African Swine fever – a real and present global threat Should the Caribbean countries be worried? CaribVET Webinar, 27 th Sept 2018 Chris Oura Professor of Veterinary Virology School of Veterinary Medicine Faculty of Medical Sciences The University of the West Indies Trinidad and Tobago chris.oura@sta.uwi.edu University of the West Indies
Today’s Presentation • The virus and the disease • Current global situation • Why are we struggling to control it? • Prospects for a vaccine? • Future risks for the Caribbean • What next?
First of all – why the fuss? Main global exporters of pork - 2017: 1.Germany: US$4.8 billion (15.8% of total exported pork) 2.United States: $4.6 billion (15.2%) 3.Spain: $4.1 billion (13.5%) 4.Denmark: $2.7 billion (9.1%) 5.Canada: $2.5 billion (8.4%) 6.Netherlands: $2.2 billion (7.2%) 7.Brazil: $1.5 billion (4.9%) 8.Belgium: $1.4 billion (4.8%) 9.Poland: $1.1 billion (3.5%) 10.France: $932.9 million (3.1%) 11.Mexico: $527.6 million (1.7%) China produces over 12.Ireland: $502.6 million (1.7%) half of the worlds pork 13.Austria: $433.5 million (1.4%) 14.Hong Kong: $427.2 million (1.4%) 15.Chile: $396.5 million (1.3%)
Introducing the virus • Large! • Complicated! ……….and very tough! KP177R MGF100-1R X69R MGF505-1R MGF110-13L 31.6 MGF360-1L L83L MGF110-1L MGF110-4L MGF110-8L MGF110-14L MGF360-4L MGF360-6L MGF300-1L MGF300-4L MGF360-9L MGF360-11L MGF360-12L MGF360-2L MGF360-3L MGF110-2L MGF110-5L-6L MGF110-9L MGF110-12L MGF360-8L MGF360-10L MGF360-13L L60L MGF110-3L MGF110-7L MGF110-11L A151R MGF505-3R MGF505-5R A118R MGF505-2R MGF505-4R MGF505-6R MGF505-7R MGF505-8R MGF505-10R A104R MGF360-15R A137R F778R F165R 63.2 MGF360-14L A224L A240L A238L A859L A179L F317L F334L F1055L K196R EP424R EP153R C122R K205R K421R EP84R EP152R EP402R EP364R M448RC129R C717R C315R C962R 94.8 K78R K145R EP1242L M1249L C84L C257L C147L B962L C475L C62L B385R B125R B263R G1211R CP503R B318L B169L 126.4 B475L B354L B602L B646L B117L B175L B66L G1340L CP123L CP2475L CP204L B119L B438L B407L H124R H223R CP312R O61R NP868R D250R D205R S273R P1192R H171R H339R H240R 158.0 CP80R H108R O174L NP1450L NP419L D129L D339L D1133L D117L D345L H359L R298L D79L S183L Q706L DP63R DP96R QP383R E423R E301R E165R E120R E111R I226R I73R MGF360-16R L9R MGF360-18R MGF360-21R I177L 189.3 QP509L E184L E146L E66L I243L I329L I215L DP238L MGF505-11L L7L L11L DP71L E183L E199L MGF100-1L L8L L10L I267L I196L
I African Swine Fever virus Lis /57 68 XXVII Zim 1/92 lots of different (geno)types MOZ 1/03 MOZ 2/02 64 MOZ 1/05 II Georgia /2007 67 Mad 1/98 Lus1/93 MOZ 1/02 Bot 1/99 III XIX RSA 2/96 XX RSA 1/95 RSA 1/99 IV 98 VII RSA 1/98 57 Spec 245 XXII Ten /60 V 88 VI Moz 1/94 RSA 1/96 XXI XVIII Nam 1/95 Uga 1/95 IX 100 Uga 3/95 Moz 1/01 VIII Kab /62 XI 50 MFUE 6/1 XII 76 XIII 57 Sum 14/11 TAN 1/01 XV XVI TAN 1/03 72 XIV NYA 1/2 0.005
The disease – African Swine Fever
Recognising African swine fever Clinical signs: Loss of appetite, recumbancy (won’t get up), fever, vomiting, diarrhoea (bloody), joint swelling, skin haemorrhages Postmortem signs: Haemorrhages in many organs including lymph nodes and under the skin eg ears Enlarged, haemorrhagic, friable spleen
Haemorrhagic Lymph nodes and Kidney
Enlarged friable dark Spleen
Haemorrhages in heart
Haemorrhagic lesions in gut
Chronically infected pig
2011-2017 2017
African swine fever - August 2018 140,000 pigs on one farm slaughtered in Romania
Situation in China now – Sept 2018 6 th Sept 2018 Introduced into China in March / April??? OIE – 26 th Sept 2018 OIE – 26 th Sept 2018
The amount of live pigs sold by these six provinces reached 174,175,000, occupying 25.3 percent of the nationally sold live pigs in 2017.
