Classical Swine Fever - available
Control ToolsDiagnostics availabilityYes, RT-PCR as well as ELISA kits. RT-PCR has been found to be the most sensitive method for detection of CSFV (Dewulf et al., 2004; Handel et al., 2004; Depner et al., 2006a; Depner et al., 2007a, Le Dimna et al., 2008). In general it can be said that from an RT-PCR negative result it can be concluded with a very high confidence that the tested animal or tissue sample is not infectious to other pigs at the moment of sampling. Recently, commercial RT-PCR kits have been developed (for real-time PCR). Commercial ELISA kits are available by different manufacturers, both for antigen and antibody detection. Commercially available monoclonal antibodies and conjugates can be used for different staining techniques. GAPS:
Yes, RT-PCR as well as ELISA kits. RT-PCR has been found to be the most sensitive method for detection of CSFV (Dewulf et al., 2004; Handel et al., 2004; Depner et al., 2006a; Depner et al., 2007a, Le Dimna et al., 2008). In general it can be said that from an RT-PCR negative result it can be concluded with a very high confidence that the tested animal or tissue sample is not infectious to other pigs at the moment of sampling. Recently, commercial RT-PCR kits have been developed (for real-time PCR). Commercial ELISA kits are available by different manufacturers, both for antigen and antibody detection. Commercially available monoclonal antibodies and conjugates can be used for different staining techniques. GAPS:
Routine methods are described in both the OIE Manual of Diagnostic Tests and Vaccines as well as in the Technical Annex accompanying the EU Diagnostic Manual (Commission Decision 2002/106/EC). GAP: New developments should be implemented on a regular basis. Routine methods are described in both the OIE Manual of Diagnostic Tests and Vaccines as well as in the Technical Annex accompanying the EU Diagnostic Manual (Commission Decision 2002/106/EC). GAP: New developments should be implemented on a regular basis. Compared to other veterinary pathogens there is only a limited market for diagnostics for exotic diseases. Thus the incentive for the development of new diagnostic kits is not very high. Customers ask for a large number of ELISA tests ready for use in case of a contingency, but usually only a few tests are sold in peacetime. GAP: No commercial incentives to develop new tests or improve existing tests. Novel live DIVA vaccines are really important now, for wild boar and countries where the semi wild pig species form a large reservoir for the virus. Pigs vaccinated with a sub-unit marker vaccine only develop antibodies against the E2 glycoprotein whereas pigs that have been naturally infected develop antibodies against different viral proteins (e.g. E2, ERNS, NS3). Consequently, it is possible to distinguish between an infected and a vaccinated pig (DIVA) by means of an ELISA test that detects antibodies only against the ERNS glycoproteins upon infection (Moormann et al., 2000). Two differential diagnostic ERNS antibody ELISA tests (ERNS -antibody ELISAs) are on the market (SCAHAW, 2003, Blome et al., 2006). GAPS: The current DIVA ELISAs detecting antibodies to the Erns protein are not as sensitive and selective as E2 antibody ELISAs. So Erns antibodies are detected at a later stage than E2 antibodies. This may cause a gap, during which an infected animal is not correctly detected with the ‘Erns Elisas. For the new generation of marker vaccines potent companion tests are necessary. Samples from infected semi wild boar should be available for research, they will improve the diagnostic tremendously if we had access to field samples from these infected areas, and it will also help the local laboratories if somebody visit them and try out their test systems there. Test systems for antibody and antigen detection and also PCR are already commercially available. At the moment only modified live (MLV) “C-strain” vaccines are available as CSF-vaccines in the European Union. The future of the only remaining registered DIVA vaccine (E2-subunit) in its present form is uncertain (EMEA decision 2009). Therefore, all vaccination strategies of domestic pigs in the near future have to focus on non-DIVA MLV vaccines. However, new approaches like antigen storage might also allow the storage of E2-subunit vaccines in a vaccine bank. GAPS:
Vaccines availabilityC-strain, live vaccine, brilliant performance. Several other vaccines CPG, Pestiffa etc are based on the old Chinese idea of live vaccines. Nice and effective live vaccines exist and are widely used for domestic pigs as injection vaccines and for wild boars as oral vaccines. New approaches are DIVA vaccines, where one is commercially available, but they have not till now been used widely, apart from in Romania. Some local vaccines of undefined quality available in other countries. GAPS:
