Classical swine fever (CSF) is one of the most important viral diseases of domestic pigs (Sus scrofa domesticus) and wild boar (Sus scrofa). For at least 4 decades, several European Union member states were confronted with outbreaks among wild boar and, as it had been shown that infected wild boar populations can be a major cause of primary outbreaks in domestic pigs, strict control measures for both species were implemented. To guarantee early detection and to demonstrate freedom from disease, intensive surveillance is carried out based on a hunting bag sample. In this context, virologic investigations play a major role in the early detection of new introductions and in regions immunized with a conventional vaccine. The required financial resources and personnel for reliable testing are often large, and sufficient sample sizes to detect low virus prevalences are difficult to obtain. We conducted a simulation to model the possible impact of changes in sample size and sampling intervals on the probability of CSF virus detection based on a study area of 65 German hunting grounds. A 5-yr period with 4,652 virologic investigations was considered. Results suggest that low prevalences could not be detected with a justifiable effort. The simulation of increased sample sizes per sampling interval showed only a slightly better performance but would be unrealistic in practice, especially outside the main hunting season. Further studies on other approaches such as targeted or risk-based sampling for virus detection in connection with (marker) antibody surveillance are needed.
The inter-laboratory comparison tests for classical swine fever (CSF) laboratory diagnosis organised by the European Community Reference Laboratory for CSF are regularly performed within European Union Member States. The objective of this study was to evaluate the results of the inter-laboratory comparison tests carried out over the last decade, from 1998 until 2007, by using a statistical approach. A set of five or six lyophilised sera was sent to participants. These included sera containing CSF antibodies, sera containing antibodies against ruminant pestiviruses, sera containing CSF virus and negative sera. This study focused on the results of the diagnostic reference methods for CSF: the neutralisation test for the detection of CSF antibodies (including its interpretation) and virus isolation for the detection of CSF virus. For the detection of CSF antibodies, results were closest to what was expected by the CommunityReference Laboratory when only neutralisation tests were performed. The percentage of correct results decreased as soon as the results of CSF antibody enzyme-linked immunosorbent assay were included or when sera with antibodies to ruminant pestiviruses were added to the panel. The results for the detection of CSF antibodies are still valid today, as no additional method has been introduced recently. Regarding CSF virus detection, CSF virus isolation is well established but on the way to being superseded as the reference test by reverse-transcription polymerase chain reaction.
Since the first detected African swine fever (ASF) cases in Lithuanian wild boar in 2014, the virus has occurred in many other member states of the European Union (EU), most recently in Belgium in 2018 and in Germany in 2020. Passive surveillance and various control measures are implemented as part of the strategy to stop disease spread in the wild boar population. Within this framework, hunters perform important activities, such as the removal of carcasses, fencing or hunting. Therefore, the successful implementation of these measures largely depends on their acceptability by hunters. Methods of participatory epidemiology can be used to determine the acceptance of control measures. The use of participatory methods allows the involvement of key stakeholders in the design, the implementation and the analysis of control and surveillance activities. In the present study, two studies that had been conducted using participatory epidemiology with hunters in Estonia and Latvia were compared on the topics recruitment, participants, facilitators, focus group discussion (FGDs) and their contents. The aim was to evaluate similarities and differences in the two studies and to identify a broader spectrum of possibilities to increase the willingness of hunters supporting the fight against ASF. Evaluating all conducted FGDs in both countries showed primarily similarities in the perceptions and opinions of the hunters in Estonia and Latvia. One notable difference was that passive surveillance in Latvia was perceived mostly as topic of duty and ethics rather than an issue driven by incentives. Participatory methods have proven to be an effective tool in the evaluation of the acceptance of established ASF control systems. The results of this study point out further chances for improving the cooperation with hunters in the future. Nevertheless, the importance of gathering and analyzing the opinions of hunters in all ASF affected countries individually is highlighted.
