Presented by Marisa Arias at the African Swine Fever Diagnostics, Surveillance, Epidemiology and Control Workshop, Nairobi, Kenya, 20-21 July 2011

1. CENTRO DE INVESTIGACION EN
SANIDAD ANIMAL (CISA-INIA)
European Union Reference Laboratory for ASF (URL-ASF)
African swine fever (ASF) in Africa.
Main activities 2004-2011
Marisa Arias
Workshop on ASF, Nairobi, July, 2011

2. CISA (INIA)-ILRI Collaborative project
2004-2010
ASF Collaborative Project
“Development of new diagnostic assays and
epidemiological surveillance of viral pathogens of
livestock in Sub-Saharan Africa” between the
International Livestock Research Institute (ILRI) and
Centro de Investigacion En Sanidad Animal (CISA-
INIA)

3. CISA (INIA)- ASFRISK PROJECT
2008-2011

4. MAIN GOAL → Improvement of knowledge of the
epidemiological situation of ASF in Africa
Description of the
epidemiological INIA-ILRI
FAO
situation in African
countries based on
ASFRISK
epidemiological findings FAO INIA-ILRI
and samples collected in
different African
countries.

5. OBJECTIVES
To evaluate the epidemiological situation of ASF in Africa,
FROM THE MOLECULAR AND BIOLOGICAL POINT OF VIEW, to
characterize currently circulating field viruses of
epidemiological interest.
To develop, validate and apply improved, robust and/or
simple ANTIBODY AND NUCLEIC ACID DETECTION METHODS
FOR ASFV for the rapid detection and differential diagnosis
of suspected cases of ASF.
Technology Transfer to regional African Labs

6. WORK SCHEDULE
Sampling strategy → SAMPLING
COLLECTION in collaboration with the
Veterinary Services, Wildlife Services, OIE and
FAO
ASF diagnosis at CISA-INIA using OIE-
prescribed diagnostic tools.
ASFV genetic characterization
ASFV biological characterization

7. CISA (INIA)-ILRI Collaborative project
EAST AFRICA

8. CISA (INIA)-ILRI Collaborative project
WORK SCHEDULE
Sampling strategy → SAMPLING
COLLECTION in collaboration with the
Veterinary Services and Wildlife Services.
ASF diagnosis at CISA-INIA using OIE-
prescribed diagnostic tools.
ASFV genetic characterization
ASFV biological characterization

9. CISA (INIA)-ILRI Collaborative project
Phase I (2004-2007)→ ASF in East Africa (background)
Presence of the disease in Uganda. The
outbreak occurred in 2003 Uganda had
spread from the Central region to the of ASF in Kenya
The last outbreak Eastern
region of the country which shares a border Kenya
was reported in central
with Kenya (Busia(Kiambu, Nairobi and Thika) in
district).
August 2001.
Presence of the disease in Tanzania. Sporadic
outbreaks of the disease had been reported
in Northwest Tanzania since 2001.
ASF situation in 2004

10. CISA (INIA)-ILRI Collaborative project
ASF in KENYA (SAMPLING STRATEGY)
Surveillance program; Sampling collection from free-ranging pigs in
Western and Central Kenya (no apparent clinical signs related to ASF).

11. CISA (INIA)-ILRI Collaborative project
ASF in KENYA (SAMPLING STRATEGY)
Surveillance program; Sampling collection from free-ranging pigs
(no apparent clinical signs related to ASF) and bush pigs in Western
Kenya districts and in neighbouring Ruma National Park
Prevalence of ASFV
in bush pigs and their
role in the
transmission of the
disease.

12. CISA (INIA)-ILRI Collaborative project
Western Kenya districts and in neighbouring Ruma National Park
Study conducted since 2006 in 6 administrative divisions of Homabay district in Western Kenya to
identify critical issues related to pig production as well as risk factors for African swine fever. The
specific study area was selected because it represents a predominantly free-range
smallholder pig production system and lies in close proximity to a
national park, factors that increase the risk of ASF.

