Hepatitis E virus control in the pig reservoir

Transcription

1 Hepatitis E virus control in the pig reservoir Wim H. M. van der Poel June 2018 Wageningen University

2 Wageningen Bioveterinary Research Wageningen BioVeterinary Research Lelystad Wageningen University campus Wageningen

3 Presentation outline Introduction Hepatitis E disease impact Swine reservoirs Foodborne transmission Direct exposure from swine HEV prevention and control Wageningen University

4 Hepatitis E virus Symptoms: fever, jaundice, hepatitis, hepatomegaly, anorexia, malaise, nausea, vomiting Overall case-fatality rate: 1%-4% Fam. Hepeviridae ssrna, three ORFs Non-enveloped virus, 7-34 nm Cell culture propagation difficult Wageningen University

5 Hepatitis E virus 2017 Increasing HEV incidences in Europe Increasing HEV RT-PCR detections in foods Liver sausage, paté HEV infection associated with neural disorders (Dalton et al., 2016) Guillain-Barré syndrome and neuralgic amyotrophy are associated with locally acquired HEV in approximately 5 and 10% of the cases Wageningen University

6 Hepatitis E in the Netherlands Prevalence and disease estimates >100 hospital treatments per year >20 serious acute clinical infections per year >300 cases in immunocompromised per year 1-3% of solid organs transplant patients develop chronic hepatitis E HEV seroprevalence >10% > infections per year

7 Hepatitis E virus infection notifications The Netherlands (cumulative) Wageningen University

8 Hepatitis E virus genotype 3 subtypes and phylotypes in humans and swine The Netherlands Hogema et al.,

9 Food and environmental routes of hepatitis E virus transmission Van der Poel, 2013 Wageningen University

10 Hepatitis E virus reservoirs and hosts

11 Hepatitis E virus taxonomy and predominant hosts Orthohepevirus A Genotype 1 and 2 human Genotype 3 human, swine, deer Genotype 4 human, swine, deer Genotype 5 and 6 wild boar Orthohepevirus B chicken Orthohepevirus C rat, ferret, mink Orthohepevirus D bats Piscihepevirus A cutthroat trout Smith et al., 2014

12 Hepatitis E virus seroprevalences domestic swine and wild boar Europe Country seroprevalence Reference Netherlands 73% (803/1100) Van der Poel et al., 2014 France 31% (2035 /6565) Rose et al., 2011 Germany 65% (216/332) Dremsek et al., 2013 United Kingdom 93% (584/629) Grierson et al., 2015 Belgium 73% (613/840) Thiry et al., 2014 Spain 20% (233/1141) Jimenez de Oya et al., 2011 Ireland 27% (89/330) O Connor et al., 2015 Switzerland 58% (1161/2001) Burri et al., 2014 Country seroprevalence Reference Netherlands 18% (29/164) Van der Poel 2016 (in prep.) France (Corse) 26% (62/284) Jori et al Germany (Saxony-A) 33% (109/330) Denzin et al., 2013 United Kingdom Not reported Belgium 34% (130/383) Thiry et al., 2015 Italy 1,6% (3/196) Di Profio et al., 2016 Spain 43% (63/150) De Deus et al., 2008 Slovenia 30.2% (87/288) Zele et al., 2016 Wageningen University

13 Genotype 3 Genotype 4 Wageningen University Geographical distribution zoonotic hepatitis E viruses in swine

14 HEV transmission in domestic pigs (Bouwknegt et al., 2008) Infectivity period 29.7 days; R0 = 10.7 ( ) Conclusions: HEV will cause large outbreaks Pigs are true reservoir of HEV Gt3 Inoculated Animal (IC) 2 nd contact animal (C2) 1st contact animal (C1) T 2 T 1 1-to-1 Experiment Box 1 40 spfpiglets HEV Gt3 isolate Fecal Box 2 samples serum samples 3rd contact animal (C3) Box 3

15 HEV antibody prevalence (Bouwknegt et al., 2008) 40% Non-inf Inf. Sp. Inf. Se Inf. SE en SP 35% Seroprevalence 30% 25% 20% 15% 10% 5% 0% Sw ine veterinarians Non-sw ine veterinarians General population More exposure, higher seroprevalence Difference between swine vets and GP Large credibility intervals

16 Other routes of Hepatitis E virus transmission Blood donation, Blood products Solid organ transplantation Intravenous drug use Pharmaceuticals of swine origin (i.e. heparin, pancreatin) Xenotransplantation (i.e. heart valves pancreas cells, liver cells) Crossan et al., 2013; Hewitt et al., 2014; Pas et al., 2012; Christensen et al., 2002; Denner 2015 Wageningen University

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18 HEV in byproducts and sausages Hemaglobin Spray dried porcine plasma (SDPP) Fibrinogen Blood/plasma RT-PCR detections 1-4 * 10E copies/gram Boxman et al., 2017 Said et al., 2017 Hulst et al., 2017 EFSA., 2017

19 Spray dried porcine plasma (SDPP) By-product of pork production. High quality proteins of porcine origin Used in food industry ( filler ) Common in starter diets of weaned piglets and in pet foods Has been associated with spread of porcine viruses Virus sequences detected in SPDD product Viable (infectious) virus may be present in SPDD Hulst et al., 2017 Wageningen University

20 Spray drying process porcine plasma Wageningen University

21 Experimental spray-drying (Büchie) Porcine serum substrates spiked with prototype viruses Testing of virus reductions (PCR and cell culture) Conclusion: High ph (>9.8) and preceding heat treatment indicated to inactivate viruses. Hulst et al., 2017 Wageningen University

