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Knüppel S, Balfanz F, Riedel C, Strauss V, Hoornweg TE, Dimmel K, Walk K, Kübber-Heiss A, Posautz A, Voracek T, Abdelgawad A, Trimpert J, Hering-Hagenbeck S, Rümenapf T, Auer A. Severe Elephant Endotheliotropic Herpesvirus 6 Associated Disease in Two African Elephants Under Human Care in Austria. Animals (Basel) 2025; 15:1482. [PMID: 40427359 PMCID: PMC12108372 DOI: 10.3390/ani15101482] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2025] [Revised: 05/12/2025] [Accepted: 05/14/2025] [Indexed: 05/29/2025] Open
Abstract
In 2021, a captive two-year-old African elephant died of cardiovascular failure in Austria. Lesions were indicative of elephant endotheliotropic herpesvirus (EEHV) associated disease, and the presence of EEHV6 could be detected by PCR. About two months later, an eight-year-old female elephant from the same herd showed typical clinical signs of EEHV-related hemorrhagic disease, which coincided with EEHV6 viremia. The animal underwent anti-herpesviral therapy and recovered quickly. Subsequently, blood and trunk wash samples from all elephants of the herd were monitored weekly for the presence of EEHV6-specific nucleic acids by qPCR. A retrospective analysis of the samples revealed repeated EEHV6 reactivation and the presence of EEHV3 in the samples of one animal. Our findings underline the threat EEHV6 poses to juvenile African elephants and emphasize the need for regular monitoring of viremia and virus excretion to prevent fatalities and predict transmission events.
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Affiliation(s)
- Stella Knüppel
- Department of Biological Sciences and Pathobiology, Infectiology and Virology, University of Veterinary Medicine, Veterinärplatz 1, 1210 Vienna, Austria; (S.K.); (C.R.); (K.D.); (K.W.); (T.R.)
| | - Folko Balfanz
- Tiergarten Schönbrunn, Maxingstraße 13 b, 1130 Vienna, Austria; (F.B.)
| | - Christiane Riedel
- Department of Biological Sciences and Pathobiology, Infectiology and Virology, University of Veterinary Medicine, Veterinärplatz 1, 1210 Vienna, Austria; (S.K.); (C.R.); (K.D.); (K.W.); (T.R.)
| | - Verena Strauss
- Department of Interdisciplinary Life Sciences, Research Institute of Wildlife Ecology, University of Veterinary Medicine, Savoyenstraße 1, 1160 Vienna, Austria; (V.S.); (A.K.-H.)
| | - Tabitha E. Hoornweg
- Department of Biomolecular Health Sciences, Division of Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 1, 3584 CL Utrecht, The Netherlands
| | - Katharina Dimmel
- Department of Biological Sciences and Pathobiology, Infectiology and Virology, University of Veterinary Medicine, Veterinärplatz 1, 1210 Vienna, Austria; (S.K.); (C.R.); (K.D.); (K.W.); (T.R.)
| | - Karin Walk
- Department of Biological Sciences and Pathobiology, Infectiology and Virology, University of Veterinary Medicine, Veterinärplatz 1, 1210 Vienna, Austria; (S.K.); (C.R.); (K.D.); (K.W.); (T.R.)
| | - Anna Kübber-Heiss
- Department of Interdisciplinary Life Sciences, Research Institute of Wildlife Ecology, University of Veterinary Medicine, Savoyenstraße 1, 1160 Vienna, Austria; (V.S.); (A.K.-H.)
| | - Annika Posautz
- Department of Interdisciplinary Life Sciences, Research Institute of Wildlife Ecology, University of Veterinary Medicine, Savoyenstraße 1, 1160 Vienna, Austria; (V.S.); (A.K.-H.)
| | - Thomas Voracek
- Tierärztliche Ordination Tiergarten Schönbrunn, Seckendorff-Gudent-Weg 6, 1130 Vienna, Austria;
| | - Azza Abdelgawad
- Center for Infection Medicine, Institute of Virology, School of Veterinary Medicine, Freie Univerität Berlin, Kaiserswerther Str. 16-18, 14195 Berlin, Germany; (A.A.); (J.T.)
| | - Jakob Trimpert
- Center for Infection Medicine, Institute of Virology, School of Veterinary Medicine, Freie Univerität Berlin, Kaiserswerther Str. 16-18, 14195 Berlin, Germany; (A.A.); (J.T.)
| | | | - Till Rümenapf
- Department of Biological Sciences and Pathobiology, Infectiology and Virology, University of Veterinary Medicine, Veterinärplatz 1, 1210 Vienna, Austria; (S.K.); (C.R.); (K.D.); (K.W.); (T.R.)
| | - Angelika Auer
- Department of Biological Sciences and Pathobiology, Infectiology and Virology, University of Veterinary Medicine, Veterinärplatz 1, 1210 Vienna, Austria; (S.K.); (C.R.); (K.D.); (K.W.); (T.R.)
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Spencer Clinton JL, Hoornweg TE, Tan J, Peng R, Schaftenaar W, Rutten VPMG, de Haan CAM, Ling PD. The EEHV1A gH/gL complex elicits humoral and cell-mediated immune responses in mice. Vaccine 2024; 42:126227. [PMID: 39180978 DOI: 10.1016/j.vaccine.2024.126227] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2024] [Revised: 08/11/2024] [Accepted: 08/12/2024] [Indexed: 08/27/2024]
Abstract
Elephant endotheliotropic herpesvirus (EEHV) causes lethal hemorrhagic disease (HD) in Asian and African elephants. Although rapid detection of viremia and supportive treatments may improve survival rates, an effective vaccine would mitigate the devastating effects of this virus. In elephants, chronic infection with EEHV leads to adaptive immunity against glycoproteins gB and gH/gL, the core entry machinery for most herpesviruses. We previously evaluated two EEHV gB vaccines in mice but not a gH/gL vaccine. Here, we found that inoculation of mice with an adjuvanted EEHV gH/gL subunit vaccine induced a significant antibody response that was similar to the response observed in elephants chronically infected with EEHV. Moreover, the gH/gL heterodimer elicited polyfunctional T cells with a Th1 phenotype but no detectable Th2 response. These results suggest that gH/gL, possibly in combination with gB, may be suitable immunogens for a vaccine comprising herpesvirus glycoproteins that are known to mediate cell entry and infection.