13. CISA (INIA)-ILRI Collaborative project
ASF in KENYA (SAMPLING STRATEGY)
Surveillance program; Sampling collection from warthogs and
ticks in Kapiti plain state (Central Kenya) in collaboration with
the KENYAN WILD LIFE SERVICE
Prevalence of ASFV in
warthogs (Phacochoerus
africanus ) and ticks and
the role in the
transmission of the
disease → SYLVATIC
CYCLE

14. CISA (INIA)-ILRI Collaborative project
ASF in KENYA (SAMPLING STRATEGY)
Surveillance program; Retrospective sampling collection from
warthogs in Northern Kenya from 2006-2008 in collaboration
with the KENYAN WILD LIFE SERVICE
Prevalence of
ASFV in warthogs
(Phacochoerus aethiopicus )
in Northern Kenya

15. CISA (INIA)-ILRI Collaborative project
ASF in KENYA (SAMPLING STRATEGY)
Kenyan Dept. Vet. Service, (Joseph Macharia)
Sampling collection from ASF outbreaks occurred in Kenya 2006-
2007 (OIE report 04/05/2007) and in 2010-2011 (OIE report 04/03/2011 )
2006-2007 2010-2011

16. CISA (INIA)-ILRI Collaborative project
ASF in UGANDA (SAMPLING STRATEGY)
→ Sampling collection from ASF outbreaks occurred in Uganda in 2007
Uganda, Ministry of Agriculture (Rose Ademun)
→ Sampling collection from National Parks in Western Uganda to determine
the prevalence of ASFV virus in warthogs and their role in the transmission of
the disease. In Collaboration with Conservation Tthrough Public Health
(CTPH)(Gladis)

17. CISA (INIA)-ILRI Collaborative project
ASF in TANZANIA (SAMPLING STRATEGY)
Surveillance program;
Sampling collection from
free-ranging pigs in North
and Eastern Tanzania were
last ASF outbreaks were
reported (no apparent clinical
signs related to ASF).
2005

18. CISA (INIA)-ILRI Collaborative project
ASF in TANZANIA (SAMPLING STRATEGY)
Collaboration with Tanzania Wild Life Service –TAWIRI-
→ Sampling collection in the Serengeti National Park to
determine the prevalence of ASFV virus in warthogs and their
role in the transmission of the disease.

19. CISA (INIA)-ASFRISK
WEST AFRICA
Sampling and characterisation
of currently circulating West
Africa field strains
Improve understanding
of virus spread and
maintenance in West
African countries

20. CISA (INIA)-ASFRISK
ASF in WEST AFRICA (SAMPLING STRATEGY)
2,446 samples from…. ASF free country → Côte d'Ivoire
2009
468 serum samples
(surveillance program)

21. CISA (INIA)-ASFRISK
ASF in WEST AFRICA (SAMPLING STRATEGY)
Study area and sampling collection
2,446 samples from…. ASFASF endemic country Burkina Faso
ASF endemic country → Ghana
endemic country → → Benin
ASF endemic country →Togo
20092009
2007-2009
2002-2008
261 samples (serum, tissue, whole blood)
31 samples (serum and tissues)
collected from 15 provinces out of 45 during
57collected from domesticand tissues) collected
31samplescollected fromduring ASF
tissues (serum pigs domestic
ASF outbreks
from domestic pigs during ASF outbreaks
ASF outbreaks
pigs during outbreak

22. CISA (INIA)-ASFRISK
ASF in WEST AFRICA (SAMPLING STRATEGY)
2,446 samples from…. ASF endemic country → Nigeria
2006-2008
1,598 samples (serum and tissues) collected
ASF outbreaks and
from domestic pigs during
endemic regions

23. CISA (INIA)-ASFRISK
ASF in WEST AFRICA (SAMPLING STRATEGY)
ASF endemic country → Republic of
the Congo

24. WORK SCHEDULE
Sampling strategy → SAMPLING COLLECTION in collaboration
with the Veterinary Services, Wildlife Services, OIE and FAO
ASF diagnosis at CISA-INIA using OIE-prescribed
diagnostic tools.
ASFV genetic characterization to determine;
Source of outbreaks
Role of sylvatic cycle in the transmission of ASF
ASFV biological characterization

25. WORK SCHEDULE
1. ASF infection status on samples collected.
1. Ab detection (ELISA+IB)
2. Virus detection (PCR + virus isolation)
2. ASF molecular characterization on selected positive
samples using ASF genotyping standarized
procedures
1. P72 genotyping (C-terminal end)
2. P54 genotyping (full gene)
3. CVR subtyping

26. MAIN FINDINGS → EAST AFRICA
Sylvatic cycle → endemically stable
Existence an
epidemiological situation involving domestic, wild pigs
(bushpigs and warthogs) and ticks.
Presence of ASF virus in absence of antibody response in healthy
domestic pigs in Central and Western Kenya.
Presence of ASF virus in absence of antibody response in bushpigs in
Western Kenya.
Presence of ASF virus and specific antibody response in warthogs and
ASFV in ticks in Kenya, Uganda and Tanzania.