22 Hepatis E virus in pork sold in the UK I call it the Brexit virus. It attacks the liver and nerves, with a peak in May Dr Harry Dalton Sunday Express, May 2017 Daily Express, May

23 Import and export of pork in The United Kingdom

24 Imported pork for consumption Sources: BPEX and ADHBpork (UK), CBS (NL), SEGES (DK), Agreste Conjuncture (Fr), VLAM (Be), Comtrade, Central Statistics Office, FAMMU/FAPA and MRIRW/ZSRIR (Pl), BLE and BMEL (De). 24

25 Countries where pork is imported from Table 2. Countries where fresh or frozen pork for consumption is imported from Pork consumption Country Main countries where pork is imported from Belgium 1) Netherlands, 2) Germany, 3) France Denmark 1) Germany, 2) Poland, 3) Netherlands France 1) Spain, 2) Germany, 3) Belgium Germany 1) Netherlands, 2) Belgium, 3) Denmark United Kingdom 1) Denmark, 2) Netherlands, 3) Germany Netherlands 1) Germany, 2) Belgium, 3) United Kingdom Poland 1) Belgium, 2) Germany, 3) Denmark Sources: BPEX (UK), CBS(NL), COMTRADE (Pl), AHDBpork (UK), Danish Agriculture and Food Council (DK), Agreste Conjuncture (Fr), vlam (Be), Central Statistics Office (Po) FAMMU/FAPA, based on data from MRIRW/ZSRIR (Po) 25

26 Hepatitis E virus characterizations in swine Obtained number of ORF2 sequences 2016 Table1. Numbers of Hepatitis E virus ORF2 sequences from swine and human samples collected in 2016 as provided by the participating countries Country Porcine ORF2 sequences Human ORF2 sequences Total ORF2 sequences Belgium Denmark France Germany United Kingdom Netherlands Poland Total

27 HEV phylogeny human and swine sequences 27

28 Screening high health swine farms Netherlands 2015 Herd (3-6 months old fattening pigs) Ab-pos (Elisa Van der Poel et al., 2014) A 10/10 100% B 11/11 100% C 9/10 90% D 8/12 67% Prevalence Estimate E 12/12 100%

29 HEV detections (RT-PCR) in swine farms Location Type of sample HEV positives Inside farm building Feces, surface swabs 5/149 (3%) Outside farm building Trucks Slaughterhouse yard Silo surroundings; trucks routes; feces on outside dock Mudguard; carpet; trailer Trucks routes; utility vehicle 11/101 (11%) 4/98 (4%) 12/104 (12%) Nantel-Fortier et al., 2015 Wageningen University

30 Hepatitis E virus inactivation Stable in water environment; also in blood No complete inactivation between 45 and 70C (Emerson et al., 2005) Inactivation: Chlorine (Girones et al 2014) Heating >71 C ( Barnaud et al., 2012); >70 C, 5 min (Imagawa etal 2018) UV (Cook and VanderPoel 2015) Studies hampered by the fact that there is not an easy HEV cell culture propagation method available and no appropriate surrogate Wageningen University

31 Hepatitis E Vaccine Recombinant hepatitis E vaccine, HEV 239 Purified amino acids of capsid protein (HEV gt1 ORF2) expressed in E. coli. Xiamen Innovax Biotech, Xiamen China. Heterologous protection against gt3 and gt4 unsure Wageningen University

32 HEV prevalence profiles (assuming global transmission) Backer et al., 2012 maesured estimated Pigs 0-25 weeks of age Plots of 10 herds Wageningen University

33 Effect of vaccination Backer et al., 2012 Animals vaccinated before entering herd Fraction of infectious animals at slaughter age If reduction below 75%, better to delay vaccination Wageningen University

34 Global One Health Global one health is the combined effort of multiple disciplines to improve health of humans, animals and plants within sustainable ecosystems by using an integrated systems approach to come to transnational solutions. Global One Health a new integrated approach by Fresco L.O. et al. 2015, published by the Trilateral Commission. 34

35 Increasing public health risk of HEV in the developed world Aging population Increasing number of blood transfusions and organ transplants increasing number of immunocompromised individuals /receiving immunosuppressive treatment Increasing consumption of pork and related products More virulent HEV strains

36 Conclusions Increasing impact of HEV infections Swine are the main reservoir of zoonotic HEVs worldwide Foodborne infection likely to be the main transmission route Very stable HEV reservoir in swine, vaccination will be needed to reduce HEV in swine HEV control needed at multiple points along the food chain One-Health approach needed to combat hepatitis E Wageningen University

37 Acknowledgements Renate Hakze (WBVR) Jantien Backer (WBVR) Nicole Pavio (ANSES) Ana Maria de Roda Husman Saskia Rutjes (RIVM) Martijn Bouwknegt (RIVM) Mart de Jong (WUR) Nigel Cook (FERA) Hans Zaaijer (Sanquin) Boris Hogema (Sanquin) Rosina Girones (UB) Lars Larsen (DTU-VET) Jesper Skag Krog (DTU-VET) Ilaria di Bartolo (ISS) Malcolm Banks (APHA) Alessandra Berto (WBVR) Els van Coillie (ILVO) Edmilson Oliviera de Filho (UdL) Frank Harders (WBVR) Vanessa Suin (WIV-ISP) Artur Rzezutka (LVRI) Bhudipa Choudhury (APHA)

38 Thank you Wageningen University