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Affiliation(s)
- Jennifer L Spencer Clinton
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, 1 Baylor Plaza, MS: BCM-385, Houston, TX 77030, USA.
| | - Tabitha E Hoornweg
- Department of Biomolecular Health Sciences, Div of Infectious Diseases and Immunology, Fac of Veterinary Medicine, Utrecht University, Yalelaan 1, 3584, CL, Utrecht, Netherlands.
| | - Jie Tan
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, 1 Baylor Plaza, MS: BCM-385, Houston, TX 77030, USA.
| | - Rongsheng Peng
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, 1 Baylor Plaza, MS: BCM-385, Houston, TX 77030, USA.
| | - Willem Schaftenaar
- Veterinary Advisor EAZA Elephant TAG, Rotterdam Zoo, Blijdorplaan 8, 3041, JG, Rotterdam, Netherlands.
| | - Victor P M G Rutten
- Department of Biomolecular Health Sciences, Div of Infectious Diseases and Immunology, Fac of Veterinary Medicine, Utrecht University, Yalelaan 1, 3584, CL, Utrecht, Netherlands; Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Onderstepoort, Pretoria, South Africa.
| | - Cornelis A M de Haan
- Department of Biomolecular Health Sciences, Div of Infectious Diseases and Immunology, Fac of Veterinary Medicine, Utrecht University, Yalelaan 1, 3584, CL, Utrecht, Netherlands.
| | - Paul D Ling
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, 1 Baylor Plaza, MS: BCM-385, Houston, TX 77030, USA.
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Abdelgawad A, Nascimento M, Prahl A, Flügger M, Szentiks CA, Holtze S, Hildebrandt TB, Trimpert J. Fatal infection caused by a genetically distinct elephant endotheliotropic herpesvirus type 5 in a captive Asian elephant in Germany. Virol J 2024; 21:221. [PMID: 39285293 PMCID: PMC11406788 DOI: 10.1186/s12985-024-02477-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2024] [Accepted: 08/20/2024] [Indexed: 09/19/2024] Open
Abstract
BACKGROUND Elephant endotheliotropic herpesvirus (EEHV) infection is the most common cause for lethal hemorrhagic disease in captive juvenile Asian elephants (Elephas maximus). Although EEHV1 is known as the most likely cause of fatal haemorrhagic disease in Asian elephants, EEHV5 was lately involved in lethal cases of haemorrhagic disease in captive elephants. CASE PRESENTATION Here we report the first death of a four-year old Asian elephant diagnosed with EEHV5 in Germany. Molecular diagnosis yielded detection of EEHV5 DNA in all tested tissues. Histopathological examination revealed typical features of hemorrhagic disease in all examined organs. EEHV5 was sequenced from total DNA isolated from heart tissue by Illumina and Nanopore sequencing. Sequencing data showed 3,881 variants, distributed across the entire genome, compared to the published EEHV5 sequence. CONCLUSIONS We have detected EEHV5 in a fatal disease case of a male Asian elephant. Whole genome sequencing revealed substantial differences of our DNA isolate compared to available EEHV5 sequences. This report of fatal haemorrhagic disease associated with EEHV5 infection should raise awareness for EEHV5 as an important elephant pathogen. Genome sequencing and downstream SNPs analysis will further encourage future research to understand genetic diversity, pathogenesis and virulence of EEHVs with respect to developing new diagnostic methods, prophylactic strategies, and implementation of surveillance and control measures.
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Affiliation(s)
- Azza Abdelgawad
- Institut für Virologie, Freie Universität Berlin, Robert-von-Ostertag-Str. 7-13, 14163, Berlin, Germany
| | - Mariana Nascimento
- Institut für Virologie, Freie Universität Berlin, Robert-von-Ostertag-Str. 7-13, 14163, Berlin, Germany
| | - Adriane Prahl
- Tierpark Hagenbeck Gem. GmbH, Lokstedter Grenzstraße 2, 22527, Hamburg, Germany
| | - Michael Flügger
- Tierpark Hagenbeck Gem. GmbH, Lokstedter Grenzstraße 2, 22527, Hamburg, Germany
| | - Claudia A Szentiks
- Leibniz-Institute for Zoo and Wildlife Research, Alfred-Kowalke-Strasse 17, 10315, Berlin, Germany
| | - Susanne Holtze
- Leibniz-Institute for Zoo and Wildlife Research, Alfred-Kowalke-Strasse 17, 10315, Berlin, Germany
| | - Thomas B Hildebrandt
- Leibniz-Institute for Zoo and Wildlife Research, Alfred-Kowalke-Strasse 17, 10315, Berlin, Germany
| | - Jakob Trimpert
- Institut für Virologie, Freie Universität Berlin, Robert-von-Ostertag-Str. 7-13, 14163, Berlin, Germany.
- Department of Diagnostic Medicine and Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, KS, USA.
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Boonprasert K, Srivorakul S, Monchaivanakit N, Langkaphin W, Sripiboon S, Janyamethakul T, Srisa-ad C, Guntawang T, Brown JL, Thitaram C, Pringproa K. Characterizations of Elephant Endotheliotropic Herpesvirus Type 1A and 4 Co-Infections in Asian Elephant ( Elephas maximus) Calves. Vet Sci 2024; 11:147. [PMID: 38668415 PMCID: PMC11055005 DOI: 10.3390/vetsci11040147] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2024] [Revised: 03/16/2024] [Accepted: 03/18/2024] [Indexed: 04/29/2024] Open
Abstract
Three cases of double infection with elephant endotheliotropic herpesvirus (EEHV) types 1A and 4 in captive Asian elephants are presented. The first calf was a 4-year-old female that showed initial signs of lethargy and depression. The second calf was a 6-year-old female that displayed signs of depression and diarrhea and died within 48 h of the start of supportive treatment. The third was a 2-year-old male that died suddenly while living with the herd. Necropsies were performed in the first and second elephants, while only a tongue sample was collected from the third calf. EEHV infection was confirmed via quantitative PCR (qPCR) and gene sequencing, revealing double subtypes of EEHV1A and -4 infections. This study describes the hematological and pathological characteristics within the host following double EEHV infection.