27. MAIN FINDINGS → EAST AFRICA
ASF Coexistence directly from warthogs at same
in Kenya of
ASFVviruses genotyped in Kenya from ticks and domestic
isolates obtained
pigs collected in clustered within p72 genotypeASFand were
physical locality surveillance program without IX reported
outbreaks clustered in P72 genotype X → SYLVATICin for
distinct ASFV genotypes CYCLE
therefore genetically similar to viruses responsible
recentwarthog- burrow associated
disease outbreaks in East Africa (Kenya and Uganda).
ticks and in adult wild
warthogs and the apparent
transfer of both genotypes to
domestic pigs.

28. MAIN FINDINGS → EAST AFRICA
Presence of a domestic pig-associated genotype IX
causing ASF outbreaks in the border region between
Kenya and Uganda occurred in 2006 and 2007, 2010 and
2011.
•The rapid spread of the virus among pigs and the acute forms of the
disease suggest that the disease may have been maintained in the
border regions either in contaminated pork products, or live pigs that
became carrier-pigs, surviving the first outbreak.
•The evidence of trans-boundary transmission between these
countries indicates that a regional approach to disease control would be
more efficient.

29. MAIN FINDINGS → WEST AFRICA
The results obtained from the ASF
diagnosis on samples collected from
domestic pigs in target West African
countries confirms the evidence of a
high incidence of the disease in Ghana,
Benin, Burkina Faso, Togo, Nigeria and
Republic of Congo.

30. MAIN FINDINGS → WEST AFRICA
 Domestic pig-cycle
associated genotype I.
 Cross-virus circulation
between neighbouring
countries Togo, Ghana, Benin
and Nigeria in Maritime areas, as
well as in bordering areas among
Ghana and Burkina Faso.

31. MAIN FINDINGS → WEST AFRICA
P54 genotype Ic
P72 genotype I
West Congo districts → related historical West Africa viruses

32. MAIN FINDINGS → WEST AFRICA
P54 genotype IX
P72 genotype IX
Movement of a virus genotype previously associated with virulent ASF in eastern
Africa to western Africa, where the viruses have hitherto always been classified in p72
genotype I. there would be the possibility of future outbreaks of disease caused by novel
viruses in western Africa.districts → related continuingEast Africa viruses
East Congo This study confirms the recent spread of ASFV.

33. KENYA outbreaks 2006-2007
KENYA sylvatic cycle

34. UGANDA outbreaks 2007
Surveillance in Nigeria

35. Congo outbreaks 2009
African Swine Fever Virus p72 Genotype IX in
TITLE:
Domestic Pigs,Congo, 2009
Carmina Gallardo, Raquel Anchuelo,
Virginia Pelayo, Frédéric Poudevigne, Tati Leon,
Jacques Nzoussi, Richard Bishop,
Covadonga Pérez, Alejandro Soler, Raquel Nieto,
Hilario Martín, and Marisa Arias
Emerging Infectious Diseases • www.cdc.gov/eid • Vol. 17, No. 8, August 2011
DOI: 10.3201/eid1708.101877

36. WORK SCHEDULE
Sampling strategy → SAMPLING COLLECTION in
collaboration with the Veterinary Services, Wildlife
Services, OIE and FAO
ASF diagnostic at CISA-INIA using OIE-
prescribed diagnostic tools.
ASFV genetic characterization
ASFV biological characterization.

37. Clinical, biological and
immunological characteristics
of ASF recently investigated using
European pig breeds by
inoculation with three ASFV
Kenyan isolates belonging to
the most variable defined
genotypes IX and X.

38. MAIN FINDINGS
Acute to subacute forms of the disease showing typical
clinical signs and lesions associated to ASFV moderate strains.
Viremia detectable by OIE- prescribed virological diagnostic
techniques at early times post infection and was maintained
during the whole infection.
Antibody response detectable by OIE- prescribed
serological diagnostic techniques developed in the
second week of infection.

39. Complex epidemiological situation in eastern
regions of Africa
ASFRISK: Why Non evident ASF clinical signs in
ASF outbreaks, co-existing with a high viral
load and a significant lack of antibody
response
Increase of the risk of the endemicity of ASF and virus spreading
→ Increased difficulty for the control of the disease.

40. Existence Different Transmission cycles
ASFV genetic and antigenic variability
Are the current ASF diagnostic tools
adapted to all epidemiological situations?

41. The current ASF serological diagnostic
tools ARE ADAPTED TO ALL
EPIDEMIOLOGICAL SITUATIONS
The results obtained using new Ags based on current and variable circulating
ASFV strains were 100%according to those obtained using OIE prescribed
antibody detection techniques.

42. Immunogenetics and genetic characteristics of the
East Africa indigenous pig populations?

43. OBJECTIVE
Comparative in vivo study of the clinical,
pathological and immune response
against the ASFV infection in Kenyan
“indigenous pigs” and European
domestic pigs using Kenya ASFV strain.