Since the first detected African swine fever (ASF) cases in Lithuanian wild boar in 2014, the virus has occurred in many other member states of the European Union (EU), most recently in Belgium in 2018 and in Germany in 2020. Passive surveillance and various control measures are implemented as part of the strategy to stop disease spread in the wild boar population. Within this framework, hunters perform important activities, such as the removal of carcasses, fencing or hunting. Therefore, the successful implementation of these measures largely depends on their acceptability by hunters. Methods of participatory epidemiology can be used to determine the acceptance of control measures. The use of participatory methods allows the involvement of key stakeholders in the design, the implementation and the analysis of control and surveillance activities. In the present study, two studies that had been conducted using participatory epidemiology with hunters in Estonia and Latvia were compared on the topics recruitment, participants, facilitators, focus group discussion (FGDs) and their contents. The aim was to evaluate similarities and differences in the two studies and to identify a broader spectrum of possibilities to increase the willingness of hunters supporting the fight against ASF. Evaluating all conducted FGDs in both countries showed primarily similarities in the perceptions and opinions of the hunters in Estonia and Latvia. One notable difference was that passive surveillance in Latvia was perceived mostly as topic of duty and ethics rather than an issue driven by incentives. Participatory methods have proven to be an effective tool in the evaluation of the acceptance of established ASF control systems. The results of this study point out further chances for improving the cooperation with hunters in the future. Nevertheless, the importance of gathering and analyzing the opinions of hunters in all ASF affected countries individually is highlighted.
Infections with Classical swine fever virus (CSFV) are a major economic threat to pig production. To combat CSF outbreaks and to maintain trade, new marker vaccines were developed that allow differentiation of infected from vaccinated animals (DIVA principle). The chimeric pestivirus CP7_E2alf was shown to be safe and efficacious. Its DIVA strategy is based on the detection of CSFV Erns-specific antibodies that are only developed on infection. However, for the new marker vaccine to be considered a valuable control tool, a validated discriminatory assay is needed. One promising candidate is the already commercially available enzyme-linked immunosorbent assay, PrioCHECK CSFV Erns ELISA (Prionics BV, Lelystad, The Netherlands). Four laboratories of different European Union member states tested 530 serum samples and country-specific field sera from domestic pigs and wild boar. The ELISA displayed a good robustness. However, based on its reproducibility and repeatability, ranges rather than single values for diagnostic sensitivity and specificity were defined. The ELISA displayed a sensitivity of 90–98% with sera from CSFV-infected domestic pigs. A specificity of 89–96% was calculated with sera from domestic pigs vaccinated once with CP7_E2alf. The ELISA detected CSFV infections in vaccinated domestic pigs with a sensitivity of 82–94%. The sensitivity was lower with sera taken ≤21 days post-challenge indicating that the stage of CSFV infection had a considerable influence on testing. Taken together, the PrioCHECK CSFV Erns ELISA can be used for detection of CSFV infections in CP7_E2alf-vaccinated and nonvaccinated domestic pig populations, but should only be applied on a herd basis by testing a defined number of animals.
In this era of globalisation the effective control of animal disease outbreaks requires powerful crisis management tools. In the 1990s software packages for different sectors of the government and agricultural industry began to be developed. In 2004, as a special application for tracking the movement of animals and animal products, the European Union developed the Trade Control and Expert System (TRACES) on the basis of its predecessor, the ANImal MOvement (ANIMO) project. The nationwide use of the ANIMO system by the veterinary authorities in Germany marked the beginning of the development in 1993 of a computerised national animal disease reporting system – the TierSeuchenNachrichten /TSN) - using the ANIMO hardware and software components. In addition to TRACES and TSN the third pillar for the management of animal disease outbreaks and crises in Germany is the national cattle and swine database – called Herkunftssicherungs- und Informationssystem für Tiere. A high degree of standardisation is necessary when integrating the different solutions at all levels of government and with the private sector. In this paper, the authors describe the use of these tools on the basis of their experience and in relation to what we can do now and what we should opt for in the future.