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Affiliation(s)
- Khajohnpat Boonprasert
- Elephant Hospital, National Elephant Institute, Forest Industry Organization, Lampang 52190, Thailand
- Center of Elephant and Wildlife Health, Chiang Mai University, Chiang Mai 50100, Thailand
| | - Saralee Srivorakul
- Center of Veterinary Diagnostic and Technology Transfer, Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai 50100, Thailand
| | - Natcha Monchaivanakit
- Elephant Hospital, National Elephant Institute, Forest Industry Organization, Lampang 52190, Thailand
| | - Warangkhana Langkaphin
- Elephant Hospital, National Elephant Institute, Forest Industry Organization, Lampang 52190, Thailand
| | - Supaphen Sripiboon
- Department of Large Animal and Wildlife Clinical Sciences, Faculty of Veterinary Medicine, Kasetsart University, Kamphaeng Saen Campus, Nakornpathom 73140, Thailand
| | | | | | - Thunyamas Guntawang
- Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai 50100, Thailand
| | - Janine L. Brown
- Center for Species Survival, Smithsonian National Zoo and Conservation Biology Institute, 1500 Remount Rd., Front Royal, VA 22630, USA
| | - Chatchote Thitaram
- Center of Elephant and Wildlife Health, Chiang Mai University, Chiang Mai 50100, Thailand
- Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai 50100, Thailand
- Elephant, Wildlife and Companion Animal Research Group, Chiang Mai University, Chiang Mai 50100, Thailand
| | - Kidsadagon Pringproa
- Center of Elephant and Wildlife Health, Chiang Mai University, Chiang Mai 50100, Thailand
- Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai 50100, Thailand
- Elephant, Wildlife and Companion Animal Research Group, Chiang Mai University, Chiang Mai 50100, Thailand
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DETECTION OF ELEPHANT ENDOTHELIOTROPIC HERPESVIRUS 1A IN ARCHIVAL TISSUE USING RNASCOPE ® IN SITU HYBRIDIZATION. J Zoo Wildl Med 2023; 53:661-669. [PMID: 36640067 DOI: 10.1638/2022-0042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/13/2022] [Indexed: 01/09/2023] Open
Abstract
Hemorrhagic disease due to elephant endotheliotropic herpesvirus infection (EEHV-HD) is an important cause of calf mortality in managed and free-ranging Asian (Elephas maximus) and African elephant (Loxodonta spp.) populations. Consequently, infection has profound implications for elephant population growth and sustainability. The mechanisms of disease caused by EEHV (i.e., infection, dissemination, shedding, latency) are relatively undefined, in part because of a lack of robust validated assays for detecting viral gene products in relevant samples. To address this issue, we used RNAscope® in situ hybridization (ISH) based on EEHV1A DNA polymerase and terminase genes to detect EEHV1A RNA in archival formalin-fixed, paraffin-embedded Asian elephant heart and tongue from PCR-confirmed cases (n = 4) of EEHV-HD and Asian elephants (n = 2) that died from other causes. EEHV1A-positive cases had positive hybridization signal in endothelial cell nuclei of both tissues for both DNA polymerase and terminase. EEHV-negative cases lacked signal. In positive cases, the number of positive nuclei was manually assessed to provide an estimate of the viral load and compare sensitivity of the two probes. In all cases, heart had greater signal than tongue for both probes (Wilcoxon rank test; P ≤ 0.01). Overall, terminase hybridization signal was greater than DNA polymerase signal (Wilcoxon rank test; P ≤ 0.01). Results indicate RNAscope ISH is a valuable tool for detection of EEHV in archival samples and for confirming infection. Additionally, the terminase gene is the optimal target and heart is preferable to tongue for detection in cases of EEHV-HD. Results will inform future investigations of viral tropism in EEHV-HD cases due to EEHV1A.
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Pursell T, Spencer Clinton JL, Tan J, Peng R, Ling PD. Modified vaccinia Ankara expressing EEHV1A glycoprotein B elicits humoral and cell-mediated immune responses in mice. PLoS One 2022; 17:e0265424. [PMID: 35312707 PMCID: PMC8936464 DOI: 10.1371/journal.pone.0265424] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2021] [Accepted: 03/01/2022] [Indexed: 12/15/2022] Open
Abstract
Elephant endotheliotropic herpesvirus (EEHV) can cause lethal hemorrhagic disease (EEHV-HD) in Asian elephants and is the largest cause of death in captive juvenile Asian elephants in North America and Europe. EEHV-HD also has been documented in captive and wild elephants in their natural range countries. A safe and effective vaccine to prevent lethal EEHV infection would significantly improve conservation efforts for this endangered species. Recent studies from our laboratory suggest that EEHV morbidity and mortality are often associated with primary infection. Therefore, we aim to generate a vaccine, particularly for EEHV1 naïve animals, with the goal of preventing lethal EEHV-HD. To address this goal, we generated a Modified Vaccinia Ankara (MVA) recombinant virus expressing a truncated form of glycoprotein B (gBΔfur731) from EEHV1A, the strain associated with the majority of lethal EEHV cases. Vaccination of CD-1 mice with this recombinant virus induced robust antibody and polyfunctional T cell responses significantly above mice inoculated with wild-type MVA. Although the vaccine-induced T cell response was mainly observed in CD8+ T cell populations, the CD4+ T cell response was also polyfunctional. No adverse responses to vaccination were observed. Overall, our data demonstrates that MVA-gBΔfur731 stimulates robust humoral and cell-mediated responses, supporting its potential translation for use in elephants.
