REFERENCE LABORATORY REVIEWING SOME KEY POINTS, GAPS AND NEEDS FOR PREVENTION, CONTROL AND ERADICATION OF AFRICAN SWINE FEVER

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1 REFERENCE LABORATORY S REVIEWING SOME KEY POINTS, GAPS AND NEEDS FOR PREVENTION, CONTROL AND ERADICATION OF AFRICAN SWINE FEVER

2 CONTENT AFRICAN SWINE FEVER Main Characteristics Susceptible species. Clinical picture. Transmission routes Epidemiology Diagnosis TO REMIND GAPs and Needs concerning Early Detection. Control /eradication strategies. Key points. Some Needs in Europe

3 MAIN CHARACTERISTICS - Haemorrhagic disease of swine, caused by a large complex virus, High economic Impact - High mortality rates associated with acute and peracute forms - Incubation period range: 4-19 days. belonging to the former OIE List A

4 Virus isolates vary in pathogenicity - high and low virulence forms African swine fever TO KEEP IN MIND Incubation period: -Natural infection: 4-19 days -Experimental infection: 2-5 days Virulence Virulence Clinical course Clinical course High virulence High virulence days 77days Moderate virulence 7-20 days 7-20 days Moderate virulence Low virulence Low virulence source: 1 month 1 month Mortality Mortality % % 20-40% adults 20-40% adults 70-80% young animals 70-80% young animals 30% (pregnant sows, 30% (pregnant young animals, pigs with sows, concurrent diseases) young animals, pigs with concurrent diseases) Univ. Córdoba (UCO) and ((OIE-WRL Fac. Vet. Madrid, UCM, Spain.

5 AFRICAN SWINE FEVER VIRUS (ASFV) Very complex large virus, big size, large genome: kb. Encodes about 150 ORFs. Genetic variability Replication in macrophages NO neutralizing antibodies vp73 Vp32& nm More than 100 structural and infection proteins 22 genotypes (VP72) Very resistant to inactivation in Environment In Africa: All. In Europe, I,II. vp54

6 Very complex and large genome ASF VIRUS GENOME Kbp. Encodes about 150 ORFs. Genome variability mainly due to deletions and insertions LVR and RVR Conserved Central Region - Encodes 5 Multigene families -Large length variations between 3-20 kb, Due to deletion and insertions of complete genes GENETIC CHARACTERIZATION OF SPECIFIC SEQUENCES ONLY METHOD TO ESTABLISH RELATIONSHIPS AMONG DIFFERENT ASFV ISOLATES

7 MAIN CHARACTERISTICS AFRICAN SWINE FEVER PROTECTION NO VACCINE AVAILABLE All attempts has failed: Classical designs, inactivated, attenuated (partial protection), recombinant vaccines, DNA vaccines,. ASFV not induces neutralizing Antibodies,though they play some type of protection, as well as in chronic and endemic ASF infection.

8 ASF only affects PORCINE SPECIES Both wild host and domestic NO ZOONOTIC DISEASE. Domestic pigs and European wild boars are very susceptible to infection, showing clinical symptoms.animals surviving to infection could become into asynthomatic carriers.

9 ASF only affects PORCINE SPECIES Both wild host and domestic NO ZOONOTIC DISEASE. Domestic pigs and European wild boars are very susceptible to infection, showing clinical symptoms. Animals surviving to infection could become into asynthomatic carriers. Wildsuids in Africa are persistently infected for long periods with no disease signs.

10 ASF only affects PORCINE SPECIES Both wild host and domestic NO ZOONOTIC DISEASE. Domestic pigs and European wild boars are very susceptible to infection, showing clinical symptoms.animals surviving to infection could become into asynthomatic carriers. Wildsuids in Africa are persistently infected for long periods with no disease signs. Soft ticks of the Ornithodoros species, O.erraticus (Europe) and O.moubata (Africa) acts as reservoirs and transmission vectors of ASFV.