Bait disappearance can give valuable information for the assessment of oral vaccination campaigns of foxes against rabies. In this study, the spatial and temporal disappearance of three different vaccine baits under almost identical conditions was investigated. In the study area, 350 baits were placed at previously marked positions during two different periods; late autumn and early spring. The distribution of baits was in accordance with the method as recommended by the European Union; a density of 20 baits per km2 along flight lines 500m apart. Bait disappearance was checked 1, 3, 5 and 7 days after distribution. At least 80 % of the baits had disappeared within one week after distribution. No difference in bait disappearance was observed between the two selected periods. However, a significant higher bait disappearance was observed in forested areas when compared to open agricultural areas. Furthermore, the differences in bait disappearance between the three type of baits tested were relatively small and not significant. ; Das Verschwinden von Impfköder im Feld kann wichtige Information für die Evaluierung von Impfkampagnen im Rahmen der oralen Immunisierung von Füchsen gegen die Tollwut liefern. In dieser Feldstudie wurde das Verschwinden von drei unterschiedlichen Ködern in Zeit und Raum unter gleichen Bedingungen während zweier Jahreszeiten (Herbst und Frühjahr) untersucht. Insgesamt wurden 350 Köder entsprechend den Empfehlungen der Europäischen Union an gekennzeichneten Stellen entlang simulierter Fluglinien, die 500 m auseinander lagen, und einer Köderdichte von 20 Köder pro km2 ausgelegt. Die Köderstellen wurden einen, drei, fünf und sieben Tage nach der Auslage kontrolliert. Mindestens 80 % der Köder waren innerhalb einer Woche nach der Auslage verschwunden, wobei keine Unterschiede im Anteil der verschwunden Köder zwischen Herbst und Frühjahr festgestellt wurden. Während zwischen den drei unterschiedlichen Ködern nur geringfügige, nicht signifikante Unterschiede in der Verschwinderate bestanden, war die Verschwinderate der Köder im Wald signifikant höher als im offenen Gelände.
Objective: Classical Swine Fever (CSF) is a highly contagious viral disease, which affects all suid species. CSF infection in wild boar can play an important role in disease introduction to commercial pig holdings. Due to its high economic impact, efficient but also cost-effective surveillance strategies have to be implemented not only in commercial pig holdings but also in wild boar. In Germany, the last CSF outbreak occurred in wild boar in 2009. Consequently, vaccination had been implemented until 2012. Since June 2012, Germany is considered to be free from CSF. Following this, active surveillance in wild boar has been carried out according to the directives of the European Union (Council directive 2001/89/EC). Germany's implementation of these regulations plan to take 59 samples per district per year to be capable to demonstrate freedom from disease on district level (conventional method). Compared to conventional surveillance, risk-based surveillance approaches may achieve similar performance at lower cost or better performance at the same cost. Within the framework of the European project RISKSUR (http://www.fp7-risksur.eu/) we conducted a simulation study to compare the performances of different surveillance approaches for CSF in an unvaccinated wild boar population in an area free from the disease. The aim of the study was to find out whether surveillance with the objective of demonstrating freedom from disease in wild boar could be designed more effectively using risk-based or alternative methods compared to using conventional methods. Methods: For the simulation model, R (www.r-project.org) was used for statistical computing and displaying graphs. A virtual wild boar population was generated and an infection initiated within this population. As study area we used the federal state of Rhineland Palatinate. The population size estimates for the considered region, determined using fecal DNA samples, were used to calculate the total number of wild boar within the simulation study. To assure a general pattern of the population structure we chose districts from three areas with different epidemiological situations. The simulated population was structured containing information on age, gender and the type of carcass (shot healthy, shot sick, injured through road traffic accident and found dead). The setup of the infection was done on the basis of data from Mecklenburg-Western Pomerania to estimate the increase of the seroprevalence at the beginning of an infection. The risk factor analysis used to define the risk-based surveillance approaches was done through literature search, expert opinion and bivariate analysis of infection data. Due to a lack of appropriate information in Rhineland Palatinate, infection data of the federal state of Mecklenburg-Western Pomerania were used as data basis as well. The simulation was conducted on the basis of real hunting data of Rhineland Palatinate and the surveillance approach, performed following the regulations of the European Union was simulated With these simulations, the probability of case detection and the time until the first case detection were determined and used as reference values. These values were then compared to the values resulting from the simulation of different