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Affiliation(s)
- Taylor Pursell
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas, United States of America
| | - Jennifer L. Spencer Clinton
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas, United States of America
| | - Jie Tan
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas, United States of America
| | - Rongsheng Peng
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas, United States of America
| | - Paul D. Ling
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas, United States of America
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NOVEL DIAGNOSTIC AND THERAPEUTIC APPROACHES TO ELEPHANT ENDOTHELIOTROPIC HERPESVIRUS 1A HEMORRHAGIC DISEASE IN A CAPTIVE JUVENILE ASIAN ELEPHANT (ELEPHAS MAXIMUS). J Zoo Wildl Med 2022; 53:232-240. [DOI: 10.1638/2021-0096] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/19/2021] [Indexed: 11/21/2022] Open
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Effects of between and within Herd Moves on Elephant Endotheliotropic Herpesvirus (EEHV) Recrudescence and Shedding in Captive Asian Elephants (Elephas maximus). Viruses 2022; 14:v14020229. [PMID: 35215824 PMCID: PMC8877707 DOI: 10.3390/v14020229] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Revised: 01/18/2022] [Accepted: 01/18/2022] [Indexed: 02/01/2023] Open
Abstract
Haemorrhagic disease associated with elephant endotheliotropic herpesvirus (Elephantid herpesvirus, EEHV) infections is the leading cause of death for Asian elephant (Elephas maximus) calves. This study assessed the effect of captive herd management on EEHV shedding, as evidence of latent infection reactivation, focusing on: (1) the influence of social change on the odds of recrudescence; (2) the respective effects of between and within herd moves; and (3) characteristics of recrudescent viral shedding. Trunk and conjunctival swabs (n = 165) were obtained from six elephants at an EAZA-accredited zoo, collected during a period of social stability, and at times of social change. Longitudinal sampling took place at times of moving two bulls out of the collection and one new bull into an adjacent enclosure to the cow herd (between herd moves), and during a period of mixing this new bull with the cow herd to facilitate mating (within herd moves). Quantitative PCR was employed to detect EEHV 1a/b, 4a/b, and EF–1–α (housekeeping gene). Generalised estimating equations determined EEHV recrudescence odds ratios (OR) and relative viral DNA load. Sixteen EEHV 1a/b shedding events occurred, but no EEHV 4a/b was detected. All management-derived social changes promoted recrudescence (social change OR = 3.27, 95% CI = 0.412–26, p = 0.262; and between herd moves OR = 1.6, 95% CI = 0.178−14.4, p = 0.675), though within herd movements posed the most significant increase of EEHV reactivation odds (OR = 6.86, 95% CI = 0.823−57.1, p = 0.075) and demonstrated the strongest relative influence (post hoc Tukey test p = 0.0425). Shedding onset and magnitude ranged from six to 54 days and from 3.59 to 11.09 ΔCts. Differing challenges are associated with between and within herd movements, which can promote recrudescence and should be considered an exposure risk to naïve elephants.
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Patterns of serum immune biomarkers during elephant endotheliotropic herpesvirus viremia in Asian and African elephants. PLoS One 2021; 16:e0252175. [PMID: 34793450 PMCID: PMC8601435 DOI: 10.1371/journal.pone.0252175] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2021] [Accepted: 11/02/2021] [Indexed: 12/23/2022] Open
Abstract
Hemorrhagic disease (HD) caused by a group of elephant endotheliotropic herpesviruses (EEHV) is one of the leading causes of death for young elephants in human care. These viruses are widespread and typically persist latently in adult elephants with no negative effects; however, in juvenile Asian and more recently young African elephants, the onset of disease can be rapid and the mortality rate high. Measuring biomarkers associated with the immune response could be beneficial to understanding underlying disease processes, as well as the management of infection and HD. The goal of this study was to measure acute phase proteins and cytokines in serum collected from elephants infected with EEHV (13 Asian and 1 African) and compare concentrations according to presence, severity and outcome of disease. Serum amyloid A (SAA) and haptoglobin (HP) were higher in elephants with EEHV viremia than those without; concentrations increased with increasing viral load, and were higher in fatal cases compared to those that survived. In Asian elephants, SAA was also higher during EEHV1 viremia compared to EEHV5. Cytokine concentrations were typically low, and no statistical differences existed between groups. However, in individuals with detectable levels, longitudinal profiles indicated changes in tumor necrosis factor alpha (TNF-α) and interleukin-2 (IL-2) that may reflect an immune response to EEHV infection. However, the overall low concentrations detected using previously validated assays do not support the presence of a 'cytokine storm' and suggest more work is needed to understand if sub-optimal immune responses could be involved in disease progression. These results highlight the potential benefit of measuring circulating biomarker concentrations, such as APPs and cytokines, to improve our understanding of EEHV viremia and HD, assist with monitoring the progression of disease and determining the impact of interventions.
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Primary Infection May Be an Underlying Factor Contributing to Lethal Hemorrhagic Disease Caused by Elephant Endotheliotropic Herpesvirus 3 in African Elephants ( Loxodonta africana). Microbiol Spectr 2021; 9:e0098321. [PMID: 34668724 PMCID: PMC8528115 DOI: 10.1128/spectrum.00983-21] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Distinct but related species of elephant endotheliotropic herpesviruses (EEHVs) circulate within Asian and African elephant populations. Primary infection with EEHVs endemic among Asian elephants can cause clinical illness and lethal EEHV hemorrhagic disease (EEHV-HD). The degree to which this occurs among African elephants has not been fully established. Recent cases of EEHV-HD caused by the EEHV3 species in African elephants housed in North American zoos has heightened concern about the susceptibility of this elephant species to EEHV-HD. In this study, we utilize the luciferase immunoprecipitation system (LIPS) to generate a serological assay specific for EEHV3 in African elephants by detecting antibodies against the EEHV3 E34 protein. The results showed that the majority of tested elephants from four separate and genetically unrelated herds, including five elephants that survived clinical illness associated with EEHV3, were positive for prior infection with EEHV3. However, African elephants who succumbed to EEHV3-HD were seronegative for EEHV3 prior to lethal infection. This supports the hypothesis that fatal EEHV-HD caused by EEHV3 is associated with primary infection rather than reactivation of latent virus. Lastly, we observed that African elephants, like Asian elephants, acquire abundant anti-EEHV antibodies prenatally and that anti-EEHV3 specific antibodies were either never detected or declined to undetectable levels in those animals that died from lethal disease following EEHV3 infection. IMPORTANCE Prior to 2019, only five cases of clinical disease from EEHV infection among African elephants had been documented. Since 2019, there have been at least seven EEHV-HD cases in North American zoos, resulting in three fatalities, all associated with EEHV3. Evidence is accumulating to suggest that EEHV-associated clinical illness and death among Asian elephants is due to primary infection and may be associated with waning anti-EEHV antibody levels in young elephants. The development of the EEHV3 serological test described in this study enabled us to confirm that similar dynamics may be contributing to EEHV-HD in African elephants. The ability to screen for EEHV immune status in African elephant calves will have a major impact on managing captive African elephant herds and will provide new tools for investigating and understanding EEHV in wild populations.