11 BIOLOGICAL VECTOR: Soft ticks. Ornithodoros genus EUROPE: O. ERRATICUS: NO TRANSOVARIAL TRANSMISSION VIRUS: 3-5 YEARS The Natural History Museum, London AFRICA: O. MOUBATA TRANSOVARIAL (5 ninphe stages) Others: O. Sonrai, O. Porcinus, O. Verrucosus, etc. All O. tested are susceptible to ASF Virus

12 ASF CHARACTERISTICS CARRIER ANIMALS European Wild Boar WB exhibits a similar clinical picture to Domestic pigs Domestic pigs BOTH COULD BECOME CHRONIC, ACTING AS CARRIERS African Wild Suids Innaparent Infection Low viraemia Persistently Infected

13 Clinical picture: Fever, anorexia, lethargy, postration, diahrrea, conjuntivitis, sudden deaths, Pathology, gross lessions: haemorhrrages in organs,..

14 Clinical Signs may resemble other haemohrragic diseases. Easily Confused with: Classical Swine Fever Erisipelas Salmonellosis Other Septicaemic conditions PDNS Differential laboratory diagnosis is needed

15 MAIN ROUTES FOR TRANSMISSION INTO FREE AREAS: By eating infected swill or garbages By direct contact between sick or carrier and healthy animals Domestic and wilds (exudates, wounds,...)

16 2. Movement of pork or pig product: 3. Movements of infected wild boars: Russia, 2007 Lithuania 2014 Poland, Raw pork waste at airport/port: Portugal, 1960 Spain 1960 Italy, 1983 Belgium, 1985 Lisbon 1957 Malta, 1978 Sardinia, 1978 Georgia, 2007 Source, Sánchez-Vizcaíno, UCM, OIE WRL

17 MAIN ROUTES FOR TRANSMISSION ONCE ESTABLISHED: INFECTED OR CARRIERS PIGS (D&W) play an important role in the dissemination of the disease Ticks, and backyard To be a major consideration in designing strategies for ASF eradication Contaminated transport, FOOD slurry, insects, rats...

18 1. Movements of infected pigs or carriers from infected neighbouring countries: Nigeria, Togo, Benin, all in ; Zambia, 2001; Kenya 2001; Ghana 2002;Tanzania 2004;Burkina Faso 2007;Kenya 2007;Tanzania Boar or pork meat of infected swine fed to pigs (movement of infected meat): South Africa 1973; Sao Tome&Principe, 1979; Ivory Coast 1996; Namibia 2004; Kenya 2007 Source, Sánchez-Vizcaíno, UCM, OIE WRL

19 Ranking of matrixes according to their ability to contain and maintain infectious ASFV.Based on Expert Elicitation Wild boar (transported) Domestic pigs (transported) Frozen meat Smoked meat Any vehicles-contaminated outside Professional or hobby in pig/wild boar sector and their instruments/equipment Animal feed Litter Fomites Ticks Chilled meat Skin fat Salted, dried/fermented meat Vehicles for animal transportcontaminated inside Slurry Non- professional in pig sector (e.g. tourists business, family ) Pests (rodents)

20 EPIDEMIOLOGY. HISTORY. Portugal, 1957, Spain, France, 1964, Italy, 1967,69,93 Malta, 1978, Belgium, 1985, Netherlands, 1986 Lisbon1957 ERADICATED Cuba (1971,80) Haiti (1978) 1921, Kenya Cuba, 1971, 1980 Brasil, 1978 Dom. R., 1978, Haití, 1979 Brasil (1978) Eradicated in the Iberian Peninsula, 1995

21 ASF distribution in Africa Endemic Senegal Gambia Guinée Bissau Burkina Faso Togo Benin Nigeria Cameroon Congo Brazaville Angola, Cabo Verde RDC Uganda Rwanda Burundi Kenya Tanzania Mozambique Namibia Madagascar From 2004, A SIGNIFICANT INCREASE OF OUTBREAKS SOURCE: World Organization for Animal Health (OIE)

