Presented by José M. Sánchez-Vizcaíno at the African Swine Fever Diagnostics, Surveillance, Epidemiology and Control Workshop, Nairobi, Kenya, 20-21 July 2011

1. ASF: GLOBAL IMPACT AND
CONTROL
ASF REFERENCE LABORATORY
Prof. José M. Sánchez- Vizcaíno
jmvizcaino@visavet.ucm.es
www.sanidadanimal.info

2. ASFV: A old friend 1978-
MAIN WORK:
DIAGNOSIS TEST &
REAGENTS
ASF REFERENCE LABORATORY EPIDEMIOLOGY-CONTROL
and ERADICATION

3. AGENDA:
ASF. A REEMERGING DISEASE
EPIDEMIOLOGICAL SITUATION
CRITICAL POINTS FOR CONTROL
ASF VACCINE
ASF FUTURE
CONCLUTIONS

4. ASF. Routes of transmission
FREE AREAS:
By eating infected swill or garbages
By direct contact between sick or carrier and healthy animals (exudates, wounds,...)
ONCE ESTABLISHED:
INFECTED OR CARRIERS PIGS (D&W) play an important role in the dissemination of the disease
Contaminated transport, FOOD
Ticks and back yard
slurry, insects, rats...

5. 1. Raw pork waste at airport/port:
Lisbon 1957
Malta, 1978
Sardinia, 1978
Georgia, 2007
2. Movement of pork or pig products: Portugal, 1960
Spain 1960
Italy, 1983
Belgium, 1985
Russia, 2008-
3. Movements of infected wild boars:
Russia, 2008-

6. 1. Movements of infected pigs or carriers from
infected neighbouring countries
Nigeria, Togo, Benin, all in 1997-98;
Zambia, 2001; Kenya 2001;
Ghana 2002;Tanzania 2004;
Burkina Faso 2007;Kenya 2007;
Tanzania 2008
2. 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

7. ASF EPIDEMIOLOGY: Historical distribution I
1957
Portugal, 1957
Kenya1921 Spain 1960
Frane 1974
Malta 1978
Sardinia 1978
Italy, 1983
Belgium, 1985
Russia, 2008-

8. ASF. Scenarios : Europe I
Spain 1985-1995
IN DOOR

10. ASF. Scenarios : Europe II
Sardinia,Italy PARTICULAR FARMES
Backyard (16,031) : 90.34%
Intensive (320): 1,80%
Confined/Fr (899): 5.06%
Free ranging (494).: 2.78%
NO SOFT TICKS in Sardinia
1993-2003 (37)
2004-2005 (38)
1993-2005 (20)
Pig population.: 248.356
Epidemic weaves:94-96; 2004-2005.
Source of info.: NRL for ASF meeting , 2006, D. Rutili

11. ASF EPIDEMIOLOGY: Historical distribution II
1978

12. ASF.Scenarios :Central and S.America
• CUBA 1978
• D. REPUBLIC 1978
•BRASIL 1980
BACKYARD
NO TICK

13. ASF EPIDEMIOLOGY: Historical distribution
2007
1998 2001

14. ASF. A REMERGING DISEASE

15. ASF.Scenarios: South and East Africa
Positive Virus. No
Abs. Tolerance pigs
????
Sylvatic cycle 21 Genotypes
D+D+T
DOMESTIC INFECTED PIGS NO Ab ?

16. ASF. Scenarios : West Africa
back yard
D to D
W to D
Role of Ticks ??

17. 2007
Asfv, genotype II
Mozambique, Madagascar, Zambia
273 Outbreaks. More 78.000 Dead pigs
ASF 2007-2011

18. ASF EPIDEMIOLOGY:
4 affected countries
273 notified outbreaks
+78.000 dead pigs
Source: OIE, own elaboration

19. ASF in Russian Federation
• April 2007ASFV p72 genotype II, compatible
with the virus circulating in Mozambique,
Madagascar and Zambia (Rowlands et al., 2008)
• All the ASFV isolates identical p72, p54 and CVR
sequences  suggesting only one entry (Gallardo et
al., 2009)
• No pathological changes  Acute and hiperacute
forms of the disease (Blagodarsnosti, 2011) .
• No serological (Ab) surveillance has been made

20. ASF. Scenarios : Europe III
D + W + BY
D to D
Back yard pigs
Risk of Endemicity
Chronic form ?

21. WHY IS ASF MOVING?
World globalization More ASF virus in Africa
Economic crisis Swill feeding

22. IDENTIFICATION OF RISK FACTORS
ENTRANCE IN CAUCASUS REGION:
 Increase of the ASF V in Africa
 Economic crisis
 Swill feeding
 Lack of biosecurity
SPREAD:
 Swill feeding!! TRADITION
 Wild boars contact with domestic
 No biosecurity (ASF don’t need high biosecurity)
 Movement of animals and products WITHOUT CONTROL
 No a Coordinated National control program (Local Program
Krasnodar Region)
ENDEMICITY:
 Wild boar affected
 Swill feeding
 Potential. Carriers and chronic infections
 NO COORDINATED NATIONAL PROGRAM. NO COMPESATION
FOR FARMES
 Vector (ticks)?

