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ASF IN EUROPE: MAIN CHALLENGES
Prof. José M. Sánchez- Vizcaí[email protected]
OIE-ASF Reference Laboratory
www.sanidadanimal.info
ASFV: A old friend 1978-
MAIN WORK:
DIAGNOSIS TEST &
REAGENTS
EPIDEMIOLOGY-CONTROL
and ERADICATIONOIE ASF REFERENCE LABORATORY
200 nmMore than 100 structural
proteins
Very complex virus, big syze, large genome: 170 kb
Replication in macrophages
NO production of neutralizing antibodies
ASF. The most complex disease of swine
Very complex molecular structure
Genetic variability
22 genotypes (VP72)ONLY TYPE II&I
VACCINE FOR ASF
Many trials have been done in the last decades looking for an effective
vaccine against ASFV:
1.INACTIVATED VACCINES Ab response NO PROTECTION
2.ATTENUATED VACCINES Ab + cytotoxic specific CD8
PROTECTION against homologous & heterologous strains BUT
SAFETY PROBLEMS, No long term studies
ASF VACCINE: Spain1965
A VACCINE FOR ASF
3. SUBUNIT VACCINES very poor, PARTIAL PROTECTION but
SAFE ALTERNATIVE
4. DNA VACCINES PARTIAL PROTECTION with some candidates
Different expression vectors (plasmids, Bacman…)
Enhance CD8 response with no Ab protection
ANTIBODIES and CITOTOXIC CD8 (T cells)ARE RELATED WITH PROTECTION
Ab CHRONIC FORMS IN ENDEMIC AREAS
Eradication without vaccine is
possible but not easy…
MORE RESEARCH IS NEEDED
Ab
PIGS (D & W)
and SOFT
TICKS
To keep in mind
VIRUS
Infection Clinical Signs/Dead Could be Carriers (10%)
•Viremia: starts 2-3 days to 8 days postinfection, and persists for a long time (months)•Specific Antibodies: from day 7-11 during months, even years (all live)•Virus excretion: from the early infection (day2) for long time. Even after recover
AGENDA :
• ASF Epidemiological update. Europe
• Potential ASF spread
• Risk assessment and surveillance program
• Conclusions
The viruses from Poland and Lithuania had a TRS insertion identical to
that present in ASFV isolates from Belarus and Ukraine. This TRS
insertion was absent in the remaining viruses from eastern Europe,including Tver Oblast (Russia, 2012) and Georgia, 2007.
Gallardo et al., Genetic variation among African swine fever genotype II viruses, eastern and central Europe. Emerg Infect Dis. 2014- Sep;20(9):1544-7. doi: 10.3201/eid2009.140554.
Highly virulent isolate
ONLY ACUTE FORMS OF THE DISEASE HAVE BEEN OBSERVED IN THE AREA
Fever, short incubation period, high mortality (Gabriel et al., 2011; Blome et al., 2012; Sánchez-Vizcaíno et al., 2014)
1. The Infection
SYMPTOMS and LESIONS
Only Fever and Dead
In Africa 22 genotypes / Hyper-acute-acute-sub-acute forms
In East Europe genotype II /only acute isolates are circulanting
DIFFERENT CLINICAL FORMS
Clinical Signs: Easily Confused with:
Classical Swine Fever
Erisipelas
Salmonellosis
Other Septicaemic conditions
PDNS
• To Keep in mind:
. To be aware and ready is the key
• ASF Clinical Information to veterinarian and farmers is very important for an early detection. In general no clear and good information about ASF is provided. The entrace of the disease is not explosive in most cases.
• Laboratory diagnosis and differential diagnosis is critical.
• EPI and LAB together the best solution.
WHY?. ASF ENTRANCE IN
CAUCASUS REGION
• Combination of factors:
• Increase of ASF in Africa
• Economic crisis
• Swill feeding
• BY. Lack of biosecurity
PIG PRODUCTION:
Armenia & Georgia.
• Traditional and seasonal production
• 85-97% pigs in back-yard system (1-2 pigs/farm)
• Swill feeding, free roaming pigs, no BS
1. Transcaucasian countries
INTRODUCTION: waste from international ships swill feedingTRANSMISSION: • Legal & illegal mov of pigs and products• Free roaming pigs• Wild boar Sources: FAO 2008, 2013; EFSA 2010,2014
ABSENCE OF INFORMATION
2. Russian Federation
ASF NOTIFICATIONS in RF:
• 63% BY
• 18% SMALL
• 16% HBS UNITS
• SLAUTHERHOUSES,
PROCESSING PLANTS,
2014
Sanchez-Vizcaino et al., 2012; OIE 2014
Role of wild boars and domestic pigs in the spread of African swine
fever in Russian Federation (2007-2013)
De la Torre, et al., 2014
3. Ukraine & Belarus
PIG PRODUCTION
• Belarus: 43% HBS
• Ukraine:80%HBS
BACK-YARD in Western regions
INTRODUCTION: • UKRAINE 2012: swill feeding• BELARUS: contaminated feed
(RF)• Wild boar
EFSA, 2014
Back-yard pig density (FAO, 2010)No border with RF
4. EU
PIG PRODUCTIONIMPORTANT DIFFERENCES BETWEEN EU AFFECTED
COUNTRIES
Sources: Glipha & FAOSTAT (FAO)
4. EU
INTRODUCTION 1st cases Lithuania & Poland (January 14): WILD BOAR
(genetically identical to Ukrainan and Belarusian isolates and some from the Russian Federation.