All MLV that are accepted in EU are also available worldwide. The cost per dose may decide if other countries can afford them. GAP: Live DIVA vaccines. E2 allowing discrimination based on ERNS For example, an E2 marker vaccine exists. Novel marker concepts are under development (EU-FP7 227003 CP-FP CSFgo_DIVA). GAPS: More data on new live DIVA vaccine candidates EU-FP7 227003 CP-FP CSFgo_DIVA). Potent companion tests for new marker vaccines. Assessment of safety of modified strategies in order to increase international market acceptance for products from vaccinated animals. The registered marker vaccine based on baculo expressed E2 envelope protein of CSFV and an ERNS antibody detection test corresponding to it. During the development of marker vaccines it became clear that the E2-glycoprotein in a purified form was capable of inducing a protective immunity. This finding was the basis for the development of an E2 subunit vaccine that contains as antigen only the E2 glycoprotein of CSFV. The recombinant E2 glycoprotein is produced in cultures of insect cells infected with the baculovirus vector (Hulst et al., 1993). No marker vaccines are available at the moment since one E2-subunit vaccine (Pfizer) was cancelled by the company, and the other E2-DIVA vaccine is not approved since a few months. GAP: Uncertainty concerning registration procedures of live marker vaccine. Animals vaccinated with conventional live vaccines cannot be differentiated serologically from infected animals. Pigs vaccinated with marker vaccines and infected by ruminant pestiviruses may register positive in the discriminatory test due to cross-reaction/lack of test specificity (this will be the fact even if they have not been vaccinated previously). Live vaccines are effective even when vaccination takes place only a few days before infection, whereas subunit marker vaccines require at least a 2-3 weeks before full immunity. According to manufacturer`s instructions E2-subunit vaccines require two injections to confer solid protection. The immune response against E2-subunit vaccines is shorter compared to live vaccines and it does not confer full foetal protection. In general, most MLV (e.g. C-strain vaccines) are reported as highly efficacious after a single oral or parenteral vaccine application and the onset of protection starts very shortly (few days) after vaccination. In contrast, E2sub are described as most efficacious after booster injection and full of immunity was not before three weeks post vaccination. GAPS:
Commercial potential exists in endemic countries, outside Europe. Within Europe commercial potential exists for orally applicable MLVs for use in infected wild boar populations. DIVA vaccines for the European market are interesting but there is a severe need for EU contribution to this as the companies themselves will probably not be able to make these vaccines profitable in the EU. With the enlargement there may be a larger market. DIVA live vaccines produced as recombinant vaccines should be recommended. GAPS: Commercial incentives for development and licensing of DIVA live vaccines are lacking, idem for live marker vaccine. Use of genetically modified vaccines might be problematic in some countries. GAP: It is unclear whether GMOs as vaccines will be licensed. GAP: Development and production of “new” type of baits for wild boar is not yet completely solved. In principle it is possible to use vaccination as a measure to prevent entry or spread of CSF (cordon sanitaire vaccination). However, direct or indirect contacts may occur to non-vaccinated pigs outside this area due to increased mobility (personnel, pig transports, meat). Chimeric pestivirus constructs are the most promising second generation candidates for a modified live CSF DIVA vaccine with the potential to combine the efficacy of MLV with the marker properties of E2subV (Dong et al., 2006, Beer et al., 2007, Wehrle et al. 2007, Holinka et al, 2009). Pharmaceutical availabilityThere is no therapy for CSFV and in Europe any treatment is forbidden by EC legislation. Antivirals like BPIP might be potential candidates. GAP: Knowledge on use of antivirals is yet scarce. Further studies are needed. Antiviral substances which prevent or diminish the shedding of CSFV by infected pigs might become commercially interesting in the future. GAP: Need for the definition of the registration process of antivirals : definition of minimal requirements , ex safety , efficacy, etc.. Comments NA Antivirals may offer new additional tools for CSF control. GAPS:
New developments for diagnostic testsNew tests are constantly being developed. There is a continuous need for the improvement of diagnostic tests in terms of sensitivity, specificity, costs, practicability, and robustness. The latest developments in nucleic acid diagnosis and test automation should be exploited. Pen side tests could be interesting tools; however, their role in the control of notifiable diseases is discussed controversially. More robust serological tests for feral pigs are needed, i.e. tests which tolerate highly haemolysed samples without problems. Money should be allocated to those parties that actually develop new tests in order to further validate them. Validation data of tests should be made available to other parties. GAPS:
In general the development of tests is much faster and less expensive compared to vaccine development. Time and costs depend on the nature of the test. Still several years elapse until a test becomes available as diagnostic tool and even longer until it is commercially marketed. Developing and validating new diagnostic tests is a time- and labour consuming task, which is rather costly. Costs can not be specified exactly as they surely depend on the nature of the test. Cooperation between diagnostic/research lab with expertise in diagnostic techniques and commercial companies with expertise in licensing and marketing such products is absolutely necessary. GAPS:
Cooperation and serious involvement of labs with a combination of research and diagnostic is necessary. The industry should be more interested in supporting CSFV research. GAP: Testing of samples derived from the national domestic pig herd (negative samples collected for other purposes) for test validation might cause legal problems in some countries. Freedom from virus can only be certified by repeated RT-PCR analyses of the same animal within a certain time frame, while it is kept in quarantine in the meantime. GAP: Modern techniques are much better than the methods used in the past and can provide a very good diagnosis with a minimum error rate. However, it is impossible to guarantee 100% freedom of disease for any population. Minimum requirements for monitoring should be agreed upon internationally. New developments for vaccinesImprove DIVA vaccines, they need to be live for quick onset of immunity and in order to require only one shot and preferably also for oral consumption. The accompanying test should not interfere with antibodies induced by other pestiviruses. AB tests on non-blood materials would be a possibility. Better test on wild or feral pigs, i.e. must endure highly haemolysed samples without problems. GAP: Whereas the European Pharmacopoea only deals with drugs and vaccines, there is no link between the marker vaccine and the accompanying diagnostic (marker) assays. It always needs time to improve a vaccine. A period of 5-10 years for the development, clinical trials and licensing is realistic. GAP: Commercial incentives are lacking. Very expensive and a small probability of a large market in Europe. However, outside Europe there could be a substantial market for live DIVA vaccines, since these are much cheaper to produce than the subunit DIVA vaccines, which are too expensive for many countries, especially outside Europe. GAP: Funding of research activities by non-commercial bodies is absolutely essential. Cooperation and serious involvement of labs with a combination of research and diagnostic is necessary. Especially for the subsequent test of vaccinated and/or infected animals. The market size in Europe for (live) DIVA vaccines is a critical factor. GAP: Closer cooperation and contact between European and Non-EU laboratories needs to be established. New developments for pharmaceuticalsPotential of antiviral substances needs to be further elucidated. GAPS: Lack of commercial incentives. Establish criteria for:
Five to ten years seems to be a realistic time frame. GAP: Commercial incentives are lacking. Very expensive and a small probability of a large market in Europe. However, outside Europe there could be a substantial market for live DIVA vaccines, since these are much cheaper to produce than the subunit DIVA vaccines, which are too expensive for many countries, especially outside Europe. GAPS: Funding of research activities by non-commercial bodies is absolutely essential. Cooperation and serious involvement of labs with a combination of research and diagnostic is necessary. Especially for the subsequent test of vaccinated and/or infected animals. The market size in Europe for (live) DIVA vaccines is a critical factor. GAP: Closer cooperation and contact between European and Non-EU laboratories needs to be established. Disease detailsDescription and characteristics.Pestivirus, Flaviviridae. Lipid-enveloped RNA virus. Closely related to the ruminant pestiviruses that cause bovine viral diarrhea and border disease. GAP: Genomic stability/instability (quasispecies) and the factors that influence virus stability and recombination. The virus has only one serotype, although some minor antigenic and genomic variability between strains can be shown (genotypes). Variability in virulence: acute (high mortality – up to 100%), sub-acute (lower morbidity and mortality rates), chronic (few animals affected – always fatal), some asymptomatic cases. The outcome of the disease is influenced by the infecting virus isolate as well as age class and immune status of the infected pig. The only natural hosts known are members of the family Suidae. GAPS:
Moderately fragile and does not persist in the environment. Sensitive to drying and ultraviolet light. Survives well in pens during cold conditions (up to 4 weeks in winter). Survives 3 days at 50°C and 7-15 days at 37°C. Survives in meat during salt curing and smoking for 17 to >180 days depending on the process used. Virus persists 3–4 days in decomposing organs and 15 days in decomposing blood and bone marrow. Stable at pH 5-10. Rapidly inactivated at pH <3.0 or pH >11.0. (source: OIE technical disease card). Species involvedFor CSFV, only porcine species are involved (pig, swine, wild boar). Serological cross-reaction with ruminant pestiviruses Chronically and persistently infected (PI) animals may occur. Experimental transmission to ruminants and rabbits is possible. GAPS: Transmissibility of CSFV to ruminants – sheep, goat, cattle under field conditions. Longevity of PI piglets infected in utero is unclear. Comments NA Comments NA Infected pigs and wild boar are the only reservoirs in Europe. GAPS:
Description of infection & disease in natural hostsIngestion of virus, direct (oronasal, sperm) and indirect contact (orofecal, contaminated equipment, clothes, vehicles, rodents, uncooked meat products). Infected wild boar are risk factors for domestic pigs. GAPS:
Comments NA Fever and hemorrhagic disease with immunosuppression as leucocytes almost disappear. Moribund pigs may also suffer from CNS symptoms. Clinical signs are similar in wild boar, though rarely seen, as they hide. Febrile, multisystemic disease with extremely variable, age and virus dependent symptoms. Acute, chronic, and prenatal courses. Signs include gastrointestinal, respiratory, central nervous, and reproductive disorders (huddling, dullness, high fever, anorexia, erythema, cyanosis, petechiae, staggering, weakness, convulsions and poor reproductive performances, swollen lymph nodes, conjunctivitis). Secondary infections due to immunological impairment. GAPS: Host and virulence factors determining the clinical outcome of infection and manifestation of distinct symptoms. 2 to 12 days, mainly 3-8 days (Depends on virulence of strain and host factors). Depending on virulence of the infecting virus isolate, presence of other primary/secondary pathogens and age class of animals the case fatality rate (the number of clinically affected animals that die from the disease) of the acute form of CSF may reach 70 to 95 % especially in young animals. It may be lower in breeding sows and boars. Chronically and persistently infected animals will all ultimately die after variable time of being infected. GAP: Factors determining the mortality rate in host populations, in particular in wild boar. Chronically infected pigs and congenitally infected piglets (persistently infected animals) shed the virus for months. GAP: Period of virus shedding esp. in wild boar (survival of chronic/ persistently infected pigs). As a consequence of its destructive effects on the lymphoid system CSFV is known to be immunosuppressive. The virus causes depletion of T- and B-lymphocytes, lymphoid follicles disintegration, as well as a thymus and bone marrow atrophy. Not surprisingly, animals severely affected by the disease do not develop neutralizing antibody before 2-4 weeks. Since CSFV is noncytopathic in vitro, and surviving piglets infected early in gestation may show few, if any clinical signs or lesions beyond thymic atrophy it has been suspected that the serious lesions seen in vivo following acute infection were linked to immunopathological damages induced by a reaction of the host itself to the virus infection. A basis for this is the high affinity of CSFV for the immune system with infection of leukocytes, macrophages, endothelial cells and dendritic cells. For this infection, the viral Npro protein which inhibits the release of IFN-α and -β from macrophages, endothelial cells and conventional dendritic cells, is important. In vitro data also suggests that Npro inhibits apoptosis. However, the infection is associated with a high systemic IFN type I response as well as a local inflammatory cytokine responses within primary and secondary lymphoid tissue. While macrophages are involved in secretion of pro-inflammatory cytokines, plasmacytoid dendritic cells are the only cell type “resistant” to the effect