23. POSIBLE ENTRANCE: MODERATE Efsa,2010

24. http://www.efsa.europa.eu/en/scdocs/scdoc/1556.htm

25. CONCLUSIONS AND
RECOMMENDATIONS
ASF in the Caucasus and Russian Federation
• The ASFV circulating in the Caucasus and the Russian Federation
is a highly virulent virus. No reduction of virulence since the first
outbreak in 2007 in Georgia.
• ASF has spread in the TCC and in the RF since 2007; measures put
in place were not sufficient to control the spread
• The risk of maintaining ASF and its spread within the TCC and the
RF in domestic pigs is HIGH
• The risk of ASF introduction into the EU is moderate
• Risk of ASF become endemic in domestic pigs in EU is negligible
(High Biosecurity), low or moderate (free range)

26. EVALUATING THE RISK OF ASFV ENTRANCE IN THE EU
Development of a generic CUANTITATIVE risk assessment
framework for the introduction of ASF in EU countries

27. ROUTES FOR ASFV INTRODUCTION IN THE UE
Live animals
(domestic+wild)
• Legal imports
Semen and embryo
Animal Products
• Illegal imports
Meat Products
• Wild animals
• Ticks: Ornithodorus spp.
• Fomits: vehicules, leftovers, people….

28. RA (stochastic) for the potential ASFV introduction into the UE
Pathway
Live pig Pathway
imports Wild boars
Suitable
areas for WB
Mur et al., 2011
De la Torre et al., 2011

29. LEGAL IMPORTS OF LIVE SWINES
The overall mean (95% PI) annual probability of ASFV introduction into the EU by
legal import of live pigs was 5.22*10-3 (6.06*10-4, 1.84*10-2 ) ~ one outbreak in
192 years.
69
%
68%

30. LEGAL IMPORTS OF PIG PRODUCTS EXTRA EU
OTHER
3%
FRESH
30%
FROZEN
67%

31. VEHICULES/ROADS
SEMIQUANTITATIVE
MODEL

32. SOME ASF CHARACTERISTICS

33. AFRICAN SWINE FEVER IMPORTANCES POINTS
No neutralizing Ab
Pigs &products
No vaccine available
Domestic & Wild High variability
animals affected
PROBLEMS FOR
ASF CONTROL Ticks
Carrier animals Freezer
Clinical signs similar to
other diseases Laboratory diagnosis
needed
Very resistant in
the environment

34. ASF LABORATORY DIAGNOSIS
1 2 3 4 5 6 7 8 9 10 11 12 13 14 C M V
257 bp-
108 bp-
PPC-3/4 + PPA-1/2
GOOD HEALTH

35. ASF PROTECTION: NO VACCINE
• NO INACTIVATED VACCINE
• ATENUATED VACCINE. NO SAFE AND ONLY PARTIAL
PROTECTION in HOMOLOGOUS (CARRIERS & C. FORM)
• NO RECOMBINAT VACCINE: NO good candidates
ANTIBODIES ARE RELATED WITH SOME
•NO DNA: TYPE OF PROTECTION
Some AS WELL AS WITH
Candidates CHRONIC AND ENDEMIC ASF INFECTION
Eradication without vaccine is
•NO SubUnit vaccines: very poor partial protection
possible but not easy.
Endemics:Portugal,Spain.
No Endemics countries: Brazil…

36. ASF. Spain: 1985-1995
IN DOOR
OUT DOOR

37. ASF IMMUNE RESPONSES INVOLVED IN PROTECTION
POOR UNDERSTOOD:
• PROTECTIVE IMMUNITY AGAINST HOMOLOGOUS VIRUS
(VIRUS IN LINPHO NODES)
• THE MAIN DIFFICULTY. LACK OF NEUTRALIZING Ab and
high genetic variability
• Ab PARTIAL PROTECTION. DELAY IN THE ONSET C. SIGNS
• IMPORTANCE ROLE OF NK AND CD 8. DESTROYED I. M
• SOME TYPE OF PROTECCION (Ab and CMI) OCCURS

38. PROBLEMS OF ATENUATED ASF VACCINE UNTIL NOW:
LIMITED FIELD STUDIES: PORTUGAL and SPAIN 60s-70s
EXPERIMENTAL RESULTS: SEVERAL AUTHORS
A) Release of infected virus: Low virulence strains, Chronic
forms ?. Carriers (Portugal, Spain 70s )
B) No sufficiently attenuated
C) Only Homologous virus protection.