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Yun Y, Sripiboon S, Pringproa K, Chuammitri P, Punyapornwithaya V, Boonprasert K, Tankaew P, Angkawanish T, Namwongprom K, Arjkumpa O, Brown JL, Thitaram C. Clinical characteristics of elephant endotheliotropic herpesvirus (EEHV) cases in Asian elephants ( Elephas maximus) in Thailand during 2006-2019. Vet Q 2021; 41:268-279. [PMID: 34511026 PMCID: PMC8475116 DOI: 10.1080/01652176.2021.1980633] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Background Elephant endotheliotropic herpesvirus causes a hemorrhagic disease (EEHV-HD) that is a major cause of death in juvenile Asian elephants with EEHV1 and EEHV4 being the most prevalent. Aim To perform a retrospective clinical data analysis. Methods Records of a total of 103 cases in Thailand confirmed by polymerase chain reaction (PCR) on blood and/or tissue samples. Results The severity of clinical signs varied among EEHV subtypes. EEHV1A was the most prevalent with 58%, followed by EEHV4 with 34%, EEHV1B with 5.8% and EEHV1&4 co-infection with 1.9%. Overall case fatality rate was 66%. When compared among subtypes, 100% case fatality rate was associated with EEHV1&4 co-infection, 83% with EEHV1B, 75% with EEHV1A, and the lowest at 40% for EEHV4. Calves 2- to 4-year old were in the highest age risk group and exhibited more severe clinical signs with the highest mortality. Majority of cases were found in weaned or trained claves and higher number of cases were observed in rainy season. A gender predilection could not be demonstrated. Severely affected elephants presented with thrombocytopenia, depletion of monocytes, lymphocytes and heterophils, a monocyte:heterophil (M:H) ratio lower than 2.37, hypoproteinemia (both albumin and globulin), severe grade of heterophil toxicity, and low red blood cell counts and pack cell volumes. Survival was not affected by antiviral drug treatment in the severely compromised animals. Conclusion Early detection by laboratory testing and aggressive application of therapies comprising of supportive and anti-viral treatment can improve survival outcomes of this disease.
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Affiliation(s)
- Yaoprapa Yun
- Faculty of Veterinary Medicine, Center of Elephant and Wildlife Research, Chiang Mai University (FVM-CMU), Chiang Mai, Thailand.,Graduate Program in Veterinary Science, Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai, Thailand
| | - Supaphen Sripiboon
- Faculty of Veterinary Medicine, Department of Large Animal and Wildlife Clinical Sciences, Kasetsart University (FVM-KU), Kamphaeng Saen Campus, Nakornpathom, Thailand
| | - Kidsadagon Pringproa
- Faculty of Veterinary Medicine, Department of Veterinary Biosciences and Public Health, Chiang Mai University, Chiang Mai, Thailand
| | - Phongsakorn Chuammitri
- Faculty of Veterinary Medicine, Department of Veterinary Biosciences and Public Health, Chiang Mai University, Chiang Mai, Thailand
| | - Veerasak Punyapornwithaya
- Faculty of Veterinary Medicine, Veterinary Public Health and Food Safety Centre for Asia Pacific, Chiang Mai University, Chiang Mai, Thailand
| | - Khajohnpat Boonprasert
- Faculty of Veterinary Medicine, Center of Elephant and Wildlife Research, Chiang Mai University (FVM-CMU), Chiang Mai, Thailand
| | - Pallop Tankaew
- Faculty of Veterinary Medicine, Center of Elephant and Wildlife Research, Chiang Mai University (FVM-CMU), Chiang Mai, Thailand
| | - Taweepoke Angkawanish
- Elephant Hospital, National Elephant Institute (NEI), Forest Industry Organization, Lampang, Thailand
| | - Kittikul Namwongprom
- Elephant Hospital, National Elephant Institute (NEI), Forest Industry Organization, Lampang, Thailand
| | - Orapun Arjkumpa
- Phra Nakhon Si Ayutthaya Provincial Livestock Office, Phra Nakhon Si Ayutthaya Province, Thailand
| | - Janine L Brown
- Faculty of Veterinary Medicine, Center of Elephant and Wildlife Research, Chiang Mai University (FVM-CMU), Chiang Mai, Thailand.,Center for Species Survival, Smithsonian Conservation Biology Institute (SCBI), Front Royal, VA, USA
| | - Chatchote Thitaram
- Faculty of Veterinary Medicine, Center of Elephant and Wildlife Research, Chiang Mai University (FVM-CMU), Chiang Mai, Thailand.,Department of Companion Animal and Wildlife Clinics, Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai, Thailand
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12
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Common SM, Yun Y, Silva-Fletcher A, Thitaram C, Janyamethakul T, Khammesri S, Molenaar FM. Developing a non-invasive method of detecting elephant endotheliotropic herpesvirus infections using faecal samples. Vet Rec 2021; 190:e833. [PMID: 34472109 DOI: 10.1002/vetr.833] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Revised: 06/07/2021] [Accepted: 07/27/2021] [Indexed: 02/06/2023]
Abstract
BACKGROUND Elephant endotheliotropic herpesvirus (EEHV)-associated haemorrhagic disease (EEHV-HD) is a leading cause of death in Asian elephant calves across the world. Cases of EEHV-HD have been detected in free-living calves through post-mortem examination (PME) indicating the presence of the virus in the wild. In the absence of a non-invasive sampling method, little research into free-living populations has been possible. This study aimed to provide evidence that faeces can be used as a non-invasive sampling method for the detection of EEHV excretion using quantitative polymerase chain reaction. METHODS Serial saliva swabs and faecal samples were taken from five captive Asian elephants in Thailand over 12 weeks. To ensure the presence of detectable elephant DNA within the sample, qPCR was run for amplification of the Asian elephant tumour necrosis factor (TNF-α) gene, EEHV1 and EEHV4. RESULTS Of 28 sample pairs, seven saliva samples were positive for EEHV, of which two had paired positive faecal samples. CONCLUSIONS This study presents the first evidence that EEHV is excreted in faeces at detectable levels. This method may in future be used for improved understanding of the epidemiology of EEHV in free-living elephant populations, as well as detection of EEHV excretion in captive herds.