22 ASF Current situation AFRICAN SWINE FEVER 2007-JAN 2014 Endemic since 1978 in Sardinia (Italy) Endemic in more than 20 Subsaharan African countries Since 2007 Veterinary Services and NRLs of EU Countries have been deeply working in their Contingency Plans for ASF Laboratory capacity and prevention /control measures. From 2007, Continuing spreading into eastern europe. RF going to endimicity. to adjust

23 THE 22 GENOTYPES PRESENT IN AFRICA 1957 Angola: genotype I to Lisbon, spreading Europe and c/s Am. Li s Cuba 1971, 1980 b Dom. Rep 1978 o Haiti 1978 n 195 7, 60 Brasil 1978 Related ASF-West Africa viruses ASF GENOTYPES 22 GENOTYPES DESCRIBED TO DATE, Based on P72 FRAGMENT molecular characterization Georgia June 2007

24 World Organization for Animal Health (OIE)

25 UPDATE ASF IN EU Lithuania and Poland (2014) GENOTYPE II No evidence of genetic variations in p72, p54 and B602L genes between ASFV isolates has been revealed so far.

26 In vivo STUDIES. BIOLOGICAL CHARACTERIZATION REPRODUCTION OF THE DISEASE. Azerbaijan: Az08D Armenia: Arm 07 Ukraine: Ukr12/ZAPO Lithuania ON GOING VIRULENT STRAINS ACUTE FORM OF THE DISEASE HIGH MORTALITY: VERY DEPENDENT of the ROUTE, and DOSES. usually from 6-9dpi, in Domestic Pigs ANTIBODY RESPONSE: from second week of infection.

27 IN VIVO Experimental infection with Lithuania strain (4 inoculated +2 contacts) : MAIN CLINICAL SIGNS: -high body temperature (6/6). - ocular discharges (3/6), turn bluish-purple - hemorrhages on the ears (5/6) - hemorrhages in abdomen (1/6), - reddening of the skin (2/6) - bloody diarrhea (3/6). - Mild anorexia, lethargy, weakness and recumbence associated with the high fever. DIAGNOSIS: Virus easily detected by PCR in BLOOD and ORGANS, included BONE MARROW. Serology positive by IPT.

28 ASF SOME IMPORTANT POINTS Clinical signs similar to other diseases Laboratory diagnosis needed Domestic & Wild animals affected Ticks Carrier animals Summarizing PROBLEMS FOR ASF CONTROL No vaccine available 22 genotypes genotype II Freezer Very resistant in the environment Pigs and products

29 ASF DIAGNOSIS INFECTION DISEASE/DEAD CARRIERS Dinamic of ASF Infection VIRUS VIRUS AND ANTIBODIES ANTIBODIES DNA/Ag Detection Techniques DNA and antibody Detection Techniques 0 dpi CLINICAL SIGNS 7 dpi 35 dpi CARRIERS

30 Diagnosis of ASF ASF DIAGNOSIS: KEY POINTS Starting in the second week after the infection

31 TARGET SAMPLE FOR DIAGNOSIS WHOLE BLOOD SERA Filter CARDS, TICKS TISSUES Spleen Liver Lung Kidney Mediastinic L.N. Renal L.N. Retropharingeal L.N. BONE MARROW ALSO SUITABLE GOOD DIAGNOSIS REQUIRES GOOD SAMPLES

32 SUMARIZING AVAILABLE DIAGNOSTIC TESTS Antibody Detection Techniques ELISA K3* ELISA OIE ELISA ID-VET* ELISA-Svanova* Ab PENSIDE test* Confirmatory tests: IB TEST IPT TEST IFA TEST * COMMERCIAL KITS Virus Detection Techniques Virus Isolation/HAD FAT (DIF) TEST Antigen ELISA K2* PCR Conventional-Aguero Real timepcr-king UPL PCR PCR Multiplex PCR Tignon PCR Tetracore * Tetracore/ARS Isothermal tests (Not Validated)