And then earlier this month…… At least 9 wild boar found to be infected so far …………
How is the virus being transmitted? In Africa Ticks not confined to Africa
How is the virus being transmitted? Transmission associated with blood
Key Risk factors – why is control proving so challenging? Wild / domestic pigs eat anything! Contact between Wild Boar Virus entering the Catering cycle and backyard / feral pigs Cured, smoked, raw hams Lack of Biosecurity Movement of humans / migrant workers with pork products Human behavior – poor practices • Lack of knowledge / information • Money constraints • Lack of compensation Surviving swine Ticks? becoming carriers? Long distance movement of wild boar – hunting?
Key Risk factors – why is control proving so challenging? 1. Role of Wild Boar – is ASFV now endemic in wild boar? Contact between wild and domestic pigs Modelled wild boar population density in Europe (source: FAO/ASFORCE, May 2015)
Key Risk factors – why is control proving so challenging? 2. Role of low biosecurity (backyard and feral pigs) No movement controls in low biosecurity sectors Densities of domestic pigs in the low biosecurity sector in Europe. Data: various statistical data 2008- 2011, FAO/EMPRES.
Key Risk factors – why is control proving so challenging? 3. Role for recovered ‘carrier’ pigs (domestic and wild)? • Different forms of the virus are circulating: high – low virulence • Carrier status in recovered pigs / wild boar
Key Risk factors – why is control proving so challenging? 4. Role of humans Farmers / hunters - Lack of Low levels of compensation information • Disposal of dead pigs – rivers • Selling pigs in the face of an outbreak • Movement of sick pigs to market • Swill feeding • Vehicle contamination • Vets, farm workers and hunters • Poor levels of biosecurity • Carcase disposal - flies Source: Empress Watch, 2013.
Key Risk factors – why is control proving so challenging? 5. Role of ticks – are they present and contributing ? Ornithodorus tick distributions
African swine fever – main challenges we face Very resistant virus Complex – multiple genotypes Present in domestic and wild swine Signs and symptoms confused with other diseases Reservoirs of infection (vectors / wildlife) Carrier animals present? Lack of effective vaccines Rapid uncontrolled spread in developing countries
Why NO vaccine for ASFV? • Large complex virus with many proteins (60-185 encoded) • Inactivated / passaged virus does not protect • Vaccine candidate antigens (viral proteins) do not protect • Vaccine trials require high containment facilities - expensive • Largely African problem (in past) - lack of commercial market. • Few groups involved in research – USA example
The six million dollar question: Should you worry about African Swine Fever in the Caribbean? • Spreading around the world (EU / Russia / China /Africa) • High levels of mortality in pigs (domestic and wild) • Evidence that the virus may be attenuating in the field • Very tough and resistant virus – in processed meat • Many people coming from infected regions of the world (sandwich effect) • Vaccine still not in sight
Risk factors to assess - Caribbean • Backyard / outdoor / wild pigs - biosecurity • Ornithodorus ticks – contact with pigs • Levels of biosecurity on domestic pig farms • Border security – illegal / legal imports of pig products (and possibly feed) from abroad • Rapid accurate laboratory diagnosis essential Virus is only a short flight / boat ride away!
Advise to pig farmers in the Caribbean Biosecurity, Biosecurity, Biosecurity • Review and increase existing levels of Biosecurity on the farm • Ensure pigs are not fed catering waste, kitchen scraps or pork products, • Do not allow pig-meat products onto farms, eg in workers’ lunches. • Ensure that visitors have not had recent contact with affected regions. • Anybody returning from an affected country should avoid contact with domestic pigs, whether commercial holdings or smallholdings, until they are confident they have no contaminated clothing, footwear or equipment. • Familiarise yourself with the clinical signs of ASF and report any suspicious illnesses immediately.
Thanks very much! Any Questions? University of the West Indies EU Reference Laboratory for ASFV, Madrid, Spain Carmina, Marisa and Jose Manuel
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