alternative and risk-based surveillance methods. Alternative surveillance methods were increased sampling in the age class at higher risk of infection or in the season with an assumed higher detection probability. Furthermore we simulated the sampling in dependence of the population density in the different districts in two different ways. One approach was to sample only in districts were the population density was above a predefined threshold, whereas the other approach was to determine the sample size in the individual districts in dependence of the population density. Results: The results of the fecal DNA analyses showed an estimated mean of 2,593 wild boar per district with a maximum of 8,524 and a minimum of 30 wild boar (median: 2,163). The real hunting data collected in specified districts (27 districts) of Rhineland Palatinate between 2003 and 2014 constituted the basis for the age and sex structure of the simulated population. In total we had 105,439 records. In the analyzed data the sex proportion of shot male and female animals was almost equal (male: 52.4%; female: 47.6%). The age distribution showed that the number of shot animals aged less than one year were highest (55.1%) and the number of samples coming from animals over 2 years was lowest (10.8%). Almost all samples (99.6%) were collected from hunted healthy animals, i.e. from active surveillance. Most samples were taken in the months of November (15.92%), December (13.68%) and January (12.57%). For the simulation of hunting, averaged values of the hunting bag data from 2003-2011 were used. In average 1,340 wild boar/district/year were hunted (min: 0; max: 4,573; median: 1,113). For the setup of the infection into the simulated population, data from Mecklenburg-Western Pomerania were used. They consisted of 17,492 data sets resulting from the years 1993 and 1994, which were collected in six non-vaccination districts. Within this dataset, 2,652 samples had tested seropositive for CSF. Due to the low number of positive cases identified through serological and virological testing in the data set of Rhineland-Palatinate, surveillance data from non-vaccination districts within Mecklenburg-Western Pomerania were used for risk analysis. The data consisted of 85,105 data sets from 1994-2000. The sex, age and carcass distribution showed a similar pattern as the data from Rhineland-Palatinate. Bivariate analysis showed that age plays a role in the probability of being serologically or virologically positive. These findings were supported by the findings of the literature search as well as by expert opinion. In the literature, it was found that the probability of samples gathered through passive surveillance being positive is assumed to be higher. However, the low number of available passive surveillance data made it impossible to support this assumption through statistical analysis. Additionally, experts suggest that seasonality of the hunting and infection as well as population density may be considered as risk factors for infection. The following initial results refer to simulations in a defined area of Rhineland Palatinate consisting of three neighboring districts. From 1000 simulation repetitions of sampling 59 samples per district over the year, by serological examination the infection was detected 1000 times per district (reference value for detection probability). On average 331 cases were detected in the first month of infection (reference value for time until first case is detected). By serological investigations of 59 animals aged less than 1 year infection was not detected at all in 11 simulation runs. On average 162 cases were detected within the first month. However, investigating 59 animals aged over 2 years serologically, the infection was detected 1000 times and 688 times already in the first month of infection. Conclusion: The first results of the simulation model indicate that alternative surveillance strategies show a similar probability of detection. However, serological surveillance of animals aged over two years reduced the time until the first case was detected significantly. Additionally, it might be assumed that through changes in sampling strategies e.g. based on population density thresholds, a reduction of costs is possible. The resulting financial resources could be used to increase sampling following the risk based approaches, therefore increasing the detection probability. They could also be used for campaigns supporting for example passive surveillance. However, the effectiveness of the single surveillance approaches should not only be measured by the outputs of the model, but also through a comprehensive evaluation of the whole surveillance system, including acceptability and practicability of the system. Moreover, the surveillance could be designed taking different risk factors into account and could therefore have the potential to result in a better performance. If higher numbers of animals found dead were investigated, passive surveillance would be an alternative. However, also in the future it will be difficult to reach higher numbers of samples from passive surveillance. Finally it has to be mentioned that due to the limitation of getting accurate population abundance data in wild life, designing surveillance schemes and the establishment of effective surveillance strategies will always constitute a certain challenge.