33 ASF PREVENTION AND CONTROL - VERY COMPLEX DISEASE. - NOT VACCINE AVAILABLE. - CONTROL OF THE DISEASE IS MAINLY BASED ON EARLY DETECTION AND STRICT SANITARY MEASURES - Recognition of the disease in the field Diferential Laboratory Diagnosis LABORATORY DIAGNOSIS IS ESSENTIAL FOR THE CONTROL OF ASF (THOUGH NOT ENOUGH)

34 REMINDING SOME IMPORTANT POINTS FOR AN EARLY DETECTION. RISK FACTORS No perception of the risk for entrance: - No good information to farmers and Vets Movements of Legal and ilegal imports of live pigs and meat products Commercial Trade with affected countries, etc Wrong surveillance Programme

35 REMINDING SOME IMPORTANT POINTS FOR AN EARLY DETECTION. RISK FACTORS Low biosecurity practices Swill feeding Backyard systems Late Detection in the field due to not enough information on ASF of farmers and veterinarians. How is ASF? POLAND: THOUSANDS VETS TRAINED.

36 REMINDING SOME IMPORTANT POINTS FOR AN EARLY DETECTION. RISK FACTORS LOW PRESENCE OF VETERINARY SERVICE IN THE AREA Poor communication system of a clinical suspicion Deficient differential clinical diagnosis in the field Inadecuate conexión field-laboratory i

37 REMINDING SOME IMPORTANT POINTS FOR AN EARLY DETECTION. RISK FACTORS INADEQUATE CONTROL PROGRAM: Movement of animals and products WITHOUT CONTROL Swill feeding. Difficult to changes mentality Not establish the control and surveillance area Delayed compensation + lack of resources PIG PRODUCTION SYSTEM: i Pig density Farming practices (backyard, swill feeding!!) PRESENCE OF WILD BOARS in contact with domestic pigs PRESENCE OF TICKS

38 CONTROL/ERADICATION STRATEGIES. Key Actions RESOURCES, funds and Personnel, LAW IN PLACE. GOOD PROGRAMME prepared within all ACTORS, taking into account the SPECIFIC SCENARIO

39 ASF. Scenarios : EASTERN EUROPE Domestic pigs + Wildboar + Backyard envolvement WB limit: 10 animals /km 2 Higher: endemicity of the disease Lower: no own circulation mantain by contact with domestic animals Estimation of wild boar density will provide info to understand their role in the epidemiology.

40 CONTROL/ERADICATION STRATEGIES. Key Actions RESOURCES, funds and Personnel, LAW IN PLACE. GOOD PROGRAMME prepared within all ACTORS, taking into account the SPECIFIC SCENARIO. COMPENSATION Immediate and Adequate compensation to the pig producers

41 CONTROL/ERADICATION STRATEGIES. Key Actions NOTIFICATION SYSTEM ZONING OF AFFECTED AREAS CONTROL OF MOVEMENT. IDENTIFICATION. LABORATORY CONFIRMATION. Detection of positives and carriers animals ELIMINATION OF ALL POSITIVES i AND CARRIERS ANIMALS PROCEDURE FOR DESTRUCTIONS OF CARCASSES DEPOPULATION CLEANING AND DISINFECTION SENTINEL ANIMALS REPOPULATION

42 CONTROL STRATEGIES. Key Actions NETWORK OF MOBILE VETS FIELD TEAMS Sanitary control of holdings Animal identification Epidemiological surveys Samples collection virological and Serological control at abattoirs Epidemiological investigations Promoting Sanitary Associations

43 CONTROL STRATEGIES. Key Actions IMPROVEMENT OF ANIMAL HOLDINGS - To improve sanitary barriers to prevent de spread of the disease - Hygiene measures: fences, sanitary enclosures, safe disposal of manure i For this purpose: Loans at low interest rate

44 Procedures once outbreak identified : Sanitary zone of a few hundred km radius Movement of animals, products, feed and waste into or out the sanitary zone were restricted Movement of people to and from the area were restricted After implementation measures were gradually lifted (although some specific were maintainedat least 3 months)