of Npro and therefore able to produce large quantities of IFN-α. The latter represent a most prominent and early response, and likely to represent a key event in immunopathogenesis. It is proposed that lymphopenia, destruction of lymphoid structures and leukocyte apoptosis is a consequence of a virus-induced “cytokine storm”. Also the changes in the haemostatic balance typical for the disease, inducing thrombocytopenia and disseminated haemorrhages, are thought to be triggered by overproduction of pro-inflammatory and antiviral factors. Virus-induced activation of endothelial cells could play a role in disease pathogenesis, by production of pro-coagulant factors and pro-inflammatory cytokines, as well as in facilitating virus dissemination by attracting monocytic cells. CSFV could also use dendritic cells as a vehicle to different sites in the body, especially to lymphoid tissues. GAPS: The viral elements of importance for pathogenesis are largely unknown and their identification will be critically important for a rational vaccine design as well to understand viral epidemiology considering the wide range of virulence. This suggests a spectrum of ineraction with the host response, exhibited to different degrees by different strains of the virus. To this end it is important to identify the viral factors (genes, protein elements, replication characteristics, cell tropism) that determine the virulence of a particular CSFV isolate. These are likely to determine the cell tropism and the capacity of the virus to replicate and persist in its primary target cells within the immune system. On the host side, it will be important to determine the sequence of events in immunopathogenesis and the role of individual cell types and their interaction to understand disease pathogenesis. To identify the cellular receptor(s) of CSFV will also be crucial to understand viral tropism. Zoonotic potentialNone. None. None. None. None. Impact on animal welfare and biodiversityClinical CSF is a severe welfare problem. However, animal welfare problems in farms are few given that the diagnosis is determined fast and the herd culled. In case of an outbreak severe welfare problems may arise among pigs in healthy farms in restriction zones, because of the imposed quarantine measures and transport stand stills. Long lasting courses are very bad for animal welfare with pneumonia, fever, lameness and wasting as the typical symptoms. GAPS:
No. Yes. Geographical distribution and spreadOccasionally outbreaks recurring in highly industrialised countries. Endemic in parts of Asia, Africa, Southern America, Eastern Europe, recurrent relapses in areas with infected wild boar. Supply a link to a good source of information. OIE Handistatus (http://www.oie.int/hs2/report.asp?lang=en) EU: Animal Disease Notification System (ADNS) (http://ec.europa.eu/food/animal/diseases/adns/index_en.htm) GAP: Information is not always up to date. Several countries do not report or no testing is performed, and the disease status therefore remains unknown. The disease is endemic in much of Asia, Central and South America, and parts of Europe and Africa. It was eradicated in the USA by 1978. Other regions free of CSF include Australia, Canada (1962), Ireland, New Zealand and Scandinavia. The virus is endemic in the wild boar population in parts of Europe. GAP: Continuous monitoring and overview of global CSF situation. Comments NA Numerous studies have been conducted on spatial spread and dynamics in domestic pigs. It is greatly influenced by human activities such as transport and pig density. GAP: Speed of spatial spread of CSF in wild boar under varying conditions (geography, density of forest, local climate, density of wild boars, hunting activity…) International trade of pigs, wild boar crossing borders, legal and illegal import of infected meat, waste management, rendering, safe disposal and illegal swill feeding maybe the reasons for introduction of CSF into a free country. GAP: Impact of global trade, illegal swill feeding, waste management and travel on disease spread. Indirect transmission reduced due to higher temperatures in summer, cold and moist conditions support the survival and spread of virus (fall -> spring season). GAP: Influence of food availability and physical status of wild boar during harsh climatological conditions on the course of CSF epidemics. No. No. No. Route of TransmissionDirect and indirect contacts, movement and contact with infected pigs (domestic and backyard pigs as well as wild boar), feeding of contaminated swill. GAP: Routes of between herd transmission, Quantification of direct and indirect contacts between herds and chance of transmission related to specific contacts. Mechanical vectors (vehicles and implements), persons, semen, (aerosols). GAP: Role of airborne transmission