Starting August 2006, a major epidemic of bluetongue (BT) was identified in North-West Europe, affecting The Netherlands, Belgium, Germany, Luxemburg and the North of France. It was caused by BT virus scrotype 8 (BTV-8), a serotype previously unknown to the European Union (EU). In this outbreak, the virus caused clinical disease in a few individual animals within cattle herds, whereas overt clinical disease was usually restricted to sheep. Investigations in Belgium suggested that the first clinical signs of BTV-8 appeared mid July 2006 in a cattle herd, while the first suspicion of a BT-outbreak in Belgium was reported on 17 August 2006. In the first 10 BTV-8 outbreaks in the Netherlands, the owners indicated that the first clinical signs started approximately 12-17 days before a suspicion was reported to the veterinary authorities via a veterinary practitioner. In BTV-8 affected sheep flocks, erosions of the oral mucosa, fever, salivation, facial and mandibular oedema, apathy and tiredness, mortality, oedema of the lips, lameness, and dysphagia were among the most frequent clinical signs recorded. The most prominent clinical signs in BTV-8 affected cattle herds were: crusts/lesions of the nasal mucosa, erosions of lips/crusts in or around the nostrils, erosions of the oral mucosa, salivation, fever, conjunctivitis, coronitis, muscle necrosis, and stiffness of the limbs. Crusts/lesions of nasal mucosa, conjunctivitis, hyperaemic/purple coloration and lesions of the teats, and redness/hypersensitivity of the skin were relatively more seen on outbreak farms with cattle compared to sheep. Mortality, oedema of the head and ears, coronitis, redness of the oral mucosa, erosions/ulceration of tongue mucosa, purple coloration of the tongue and tongue protrusion and dyspneu were relatively more seen on outbreak farms with sheep compared to cattle. (C) 2008 Elsevier B.V. All rights reserved
No human infections due to highly pathogenic avian influenza (HPAI) A(H5N8) or A(H5N6) viruses ‐ detected in wild birds and poultry outbreaks in Europe ‐ have been reported so far and the risk of zoonotic transmission to the general public in Europe is considered very low. Between 16 November 2018 and 15 February 2019, two HPAI A(H5N8) outbreaks in poultry establishments in Bulgaria, two HPAI A(H5N6) outbreaks in wild birds in Denmark and one low pathogenic avian influenza (LPAI) A(H5N3) in captive birds in the Netherlands were reported in the European Union (EU). Genetic characterisation of the HPAI A(H5N6) viruses reveals that they cluster with the A(H5N6) viruses that have been circulating in Europe since December 2017. The wild bird species involved were birds of prey and were likely infected due to hunting or scavenging infected wild waterfowl. However, HPAI virus was not detected in other wild birds during this period. Outside the EU, two HPAI outbreaks were reported in poultry during the reporting period from western Russia. Sequence information on an HPAI A(H5N6) virus found in a common gull in western Russia in October 2018 suggests that the virus clusters within clade 2.3.4.4c and is closely related to viruses that transmitted zoonotically in China. An increasing number of outbreaks in poultry and wild birds in Asia, Africa and the Middle East was observed during the time period for this report. Currently there is no evidence of a new HPAI virus incursion from Asia into Europe. However, passive surveillance systems may not be sensitive enough if the prevalence or case fatality in wild birds is very low. Nevertheless, it is important to encourage and maintain a certain level of passive surveillance in Europe testing single sick or dead wild birds and birds of prey as they may be sensitive sentinel species for the presence of HPAI virus in the environment. A well‐targeted active surveillance might complement passive surveillance to collect information on HPAI infectious status of apparently healthy wild ...
No human infections due to highly pathogenic avian influenza (HPAI) A(H5N8) or A(H5N6) viruses ‐ detected in wild birds and poultry outbreaks in Europe ‐ have been reported so far and the risk of zoonotic transmission to the general public in Europe is considered very low. Between 16 November 2018 and 15 February 2019, two HPAI A(H5N8) outbreaks in poultry establishments in Bulgaria, two HPAI A(H5N6) outbreaks in wild birds in Denmark and one low pathogenic avian influenza (LPAI) A(H5N3) in captive birds in the Netherlands were reported in the European Union (EU). Genetic characterisation of the HPAI A(H5N6) viruses reveals that they cluster with the A(H5N6) viruses that have been circulating in Europe since December 2017. The wild bird species involved were birds of prey and were likely infected due to hunting or scavenging infected wild waterfowl. However, HPAI virus was not detected in other wild birds during this period. Outside the EU, two HPAI outbreaks were reported in poultry during the reporting period from western Russia. Sequence information on an HPAI A(H5N6) virus found in a common gull in western Russia in October 2018 suggests that the virus clusters within clade 2.3.4.4c and is closely related to viruses that transmitted zoonotically in China. An increasing number of outbreaks in poultry and wild birds in Asia, Africa and the Middle East was observed during the time period for this report. Currently there is no evidence of a new HPAI virus incursion from Asia into Europe. However, passive surveillance systems may not be sensitive enough if the prevalence or case fatality in wild birds is very low. Nevertheless, it is important to encourage and maintain a certain level of passive surveillance in Europe testing single sick or dead wild birds and birds of prey as they may be sensitive sentinel species for the presence of HPAI virus in the environment. A well‐targeted active surveillance might complement passive surveillance to collect information on HPAI infectious status of apparently healthy wild bird populations.
