EEHV Workshop Lauren L. Howard, DVM, Dipl. ACZM San Diego Zoo Safari Park

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1 EEHV Workshop 2017 Lauren L. Howard, DVM, Dipl. ACZM San Diego Zoo Safari Park

2 Workshop Attendees 78 Participants 9 Countries 21 talks 2 practicals

3 Regional Summaries North America 35 cases in calves born since fatalities, 11 survivors, 68% fatality Transport questions Fleshing out EEHV Advisory Group

4 Regional Summaries Europe : 7 fatal cases, 2 survivors European EEHV Research Steering Group Veterinarians with no research affiliation as part of group Need to Research Funding to Save Elephants Research Priorities Vaccine Development Cell line culture Virus culture Immunology (humoral/cellular) Coagulation profile

5 Regional Summaries Asia >80 cases of EEHV in Asia 12 wild elephants in India Thailand 34 cases, 26 total in India Goals of Asia EEHV Working Group -evaluation of EEHV epidemiology and risk factors -establishment of cpcr and qpcr EEHV laboratories: PRIORITY -surveillance of wild elephants for EEHV Thailand November 2017: Train the Trainer PCR Workshop 3 rd EEHV in Asia Working Group Meeting

6 Regional Summaries Asia-Thailand Retrospective study cases EEHV with samples confirmed by PCR (2 calves died in last two weeks) 32 fatal cases 3 survived Most serious health problem affecting elephants in Thailand

7 PhD and Research Projects Underway Genetic Diversity of EEHV genes Compared EEHV gene sequences of 5 genes between fatalities and survivors to find clues to pathogenicity Identical genetic strains identified from fatalities that occurred within several years of each other Suggested reclassification of EEHV1B because very different from EEHV1A?

8 PhD and Research Projects Underway Exploring Interferon System of Elephants Interferons induce an antiviral state in cells There is much to be understood about interferon in elephants, to identify which IFN they are producing Interferons may have a therapeutic application to EEHV HD

9 PhD and Research Projects Underway Investigating the Host Response to EEHV Differences in host response to EEHV viremia may determine outcome Evaluation MHC and toll-like receptors Comprehensive pathology review Planning to evaluate immune, coagulation, and inflammation status during viremia Collecting cell culture attempts and putting together in a review paper

10 PhD and Research Projects Underway Genetic analysis of Coagulation Factor VII Factor VII mutation identified in a wild born Asian elephant in Australia (M Lynch et al) Unable to associate Factor VII mutation with EEHV HD cases Other small mutation points found in elephants, more investigation needed In human studies, vitamin K coagulation factors are less complete before 6 months of age

11 Potential New Applications Next Generation Sequencing Could help us better understand: Genetic diversity of viral populations Viral evolution on a more specific level, looking at different viral populations within individuals Transmission of viruses, and how viruses change within the host

12 Ongoing Research T cell Responses in Elephants T cells/ cell mediated immunity is important in EEHV immune response Development of T cell assays (EliSPOT assays) to screen different EEHV proteins as potential vaccine candidates MCP and Gb are conserved between EEHV1A and EEHV 1B Could T Cells be used for targeted treatment of EEHV? (Immunotherapy)

13 Ongoing Research Evolution of Molecular Genetics in EEHV Almost 20 years since Index case: Kumari at National Zoo EEHVs: single clade, arose in elephantids around 100 million years ago Gamma herpesviruses: around but don t cause disease OX2 (CD200) EEHV genes show high degree of strain divergence Important but unknown role in biology of AT rich branch of EEHV group

14 Clinical Research Surveillance of Berlin Zoo elephants Anchali, 4yo calf shedding EEHV for >1 year Lancet Technique for Blood collection for qpcr Whole blood still best: allows for quantification and CBC Bench top studies show no loss of specificity if use foam swabs or little toilet brushes (flocked swabs)

15 Clinical Reports GOAL: weekly qpcr of elephant calves 1-8 years of age Subclinical Viremia does occur Changes in hemogram associated with early viremia Decreased monocytes Decreased platelets Relative increase in heterophils Herd stress events associated with EEHV antibody changes?

16 Clinical Reports: SURVIVORS!!! Thailand 2.5 yo male elephant EEHV1A, first case managed in 2014 USA: EEHV5 in 2 yo male calf: Preparation/Communication EEHV1A in 4 yo female calf: new tweaks to current recommendations Canada: EEHV in a 2 yo female calf, managed w/ cpcr only Sweden: EEHV1B in 3 yo female calf, managed intensively, many sedations

17 Workshop Discussions Host Immune Response: the next microscopic frontier Asia: the next macroscopic frontier Cell Culture Attempts: document all techniques tried so far Investigate clustering of EEHV HD cases in some zoos? Breeding, no EEHV HD cases reported: Hamburg, Hanover, Emmen Breeding, EEHV HD cases/fatalities seen: Chester, Whipsnade Calf Access for blood collection Challenges perceived with protected contact Option for strategic grey area in handling restrictions <1 year of age?

18 Workshop Discussions: Calf Access Need for resources, awareness at Director Level Adequate facilities for training Adequate number of keepers Adequate funding for clinically based research travel and training for keepers and veterinarians Question for Group: HOW TO RAISE AWARENESS WITH DIRECTORS?

19 Next Steps? Share results of this workshop: how? Talk about your trip here when you get home Support each other, zoos with EEHV HD cases Share our future results, both successes and failures Address calf access issues