within and between herds. Late diagnosis and reporting, non appropriate control and eradication measures, poor hygiene and bad management, high pig density within holding or geographical region, dense wild boar population. Close contact between domestic pigs and wild boars. Detection and Immune response to infectionImmunosuppressive disease, in severe cases the animals die before seroconversion. Pigs infected with less virulent strains recover and as antibody positive they are protected of recurring infections, also from highly virulent CSFV strains. Reconvalescent animals develop neutralising antibodies with long-lasting solid protection. Chronically and persistently infected pigs fail to develop an effective immune response. Infection with CSFV leads to leukopenia and thrombocytopenia through mainly apoptotic pathways and thus depresses the immune system. GAP: Role of cellular immunity and mechanisms of immune suppression. Antibodies against the virus are used for diagnostic tests (ELISA, VNT). GAP: Currently, the ability to differentiate antibody to CSF from ruminant Pestivirus is complex, time consuming and can be unreliable, particularly at individual animal level. Main means of prevention, detection and control
GAPS:
Diagnostic Manual 2002/106/EC Technical Annex - OIE-Manual of Diagnostic tests and Vaccines, 2008. Organism Detection Tests:
Immunoassay Tests:
Nucleic Acid Detection Tests:
GAPS:
Vaccination with modified live virus strains is effective and safe in preventing losses and eradication of the disease provided that accompanying control measures are taken. In countries which are free of disease, or where eradication is in progress, vaccination is usually prohibited. Two relevant types of CSFV-vaccines are available: live attenuated (modified live vaccines = MLV) and E2 subunit (marker or DIVA) vaccines (E2subV). While the MLV are licensed or authorised by national authorities, E2SubV was registered by the EMEA. For the moment there is one E2subV commercially available. At present its licence has been temporarily withdrawn due to reduced shelf life. According to the directive marker vaccines could be used for emergency vaccination to live, i.e. free marketing of products of marker-vaccinated animals. However, this option has never been used so far. Emerging evidence from Asia that PRRSV infection reduces or negates efficacy of CSF vaccination. GAPS:
Treatment is neither allowed nor possible. Affected pigs must be slaughtered and the carcasses buried or destroyed in rendering plants. GAPS: Role and potential of antivirals in combination with vaccination in order to bridge the time after vaccination before antibodies rise, compatibility with legislation. In terms of Biosecurity: security clearance for staff and electronic authorisation systems entry to the laboratory. In terms of Biosafety in laboratories: The minimal levels for working with CSFV in the laboratory are laid down in the “Diagnostic Manual establishing diagnostic procedures, sampling methods and criteria for evaluation of laboratory tests for the confirmation of classical swine fever” (Commission Decision 2002/106/EC, Chapter IX). Any laboratory working with CSFV has to have dedicated rooms for the work with CSFV. Dedicated outer clothing and disposable gloves must be worn and entry to the laboratory is limited to named and trained personnel only. Biological safety cabinets (class I or II), which should have double HEPA filtration of exhaust air, must be used for all manipulations of live virus. All equipment used for diagnosis must be available within the CSF unit. It is obligatory to keep CSF virus in secure storage. All ampoules must be clearly labelled and comprehensive records must be maintained. Personnel must wash and disinfect hands before leaving the unit, and the outer laboratory clothing must be sterilised before removal from the unit. Personnel are not permitted near pigs for 48 hours after leaving the unit. If extensive multiplication of virus is performed or in case of large animal experiments within the unit, additional requirements (e.g. complete change of clothes on entry, double HEPA filtration of exhaust air) need to be applied. Additional safety measures for the work with CSFV are also laid down by national legislation of the Member States. GAP: There is no international common legal basis for minimum requirements for biosafety measures in pig holdings, individual regulations in each country. In case of outbreaks designation of infected zone, with control of pig movements. Import of infected pigs and meat is prohibited; similar rule apply for personal consumable goods of international travelers. GAPS:
GAP: Prohibition of swill feeding is not fully enforced in certain countries (conflict of prohibition of swill feeding with sustainable pig husbandry).