To prevent disease transmission into commercial animal herds meaningful and reliable surveillance must not only focus on livestock but also wildlife. For the assessment of the overall performance of a surveillance system investigating different evaluation attributes is recommended (http://www.fp7-risksur.eu/). In the presented study we performed a comprehensive evaluation of alternative risk-based surveillance strategies for Classical Swine Fever (CSF) in wild boar - a disease of high economic impact. On the basis of a risk factor analysis we developed different surveillance strategies for comparative economic evaluation. The current surveillance strategy, specified by the European Union, constituted the reference strategy. To evaluate the effectiveness of the surveillance strategies we investigated sensitivity and timeliness. This was done using a simulation model. Acceptability, which provides evidence on the functional aspect of the surveillance strategies, was investigated using participatory methods. The cost-effectiveness of the surveillance strategies was investigated based on the simulation model results. Using the identified risk factors 69 surveillance strategies including the conventional strategy were generated and evaluated. Sampling only in the defined age class of sub-adult wild boar resulted in the best overall performance. The results of this study suggest that risk-based surveillance strategies can be an option to design more efficient surveillance. The study could be used as a template for further evaluation studies of surveillance of different animal diseases.
In August 2006, bluetongue (BT) was notified in The Netherlands on several animal holdings. This was the onset of a rapidly spreading BT-epidemic in north-western Europe (latitude >51 degrees N) that affected cattle and sheep holdings in The Netherlands, Belgium, Germany, France and Luxembourg. The outbreaks were caused by bluetongue virus (BTV) scrotype 8, which had not been identified in the European Union before. Bluetongue virus can be introduced into a free area by movement of infected ruminants, infected midges or by infected semen and embryos. In this study, information on animal movements or transfer of ruminant germ plasms (semen and embryos) into the Area of First Infection (AFI), which occurred before and during the onset of the epidemic, were investigated in order to establish the conditions for the introduction of this virus. All inbound transfers of domestic or wild ruminants, non-susceptible mammal species and ruminant germ plasms into the AFI during the high-risk period (HRP), registered by the Trade Control and Expert System (TRACES) of the EC, were obtained. Imports originating from countries with a known or suspected history of BTV-incidence of any scrotype were identified. The list of countries with a reported history of BTV incidence was obtained from the OIE Handistatus II for the period from 1996 until 2004. No ruminants were imported from a Member State (MS) with a known history of BTV-8 or from any other country with a known or suspected history of BTV incidence of any serotype. Of all non-susceptible mammal species only 233 horses were transported directly into the AFI during the HRP. No importations of semen or embryos into the AFI were registered in TRACES during the period of interest. An obvious source for the introduction of BTV-8, such as import of infected ruminants, could not be identified and the exact origin and route of the introduction of BTV-8 thus far remains unknown. However, the absence of legal import of ruminants from outside the EU into the AFI and the absence of BTV-8 in southern Europe suggest that, the introduction of the BTV-8 infection into the north-western part of Europe took place via another route. Specifically, in relation to this, the potential for Culicoides to be imported along with or independently of the import of animals, plants or other 'materials', and the effectiveness of measures to reduce such a possibility, merit further study. (C) 2008 Published by Elsevier B.V
Between 16 August and 15 November 2018, 14 highly pathogenic avian influenza (HPAI) A(H5N8) outbreaks in poultry establishments in Bulgaria and seven HPAI A(H5N6) outbreaks, one in captive birds in Germany and six in wild birds in Denmark and the Netherlands were reported in the European Union (EU). No human infection due to HPAI A(H5N8) and A(H5N6) viruses have been reported in Europe so far. Seroconversion of people exposed during outbreaks in Russia has been reported in one study. Although the risk of zoonotic transmission to the general public in Europe is considered to be very low, appropriate personal protection measures of people exposed will reduce any potential risk. Genetic clustering of the viruses isolated from poultry in Bulgaria suggests three separate introductions in 2016 and a continuing circulation and transmission of these viruses within domestic ducks. Recent data from Bulgaria provides further indication that the sensitivity of passive surveillance of HPAI A(H5N8) in domestic ducks may be significantly compromised. Increased vigilance is needed especially during the periods of cold spells in winter when aggregations of wild birds and their movements towards areas with more favourable weather conditions may be encouraged. Two HPAI outbreaks in poultry were reported during this period from western Russia. Low numbers of HPAI outbreaks were observed in Africa and Asia, no HPAI cases were detected in wild birds in the time period relevant for this report. Although a few HPAI outbreaks were reported in Africa and Asia during the reporting period, the probability of HPAI virus introductions from non-EU countries via wild birds particularly via the north-eastern route from Russia is increasing, as the fall migration of wild birds from breeding and moulting sites to the wintering sites continues. Furthermore, the lower temperatures and ultraviolet radiation in winter can facilitate the environmental survival of any potential AI viruses introduced to Europe.