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Affiliation(s)
- Sophie M Common
- Institute of Zoology, Zoological Society of London, Regents Park, London, NW8 7LS, UK.,The Royal Veterinary College, Hatfield, Hertfordshire, UK
| | - Yaoprapa Yun
- Center of Elephant and Wildlife Research, Faculty of Veterinary Medicine, Chiang Mai University (FVM-CMU), Chiang Mai, Thailand
| | | | - Chatchote Thitaram
- Center of Elephant and Wildlife Research, Faculty of Veterinary Medicine, Chiang Mai University (FVM-CMU), Chiang Mai, Thailand
| | | | - Siripat Khammesri
- Center of Elephant and Wildlife Research, Faculty of Veterinary Medicine, Chiang Mai University (FVM-CMU), Chiang Mai, Thailand
| | - Fieke M Molenaar
- Whipsnade Zoo, Zoological Society of London, Dunstable, Bedfordshire, UK
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13
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Perrin KL, Kristensen AT, Bertelsen MF, Denk D. Retrospective review of 27 European cases of fatal elephant endotheliotropic herpesvirus-haemorrhagic disease reveals evidence of disseminated intravascular coagulation. Sci Rep 2021; 11:14173. [PMID: 34238966 PMCID: PMC8266883 DOI: 10.1038/s41598-021-93478-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2021] [Accepted: 06/25/2021] [Indexed: 02/06/2023] Open
Abstract
Elephant endotheliotropic herpesvirus haemorrhagic disease (EEHV-HD) is widely acknowledged as the most common cause of mortality in young Asian elephants (Elephas maximus) in captivity. The objective of the current study was to perform a blinded, retrospective pathology review of European EEHV-HD fatalities, constituting the largest systematic assessment of EEHV-HD pathology to date. Findings between viral genotypes were compared with the aim to investigate if disseminated intravascular coagulation (DIC) could be substantiated as a significant complicating factor, thereby increasing the understanding of disease pathophysiology. Immunohistochemical staining confirmed endothelial cell (EC) damage and the presence of EC intranuclear inclusion bodies, demonstrating a direct viral cytopathic effect. Microthrombi were observed in 63% of cases in several organs, including lungs, which, together with widespread haemorrhage and thrombocytopenia reported in EEHV-HD case reports, supports the presence of overt DIC as a serious haemostatic complication of active EEHV infection. Death was attributed to widespread vascular damage with multi-organ dysfunction, including severe acute myocardial haemorrhage and subsequent cardiac failure. Systemic inflammation observed in the absence of bacterial infection may be caused by cytokine release syndrome. Findings reinforce the necessity to investigate cytokine responses and haemostatic status during symptomatic and asymptomatic EEHV viraemia, to potentially support the use of anti-inflammatory treatment in conjunction with anti-viral therapy and cardiovascular support.
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Affiliation(s)
- K L Perrin
- Center for Zoo and Wild Animal Health, Copenhagen Zoo, Roskildevej 38, 2000, Frederiksberg, Denmark.
- The Department of Veterinary Clinical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Dyrlægevej 16, 1870, Frederiksberg, Denmark.
| | - A T Kristensen
- The Department of Veterinary Clinical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Dyrlægevej 16, 1870, Frederiksberg, Denmark
| | - M F Bertelsen
- Center for Zoo and Wild Animal Health, Copenhagen Zoo, Roskildevej 38, 2000, Frederiksberg, Denmark
| | - D Denk
- International Zoo Veterinary Group, Station House, Parkwood Street, Keighley, BD21 4NQ, UK
- Institute for Animal Pathology, Ludwig-Maximilians-University, Veterinärstr. 13, 80539, Munich, Germany
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14
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Pathogenesis of hemorrhagic disease caused by elephant endotheliotropic herpesvirus (EEHV) in Asian elephants (Elephas maximus). Sci Rep 2021; 11:12998. [PMID: 34155304 PMCID: PMC8217522 DOI: 10.1038/s41598-021-92393-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Accepted: 06/10/2021] [Indexed: 02/06/2023] Open
Abstract
Elephant endotheliotropic herpesvirus-hemorrhagic disease (EEHV-HD) is an acute fatal disease in elephants. Despite the fact that the underlying pathogenesis of EEHV-HD has been proposed, it remains undetermined as to what mechanisms drive these hemorrhagic and edematous lesions. In the present study, we have investigated and explained the pathogenesis of acute EEHV-HD using blood profiles of EEHV-HD and EEHV-infected cases, hematoxylin and eosin (H&E) stain, special stains, immunohistochemistry, quantitative polymerase chain reaction (PCR) and reverse transcriptase polymerase chain reaction (RT-PCR). It was found that EEHV genomes were predominantly detected in various internal organs of EEHV-HD cases. Damage to endothelial cells, vasculitis and vascular thrombosis of the small blood vessels were also predominantly observed. Increases in platelet endothelial cell adhesion molecules-1 (PECAM-1)- and von Willebrand factor (vWF)-immunolabeling positive cells were significantly noticed in injured blood vessels. The expression of pro-inflammatory cytokine mRNA was significantly up-regulated in EEHV-HD cases when compared to EEHV-negative controls. We have hypothesized that this could be attributed to the systemic inflammation and disruption of small blood vessels, followed by the disseminated intravascular coagulopathy that enhanced hemorrhagic and edematous lesions in EEHV-HD cases. Our findings have brought attention to the potential application of effective preventive and therapeutic protocols to treat EEHV infection in Asian elephants.
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15
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Oo ZM, Aung YH, Aung TT, San N, Tun ZM, Hayward GS, Zachariah A. Elephant Endotheliotropic Herpesvirus Hemorrhagic Disease in Asian Elephant Calves in Logging Camps, Myanmar. Emerg Infect Dis 2021; 26:63-69. [PMID: 31855135 PMCID: PMC6924905 DOI: 10.3201/eid2601.190159] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
In recent years, an alarming number of cases of lethal acute hemorrhagic disease have occurred in Asian elephant calves raised in logging camps in Myanmar. To determine whether these deaths were associated with infection by elephant endotheliotropic herpesvirus (EEHV), we conducted diagnostic PCR subtype DNA sequencing analysis on necropsy tissue samples collected from 3 locations. We found that EEHV DNA from 7 PCR loci was present at high levels in all 3 calves and was the same EEHV1A virus type that has been described in North America, Europe, and other parts of Asia. However, when analyzed over 5,610 bp, the strains showed major differences from each other and from all previously characterized EEHV1A strains. We conclude that these 3 elephant calves in Myanmar died from the same herpesvirus disease that has afflicted young Asian elephants in other countries over the past 20 years.