GAPS:
Several large outbreaks in Member States since 1990. 1997 outbreak in The Netherlands in an area with high pig density, controlled and finally eradicated without resorting to vaccination after 14 month. In The Netherlands 1997: 11 Mio pigs were killed and destroyed also for animal welfare reasons, costs of 2 Billion US$. GAP: There is a need for a EU harmonized format/framework for the cost estimation, to enable transparent comparison of the economic impact (1) of different control strategies, and (2) between EU member states. Disease information from the OIEYes. http://www.oie.int/fileadmin/Home/eng/Media_Center/docs/pdf/Disease_cards/CSF-EN.pdf http://www.oie.int/index.php?id=169&L=0&htmfile=chapitre_1.15.2.htm http://www.oie.int/fileadmin/Home/eng/Health_standards/tahm/2.08.03_CSF.pdf Socio-economic impactNot applicable. Not applicable.
GAP: Compensation schemes are not emphasizing preventive measures.
GAP: More information needed in particular for new live marker vaccines or for MLV with free marketing of meat (cfr EFSA opinion dec 2008). Loss of import and export markets: pigs and pork products. High economic impact especially in areas with high pig density and export rates. Due to movement and trade restrictions. Loss of genetically valuable animals, rare breeds. For countries with backyard pig production, can also impact on poor communities, where pigs are used to supplement income. GAPS: Evaluation of the cost of control measures e. g. in a tourist area:
Trade implicationsIn case of an outbreak quarantine measures and transport stand stills are imposed on infected areas. Once a region is declared free of CSFV trade may be resumed again. This usually takes a few months or longer. GAPS:
In case of an outbreak quarantine measures and transport stand stills are imposed on infected areas. Once a region is declared free of CSFV trade may be resumed again. This usually takes a few months or longer. GAPS:
In case of an outbreak quarantine measures and transport stand stills are imposed on infected areas. Once a region is declared free of CSFV trade may be resumed again. This usually takes a few months or longer. GAPS:
Main perceived obstacles for effective prevention and controlDifficulties in clinical diagnosis in domestic pigs due to variability of symptoms, coinciding with emergence of other diseases with similar clinical presentation (PDNS, PRRS), reluctance of veterinarians to include CSF in the list of differential diagnoses (due to severe consequences), lack of managerial skills and practice, endemically infected wild boar, lack of biosecurity, illegal swill feeding. Illegal import of meat from infected areas due to imperfect control measures on global trade. The occurrence of low virulent strains in recent years has made the diagnosis more problematic. Lack of awareness by farmers and veterinarians especially in countries free of the disease. Wild boar, difficult diagnosis in domestic pigs, materials for analysis obtained from already dead pigs, and illegal import of meat from infected areas. Traditional methods of dry-curing to produce local delicacies, also without need for refrigeration. Swill feeding of material originating from wild boar. GAPS:
Main perceived facilitators for effective prevention and control
GAPS:
RiskDue to e.g. increased world-wide traffic, intensified trade contacts and tourism the risk of (re-)introduction of the disease has increased. Spread of disease might also be facilitated by intensified contacts and the factors mentioned above. Endemic CSF in wild boar threatens the domestic pig population of the country of origin and neighbouring countries. Introduction of CSF in a disease-free country has a disastrous effect on the pig industry and the economy. Main critical gaps
ConclusionCSF remains a major health and trade problem for the pig industry. In endemic countries or those with a wild boar reservoir, CSF remains a priority for Veterinary Services. Surveillance as well as stamping out and/or vaccination remain principle tools of prevention and control, depending on the context. A number of vaccines and diagnostic tests are available in Europe and worldwide. Technological advancement in both domains would be desirable. Due to a relatively high number of fairly performing diagnostic tools and vaccines on the market, it is unlikely that the industry will invest in new technologies, unless external funding sources can be mobilized within the context of formal research and development networks. |