Die Afrikanische Schweinepest (ASP) ist aufgrund ihrer schweren sozioökonomischen Konsequenzen, der unvorhersehbaren internationalen Verbreitung sowie fehlender Möglichkeiten zur therapeutischen oder impfprophylaktischen Bekämpfung eine der wichtigsten Tierseuchen des Schweines. Im Jahr 2014 erreichte die ASP die Ostgrenze der EU. Im Januar 2014 meldete Litauen die ersten ASP-positiven Wildschweine, es folgten im Februar Meldungen aus Polen, im Juni aus Lettland und im September 2014 aus Estland. Die Ausbrüche in den Hausschweinbeständen konnten schnell und problemlos getilgt werden. Im Gegensatz dazu erweist sich das Geschehen in der Wildschweinpopulation als sehr komplex und schwer kontrollierbar. Feldbeobachtungen und experimentelle Studien deuten auf eine hohe Letalität und geringe Kontagiosität in der Anfangsphase der ASP hin. Die geringe Kontagiosität erfordert ein Umdenken und ein dementsprechend angepasstes Vorgehen bei der Bekämpfung im Wildschweinbereich. Bei der Bekämpfung der Tierseuche beim Hausschwein erweist sich die geringe Kontagiosität als ein Vorteil (genügend Zeit, um die Maßnahmen durchzuführen), beim Wildschwein hingegen ist sie ein Nachteil, wenn andere Faktoren wie hohe Wildschweindichten und lange Überlebenszeiten des Virus in der Natur die Bekämpfung erschweren. Nach bisherigen Erkenntnissen verhält sich die ASP in einer Wildschweinpopulation eher wie eine langjährige (eher stationäre), an das Habitat gebundene Seuche ohne Tendenz zur schnellen Ausbreitung. Dabei könnten vornehmlich infektiöse Kadaver in Verbindung mit der hohen Tenazität des ASP-Virus und der niedrigen Kontagiosität die Tierseuche in einer Region "binden". Dieses Phänomen könnte erklären, warum sich die ASP zwar langsam ausbreitet, das Infektionsgeschehen jedoch nicht von selbst erlischt. ; African swine fever (ASF) is considered internationally as one of the most dangerous animal diseases of pigs. The dis ease is affecting trade and having serious socio-economic impact on people's livelihood. No drugs or vaccines are available to fight ASF. ASF has reached the eastern borders of the European Union in January 2014. The very first cases of infected wild boar have been reported by Lithuania. Poland reported first cases in February, followed by Latvia in June and Estonia later in September of that same year. The outbreaks occurring in domestic pigs have been controlled timely and without major problems. Within the wild boar population however, the occurrence of ASF has shown to be very complex and difficult to control. Field data as well as experimental studies on ASF indicate an overall high case-fatality rate and a rather low contagiosity during the initial phase of infection. Within that context, a revision of the current understanding and approaches towards ASF control and eradication is needed. In domestic swine populations the low contagiosity is rather an advantageous feature reducing the urgency in the implementation of control measures. For wild boar however, in combination with the environmental stability of the virus and high animal densities, the low contagiosity represents a disadvantage for effective control. Current findings indicate that in wild boar populations ASF shows a pattern of habitat bound persistence lacking a tendency of dynamic spatial spread. Therefore ASF in wild boar can be considered a habitat-borne disease where infected carcasses in combination with the tenacity of the virus and the low contagiosity play a key role in capturing the disease within affected areas. Such circumstances are likely to contribute substantially to months or even years of pathogen persistence explaining the current picture of ASF spreading rather slowly and with continuing circulation in affected areas.