39. PROSPECTS FOR ASF VACCINE:
Know more about Mechanism of Atenuated vaccine:
a)Pre Virus Entry (neutralizing Ab, Others)
b)Post Virus Entry (Infections inhibition)
1) Low virulence isolates by passages in TC or from field
2) Generation ASFV recombinant without some genes*
3) Recombinat with several ASFV genes in DNA vector
4) Others
* Several candidates look promesing

40. EARLY DETECTION
CONTROL AND ERADICATION
THE CHALLENGE

41. FIELD IS THE FIRST STEP:
COLLABORATION: ADMINISTRATION- FARMERS

42. RISK FACTORS for EARLY DETECTION I
• No perception of the risk for entrance:
No good information to farmers and Vets
– Legal and ilegal imports of live pigs and meat products
– Commercial relations with affected countries
– Other disases in the area (CSF, Erysipela…)
• Low education level, no information about the
disease to FAMERS and Vets
No information of ASF. How is ASF?
• Low biosecurity practices
– Swill feeding
– Backyard systems

43. RISK FACTORS for EARLY DETECTION II
• Late detection caused by:
– Wrong surveillance program. No RBS
– Late detection in field no formation of veterinary
services and farmers. Others diseases
– Low veterinary service in the area  inadequate
connection field-laboratory
– Unknown of the risk

44. FIELD TRAINING: FARMERS and VETS

45. INFORMATION TO FARMERS:

46. TV
RADIO
JOURNALS
CAFE

47. DIGITAL SIMULATION
http://rasve.mapa.es/Publica/Formacion/curso/index.html

48. ASF EARLY DETECTION NEEDED:
FIELD:
• Risk information
• ASF Information
LABs:
• Good conection with field
• Good test and procedure
TRAINING: FIELD AND LABORATORY

51. ASF CONTINGENCY PLANS. FAST RESPONCE:
ADMINISTRATIVE STRUCTURE: Veterinary Service
Legislation, diagnosis methodology, etc.
LIVESTOCK PRODUCTION STRUCTURE: Census, farms
Location, movements, wild live population….
ASF CHARACTERISTICS: Risks factors, susceptible animals
Vectors, clinical sings, lesions, samples to labs, route of
entrance, diagnosis methods, desinfectans, …..

53. Coordinated program
1. A program of all for all
2. Important farmers
3. Medium

55. RISK FACTORS for CONTROL
• 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:
– Pig density
– Farming practices (backyard, swill feeding!!)
• Presence of wild boars and contact with domestic pigs
• Presence of ticks

56. ASF. CONTROL AREA

57. MANUAL for a FAST RESPONCE
1. NOTIFICATION SYSTEM
2. ZONING OF AFECTED AREAS
3. BAN ON ANIMALS MOVEMENTS
4. LABORATORY CONFIRMATION
5. PROCEDURE FOR DESTRUCTIONS OF CARCASSES
6. DEPOPULATION
7. CLEANING AND DISINFECTION
8. SEROLOGICAL CONTROLS
9. STUDY WILD BOAR AND/OR VECTORS
10. SENTINEL ANIMALS
11. REPOPULATION

58. More ASFV in Africa
and now in CC and RF
Possibility of became
No vaccine available. endemic in some countries
Eradication without vaccine of Europe
not easy but possible
Moderate-high risk for the MORE TIME TO DETECT
EU countries INFECTION MORE
DIFFICULTES TO ERADICATE
ARE WE AWARE ?
ARE WE READY ?

59. IN MEMORIAN OF ISABEL MINGUEZ TUDELA
(08/05/1956- 16/04/2011)
Passed Away in Brussels at age of 54
Sencientic Officer in the DG Research
For over 15 years, she acted as a major
bridge within the scientific community
linking different European research teams
and establishing connections with scientists
from America, Asia and Africa. Manage a great
number of EU research projects on animal
health (ASFRisk)
Rest in Peace, dear friend
.

60. A W0RLD FREE of ASF
jmvizcaino@visavet.ucm.es