All the studies performed so far in Europe (Spain and
Sardinia) revealed that the wild boar by its own it is no able to
mantain the disease without the re-infection from
domestic/contaminated products (Laddomada et al., 1994; Manelli et
al., 1997, 1998; Mur et al., 2012; Rolesu et al., 2007).
THE ROLE OF THE WILD BOAR
4. EU
Latvia: •WILD BOAR from Belarus•Domestic pigs swill feeding in Back-yard
First domestic outbreak
High ASFV pressure(wild boar andcontaminatedmeat) from Belarusin May/June(Cvet, 2014)
4. EU
Latvia: • Domestic pigs Low BS back-yard farms. Several introductions
at the same time
• Wild boarmovement/ slaughterhouse disposal?
High ASFV pressure (wildboar and contaminatedmeat) from Belarus inMay/June
(Cvet, 2014)
4. EU
Lithuania: • Domestic pigsHBS FARM
• HUMAN FACTOR is the most likely source of introduction. No explosive ASF presentation
• Potential spread
Good BS and preventivemeasure in place
4. EU
Data Source: OIE WAHID, own ellaboration
ASF epidemic curve in European Union (2014)
Similar to European East Countries
LEVELS OF RISK
•Part III: pig holdings and feral pig population
•Part II: only feral pig pop.
•Part I: risk due to proximity to feral pig pop.
Prohibitions:
•Dispatch to other MS and third countries (all parts)
•Dispatch of live pigs (II & III)
•Dispatch of semen, ova, embryos/meat/products (III)
•Especial derogations available
(2014/178/EU)
UE Current situationUpdated 5th Sept. SANCO, 2014
Main Challenges
. Stop the potential endemicity of ASF in wild boar
. Avoid pigs farms in suitability wild boar áreas
. Increase biosecurity in back yard production
. Used new non invasive methodology for the evaluation of
Asf virus and antibodies in wild boar (Ej. Oral fluid,faeces..)
The best recipe for ASF
Awarness and Early Detection
Early detection: Risk Assessment and Surveillance
Program
Control actions: A good Contingency plan
Control Actions
EVALUATING THE RISK OF ASFV
ENTRANCE IN CHINA
Pig census 679 million
(estimated)
Pig product imports!
(56% global trade)
EVALUATING THE RISK OF ASFV
ENTRANCE IN CHINA
2500km aprox.
Increasing commercial and cooperation
relations with African continent
840 million of kg of pig offalsimported in China in 2012
Only East Europe
Specially in Nigeria and South Africa(more than 50.000 residents)
Very strong connections by boat with Africa(new ports under construction)
AFRICA and East Europe
Mur, et al. 2014
840 million of kg of pig offalsimported in China in 2012
From Russian Federation
Specially in Nigeria and South Africa(more than 50.000 residents)
EVALUATING THE RISK OF ASFV EXPOSURE IN
CHINA
Evolution of pig production systems in China (Source:
Schneider y Sharma, 2014)
Even the specialized production not allways good biosecurity level(Quaratine, separation between production units…) McOrist et al., 2011
Presence of otherdiseases:
PRRS, CSF, FMD
Confussionand
late diagnosis
Exposure
Routes of introduction
Spread
Infection at origin
OUTSIDE CHINA
IN CHINA
Risk assessment workshop
Russia Africa
Hazard Identification
At each entry point in China….
…for now in two regions with potentially different routes of entry: Xinjiang and Shandong
Hazard Identification: Routes of introduction
TRADE
Animal products
Semen and ova
Meat and meat products
Live animals
Domestic pigs
Wild pigs and boars (zoos, hunting, etc)
FOMITES
Leftovers, people, vehicles, other fomites
WILD BOAR
LEGAL orILLEGAL
Imported live pigs: Please identify the Russian regions from where live pigs are imported with destination Xinjiang
Russian Regions of origin of live pigs
LEGAL orILLEGAL
1
76
3 4 5
2
8
Xinjiang
1 (negligible)
2 (low)
3(médium)
4(high)
5 (very high)
Plane
Road
Train
Imported live pigs. Please identify the Russian regions from where live pigs are imported, with destination
ShandongRussian Regions of origin of
live pigs1
76
3 4 5
2
8
Shandon
g1 (negligible)
2 (low)
3(médium)
4(high)
5 (very high)
Plane
Road
Train
Boat
A WORLD FREE of [email protected]