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16
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Pearson VR, Bosse JB, Koyuncu OO, Scherer J, Toruno C, Robinson R, Abegglen LM, Schiffman JD, Enquist LW, Rall GF. Identification of African Elephant Polyomavirus in wild elephants and the creation of a vector expressing its viral tumor antigens to transform elephant primary cells. PLoS One 2021; 16:e0244334. [PMID: 33544724 PMCID: PMC7864673 DOI: 10.1371/journal.pone.0244334] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Accepted: 12/07/2020] [Indexed: 11/29/2022] Open
Abstract
Wild elephant populations are declining rapidly due to rampant killing for ivory and body parts, range fragmentation, and human-elephant conflict. Wild and captive elephants are further impacted by viruses, including highly pathogenic elephant endotheliotropic herpesviruses. Moreover, while the rich genetic diversity of the ancient elephant lineage is disappearing, elephants, with their low incidence of cancer, have emerged as a surprising resource in human cancer research for understanding the intrinsic cellular response to DNA damage. However, studies on cellular resistance to transformation and herpesvirus reproduction have been severely limited, in part due to the lack of established elephant cell lines to enable in vitro experiments. This report describes creation of a recombinant plasmid, pAelPyV-1-Tag, derived from a wild isolate of African Elephant Polyomavirus (AelPyV-1), that can be used to create immortalized lines of elephant cells. This isolate was extracted from a trunk nodule biopsy isolated from a wild African elephant, Loxodonta africana, in Botswana. The AelPyV-1 genome contains open-reading frames encoding the canonical large (LTag) and small (STag) tumor antigens. We cloned the entire early region spanning the LTag and overlapping STag genes from this isolate into a high-copy vector to construct a recombinant plasmid, pAelPyV-1-Tag, which effectively transformed primary elephant endothelial cells. We expect that the potential of this reagent to transform elephant primary cells will, at a minimum, facilitate study of elephant-specific herpesviruses.
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Affiliation(s)
- Virginia R. Pearson
- Fox Chase Cancer Center, Program in Blood Cell Development and Function, Philadelphia, Pennsylvania, United States of America
- * E-mail:
| | - Jens B. Bosse
- RESIST Cluster of Excellence, Institute of Virology at Hannover Medical School, Center for Structural Systems Biology, Hamburg, Germany
- Heinrich Pette Institute, Leibniz Institute for Experimental Virology, Hamburg, Germany
| | - Orkide O. Koyuncu
- Princeton University, Department of Molecular Biology, Princeton, New Jersey, United States of America
| | - Julian Scherer
- Princeton University, Department of Molecular Biology, Princeton, New Jersey, United States of America
| | - Cristhian Toruno
- Huntsman Cancer Institute, University of Utah, Salt Lake City, Utah, United States of America
| | - Rosann Robinson
- Huntsman Cancer Institute, University of Utah, Salt Lake City, Utah, United States of America
| | - Lisa M. Abegglen
- Huntsman Cancer Institute, University of Utah, Salt Lake City, Utah, United States of America
| | - Joshua D. Schiffman
- Huntsman Cancer Institute, University of Utah, Salt Lake City, Utah, United States of America
| | - Lynn W. Enquist
- Princeton University, Department of Molecular Biology, Princeton, New Jersey, United States of America
| | - Glenn F. Rall
- Fox Chase Cancer Center, Program in Blood Cell Development and Function, Philadelphia, Pennsylvania, United States of America
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17
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Dhingra A, Götting J, Varanasi PR, Steinbrueck L, Camiolo S, Zischke J, Heim A, Schulz TF, Weissinger EM, Kay-Fedorov PC, Davison AJ, Suárez NM, Ganzenmueller T. Human cytomegalovirus multiple-strain infections and viral population diversity in haematopoietic stem cell transplant recipients analysed by high-throughput sequencing. Med Microbiol Immunol 2021; 210:291-304. [PMID: 34611744 PMCID: PMC8541999 DOI: 10.1007/s00430-021-00722-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Accepted: 09/21/2021] [Indexed: 01/22/2023]
Abstract
Human cytomegalovirus (HCMV) is an important opportunistic pathogen in allogeneic haematopoietic stem cell transplant (HSCT) recipients. High-throughput sequencing of target-enriched libraries was performed to characterise the diversity of HCMV strains present in this high-risk group. Forty-four HCMV-DNA-positive plasma specimens (median viral input load 321 IU per library) collected at defined time points from 23 HSCT recipients within 80 days of transplantation were sequenced. The genotype distribution for 12 hypervariable HCMV genes and the number of HCMV strains present (i.e. single- vs. multiple-strain infection) were determined for 29 samples from 16 recipients. Multiple-strain infection was observed in seven of these 16 recipients, and five of these seven recipients had the donor (D)/recipient (R) HCMV-serostatus combination D + R + . A very broad range of genotypes was detected, with an intrahost composition that was generally stable over time. Multiple-strain infection was not associated with particular virological or clinical features, such as altered levels or duration of antigenaemia, development of acute graft-versus-host disease or increased mortality. In conclusion, despite relatively low viral plasma loads, a high frequency of multiple-strain HCMV infection and a high strain complexity were demonstrated in systematically collected clinical samples from this cohort early after HSCT. However, robust evaluation of the pathogenic role of intrahost viral diversity and multiple-strain infection will require studies enrolling larger numbers of recipients.