45 Livestock Movement & Animal Identification Movement of animals Vehicles required to be washed and disinfected Animals in transit previously identified & provided with veterinary certificate (stating origin & sanitary situation) Abattoir Vets checking the sanitary certificate (before slaughtering) Life pigs inspected antemortem & tissues posmortem Sanitary certificates retained at least 1 year Manufacturers retained identification of meat origin

46 Livestock Movement & Animal Identification Register & Identification Pig farmer census was improved & completed Producers & manufacturers register was improved Infected farms register was daily updated Annual Report of the Program development issued

47 Livestock Movement & Animal Identification Involvement and participation of farmers Wide publicity campaign in the mass media Encouraging the creation of Health Protection Group Lidership role in the eradication program (voluntary) Common approach against ASF Diagnostic l surveillance of breeders Correct sanitary infrastructures Sanitary suitable program for ASF Aids from Administration 1990: 1,000 HPG created grouping 41,500 farmers & 1million animals A register was created classifying farms (health status & facilities)

48 Regionalization

49 FROM OUR EXPERIENCE, WE HAVE LEARNED: EPIDEMIOLOGY LABORATORY DIAGNOSIS A GOOD DIAGNOSIS OF ASF IS ESSENTIAL FOR THE CONTROL OF ASF, BUT NOT ENOUGH, INFORMATION for implementing GOOD ASF CONTROL ESTRATEGIES is needed to get ERADICATION

50 REVIEW ASF CONTINGENCY PLANS It should include the strategy, organization structure, ASF information and resources needed for rapid efficient deployment of human and material resources and those resources required to be maintained during different situations. ADMINISTRATIVE STRUCTURE: Veterinary Services Legislation, diagnosis methodology, etc. LIVESTOCK PRODUCTION STRUCTURE: Census, farm COORDINATION OF ACTIONS Location, movements, wild live population. ASF DISEASE CHARACTERISTICS: Risk factors, susceptible animals, Vectors, clinical sings, lesions, samples to labs, route of entrance, diagnosis methods, desinfectants,..

51 SOME NEEDS IN EUROPE IMPROVE EXPERTISE EDUCATION: Be ready to detect the clinical picture FIELD SIMULATIONS Training of veterinarians to raise awareness TRAINING and TECHNOLOGY TRANSFER at NRLs and at Province/District laboratories, Periodic training of laboratory staff

52 SOME NEEDS IN AFFECTED REGIONS - TO CONTINUE IMPROVING KNOWLEDGE ON ASF EPIDEMIOLOGY i.e. Increase knowledge of the epidemiological situation in eastern Europe, carrier state, role of wild boars, -IDENTIFICATION OF RISK FACTORS FOR ASF INTRODUCTION AND SPREADING. i.e: In affected regions of Europe: map of pig density, Maps of WB distribution and ticks, etc) - MAPs for RISK ASSESSMENT

53 ASFORCE EU New Project EU Development of a generic Risk Assessment Framework for the introduction of ASF into EU CISA-INIA UCM RCV

54 OBJETIVE: to provide a flexible and useful Tool that will allow the EU State Members to Estimate their Own Risk for ASFV Introduction. RESULTS A General Framework for Risk Assessment In a Single Excell Being Constructed in the Easiest Way Every Country Will Be Able to Introduce their Own Data. Possibility to be extrapolated to other Regions

55 MORE RESEARCH ON AFRICAN SWINE FEVER DIAGNOSIS New Diagnostic tests adapted to scenarios, including penside tests Improve Validation of existing tests with different type of samples, Increase genome sequencing, additional regions, and full genome sequencing.. DIVA Vaccine

56 IT IS THE TIME TO BE READY

57 THANK YOU NVRI, PULAWY THANK YOU POLAND THANK YOU FOR YOUR ATENTION EU and FAO REFERENCE LABORATORIES AND ASF EPIDEMIOLOGY GROUP AT CISA-INIA