44. EXPERIMENTAL DESIGN
Selected DOMESTIC PIG BREEDS
29 Indigenous domestic swine 10 Exotic domestic swine
(local breed) from Homa Bay (Landrace) from Kitengela
district (6-month old) (6-month old)

45. EXPERIMENTAL DESIGN
Selected DOMESTIC PIG LOCAL BREEDS
Homa Bay
Homa Bay district
(Western Kenya)
represents a
predominantly free-
range smallholder pig
production system
Selected ASFV isolate → Ken05/K2

46. PRELIMINARY CONCLUSIONS
 Different behaviour in ASFV infection, in ASF clinical signs.
 Delay of onset of ASF in “indigenous pigs”
 No external clinical signs related to ASF → the disease could
be easily unrecognized in field conditions. Several animals
even died without fever.
 High variety of pathological findings. Further investigation is
required .
 The laboratory was essential to confirm the presence of ASF
 Slight delay in the seroconversion in indigenous pigs.
March-May 2011. STUDIES ON GOING

47. COMPARATIVE RESULTS
Comparative Tª (average)

48. TECHNOLOGY TRANSFER
•Delivery of ASF reference reagents and Standard
operating procedures (SOP).
•Training courses on African Swine Fever (ASF)
diagnostic techniques in Africa → Transfer the ASF OIE-
prescribed diagnostic tools to participants from Department of
Veterinary Services (DVS) and National systems staff (regional labs) from
Eastern and Southern African countries and Nigeria.

49. European Union Reference Laboratory
2007-2011
TRANSFER OF TECHNOLOGY ON ASF diagnostic techniques
Mean: 10 days Training Course, on Diagnostic techniques
-Venue: Nigeria, Rwanda, Kenya
-(funds: INIA-ILRI)
-Venue: Uganda : 25 attendances from Vet
Services of Kenya, Tanzania and Uganda.
(funds: ASFRISK RTD,EC, INIA-ILRI)
-Venue: Tanzania, Tanzania, Kenya, Rwanda
and Uganda .30 attendances. (funds: ASFRISK
RTD,EC INIA-ILRI)

50. Collaboration in TRAINING Courses
ON ASF diagnostic techniques
5 days Training Course,
-Venue: OVI, Onderstepoort, South
Africa. May 2011.
DIAGNOSIS
- More than 20 delegates coming
from south and south East African
countries : Malawi, Botswana,
Angola, Zambia, Tanzania, Mauritius,
Seychelles, Mozambique, Swaziland,
Zimbawe, DR Congo, SouthAfrica.

51. MAIN CONCLUSIONS
• Complex epidemiological situation in eastern
regions of Africa with the presence of endemically
stable situation involving domestic, wild pigs and ticks
which difficult the control of the disease.
• Multiple genotypes in countries with the sylvatic cycle.
• Widespread of ASFV genotypes from eastern to
western Africa → evidence of trans-boundary
transmission between neighboring countries related to
movement of domestic pigs and pork products.

52. MAIN CONCLUSIONS
• Improvement of knowledge of epidemiology of
ASF.
 Map distribution of pig density as well as natural
hosts/vectors.
 Prevalence of the disease trough and appropriate
sampling strategy and the application of prescribed
ASF diagnostic tools.
 Molecular studies of virus from outbreaks and natural
hosts.
 Examine mechanisms of natural resistance in domestic
pigs.

53. MAIN CONCLUSIONS
Transfer technology at
regional laboratory level
FOLLOW UP

54. FUTURE ACTIVITIES
Key Areas of Research with implications for
control will mainly include:
Further investigation of the importance of the
warthog/tick sylvatic cycle in causing disease outbreaks
through genotyping of viruses from these species from
multiple sites within the region. Kenya and Uganda.
Focus on in-depth surveillance and outbreak
monitoring of ASFV in Tanzania
Link virulence phenotype of viruses determined
through experimental infection of indigenous and exotic
domestic pigs in Spain and Kenya with complete
genome sequences of three Kenyan isolates.

55. AKNOWLEDGMENTS
Tanzania Congo Rep
Cote d`Ivoire

56. AKNOWLEDGMENTS
EU Reference Laboratory CISA-INIA
INTERNATIONAL LIVESTOCK RESEARCH INSTITUTE
Special thanks to the coordinator at ILRI: Dr. Richard Bishop

57. Our Thanks/Ahsante Sana
TO OUR HOST
COUNTRY:
AND
SCIRO sponsor of this
Event

58. MY SPECIAL THANKS
Dr. Carmina Gallardo Frontaura