150-km restriction zone that existed in December 2006. A grid consisting of 45 x 45 km(2) cells was formed that covered the monitoring area. As a rule, one trap was placed into each grid cell. The monitoring program started at the end of March 2007 and lasted until May 2008. It included the catching of midges by ultraviolet light traps-done each month from days 1 until 8, the selection of midges of the Culicoides obsoletus, Culicoides pulicaris group, and other Culicoides spp., the testing of midges for bluetongue virus (BTV) by polymerase chain reaction (PCR), and the daily registration of weather data at each trap site for the whole monitoring period. The following main results were obtained: (1) Members of the C. obsoletus group were most commonly found in the traps, reaching often 3/4 of the catches. The African and South European vector of BTV-the species Culicoides imicola-was never found. (2) Members of the C. obsoletus group were most frequently found infected with BTV besides a few cases in the C. pulicaris group and other species. (3) Members of the C. obsoletus group were also found in winter. Their numbers were reduced, however, and they were caught mostly close to stables. Therefore, a true midge-free period does not exist during the year in Germany. (4) The amounts of midges caught daily depended on the weather conditions. If it was cold and/or windy, the traps contained only a few specimens. Since the months from January to May 2008 were considerably colder (at all farms) than their correspondents in 2007, the growing of the population of midges started 2-3 months later in 2008 than in 2007. (5) The highest populations of midges occurred in both years (2007 and 2008) during the months September and October. This corresponded significantly to the finding of highest numbers of infected midges and to the number of diseased cattle and sheep during these 2 months. (6) It is noteworthy that in general, the first virus-positive midges of the species C. obsoletus were found about 1 1/2 months later than the first clinical cases had occurred or later than the first PCR-proven virus-positive sentinel animals had been documented. In 2007, the first BTV-positive cattle were detected in May in North Rhine-Westphalia, while the first positive Culicoides specimens were only found in August on the same farm. Evaluating these main results of the entomological monitoring and the fact that many wild ruminants have also been infected with BTV, it becomes evident that bluetongue disease has become endemic in Central Europe, and that only constant effort including vaccination and perhaps also insecticidal protection of cattle and sheep will keep the economical losses at a reasonable level. The following papers (1-10) in this journal will contribute more details obtained from this worldwide unique entomological monitoring: Bartsch et al. 2009; Bauer et al. 2009; Stephan et al. 2009; Clausen et al. 2009; Hörbrand and Geier 2009; Kiehl et al. 2009; Mehlhorn et al. 2009; Kiel et al. 2009; Vorsprach et al. 2009; Balczun et al. 2009.

The elimination of rabies from the red fox (Vulpes vulpes) in Western Europe has been achieved by the oral rabies vaccination (ORV) of wildlife with a range of attenuated rabies virus strains. With the exception of the vaccinia rabies glycoprotein recombinant vaccine (VRG), all strains were originally derived from a common ancestor; the Street Alabama Dufferin (SAD) field strain. However, after more than 30 years of ORV it is still not possible to distinguish these vaccine strains and there is little information on the genetic basis for their attenuation. We therefore sequenced and compared the full-length genome of five commercially available SAD vaccine viruses (SAD B19, SAD P5/88, SAG2, SAD VA1 and SAD Bern) and four other SAD strains (the original SAD Bern, SAD VA1, ERA and SAD 1-3670 Wistar). Nucleotide sequencing allowed identifying each vaccine strain unambiguously. Phylogenetic analysis revealed that the majority of the currently used commercial attenuated rabies virus vaccines appear to be derived from SAD B19 rather than from SAD Bern. One commercially available vaccine virus did not contain the SAD strain mentioned in the product information of the producer. Two SAD vaccine strains appeared to consist of mixed genomic sequences. Furthermore, in-del events targeting A-rich sequences (in positive strand) within the 3' non-coding regions of M and G genes were observed in SAD-derivates developed in Europe. Our data also supports the idea of a possible recombination that had occurred during the derivation of the European branch of SAD viruses. If confirmed, this recombination event would be the first one reported among RABV vaccine strains.