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Affiliation(s)
- A. Dhingra
- Hannover Medical School, Institute of Virology, Hannover, Germany ,German Center for Infection Research (DZIF), Site Hannover-Braunschweig, Hannover, Germany
| | - J. Götting
- Hannover Medical School, Institute of Virology, Hannover, Germany ,German Center for Infection Research (DZIF), Site Hannover-Braunschweig, Hannover, Germany
| | - P. R. Varanasi
- German Center for Infection Research (DZIF), Site Hannover-Braunschweig, Hannover, Germany ,Department of Haematology, Haemostasis and Oncology, Hannover Medical School, Hannover, Germany ,Present Address: National Centre for Biological Sciences, Bangalore, India
| | - L. Steinbrueck
- Hannover Medical School, Institute of Virology, Hannover, Germany ,German Center for Infection Research (DZIF), Site Hannover-Braunschweig, Hannover, Germany
| | - S. Camiolo
- MRC-University of Glasgow Centre for Virus Research, Glasgow, UK
| | - J. Zischke
- Hannover Medical School, Institute of Virology, Hannover, Germany ,German Center for Infection Research (DZIF), Site Hannover-Braunschweig, Hannover, Germany
| | - A. Heim
- Hannover Medical School, Institute of Virology, Hannover, Germany ,German Center for Infection Research (DZIF), Site Hannover-Braunschweig, Hannover, Germany
| | - T. F. Schulz
- Hannover Medical School, Institute of Virology, Hannover, Germany ,German Center for Infection Research (DZIF), Site Hannover-Braunschweig, Hannover, Germany
| | - E. M. Weissinger
- German Center for Infection Research (DZIF), Site Hannover-Braunschweig, Hannover, Germany ,Department of Haematology, Haemostasis and Oncology, Hannover Medical School, Hannover, Germany
| | - P. C. Kay-Fedorov
- Hannover Medical School, Institute of Virology, Hannover, Germany ,German Center for Infection Research (DZIF), Site Hannover-Braunschweig, Hannover, Germany
| | - A. J. Davison
- MRC-University of Glasgow Centre for Virus Research, Glasgow, UK
| | - N. M. Suárez
- MRC-University of Glasgow Centre for Virus Research, Glasgow, UK
| | - T. Ganzenmueller
- Hannover Medical School, Institute of Virology, Hannover, Germany ,German Center for Infection Research (DZIF), Site Hannover-Braunschweig, Hannover, Germany ,Institute for Medical Virology and Epidemiology, University Hospital Tuebingen, Elfriede-Aulhorn-Str. 6, 72076 Tuebingen, Germany
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18
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Photichai K, Guntawang T, Sittisak T, Kochagul V, Chuammitri P, Thitaram C, Thananchai H, Chewonarin T, Sringarm K, Pringproa K. Attempt to Isolate Elephant Endotheliotropic Herpesvirus (EEHV) Using a Continuous Cell Culture System. Animals (Basel) 2020; 10:E2328. [PMID: 33297581 PMCID: PMC7762348 DOI: 10.3390/ani10122328] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2020] [Revised: 11/28/2020] [Accepted: 12/04/2020] [Indexed: 11/17/2022] Open
Abstract
Elephant endotheliotropic herpesvirus (EEHV) infection is known to cause acute fatal hemorrhagic disease, which has killed many young Asian elephants (Elephas maximus). Until recently, in vitro isolation and propagation of the virus have not been successful. This study aimed to isolate and propagate EEHV using continuous cell lines derived from human and/or animal origins. Human cell lines, including EA. hy926, A549, U937, RKO, SW620, HCT-116 and HT-29, and animal cell lines, including CT26.CL25 and sp2/0-Ag14, were investigated in this study. Mixed frozen tissue samples of the heart, lung, liver, spleen and kidney obtained from fatal EEHV1A- or EEHV4-infected cases were homogenized and used for cell inoculation. At 6, 24, 48 and 72 h post infection (hpi), EEHV-inoculated cells were observed for cytopathic effects (CPEs) or were assessed for EEHV infection by immunoperoxidase monolayer assay (IPMA) or quantitative PCR. The results were then compared to those of the mock-infected controls. Replication of EEHV in the tested cells was further determined by immunohistochemistry of cell pellets using anti-EEHV DNA polymerase antibodies or re-inoculated cells with supernatants obtained from passages 2 or 3 of the culture medium. The results reveal that no CPEs were observed in the tested cells, while immunolabeling for EEHV gB was observed in only U937 human myeloid leukemia cells. However, quantitation values of the EEHV terminase gene, as well as those of the EEHV gB or EEHV DNA polymerase proteins in U937 cells, gradually declined from passage 1 to passage 3. The findings of this study indicate that despite poor adaptation in U937 cells, this cell line displays promise and potential to be used for the isolation of EEHV1 and EEHV4 in vitro.
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Affiliation(s)
- Kornravee Photichai
- Department of Veterinary Biosciences and Veterinary Public Health, Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai 50100, Thailand; (K.P.); (T.G.); (T.S.); (P.C.)
| | - Thunyamas Guntawang
- Department of Veterinary Biosciences and Veterinary Public Health, Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai 50100, Thailand; (K.P.); (T.G.); (T.S.); (P.C.)
| | - Tidaratt Sittisak
- Department of Veterinary Biosciences and Veterinary Public Health, Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai 50100, Thailand; (K.P.); (T.G.); (T.S.); (P.C.)
| | - Varankpicha Kochagul
- Veterinary Diagnostic Laboratory, Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai 50100, Thailand;
| | - Phongsakorn Chuammitri
- Department of Veterinary Biosciences and Veterinary Public Health, Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai 50100, Thailand; (K.P.); (T.G.); (T.S.); (P.C.)
| | - Chatchote Thitaram
- Department of Companion Animals and Wildlife Clinics, Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai 50100, Thailand;
| | - Hathairat Thananchai
- Department of Microbiology, Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand;
| | - Teera Chewonarin
- Department of Biochemistry, Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand;
| | - Korawan Sringarm
- Department of Animal and Aquatic Sciences, Faculty of Agriculture, Chiang Mai University, Chiang Mai 50200, Thailand;
| | - Kidsadagon Pringproa
- Department of Veterinary Biosciences and Veterinary Public Health, Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai 50100, Thailand; (K.P.); (T.G.); (T.S.); (P.C.)
- Excellence Center in Veterinary Bioscience, Chiang Mai University, Chiang Mai 50100, Thailand
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19
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In vivo characterization of target cells for acute elephant endotheliotropic herpesvirus (EEHV) infection in Asian elephants (Elephas maximus). Sci Rep 2020; 10:11402. [PMID: 32647124 PMCID: PMC7347588 DOI: 10.1038/s41598-020-68413-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2020] [Accepted: 06/24/2020] [Indexed: 12/16/2022] Open
Abstract
Elephant endotheliotropic herpesvirus-hemorrhagic disease (EEHV-HD) is a dangerous viral infectious disease in young Asian elephants. Despite hypotheses underlying pathogenesis of the disease, it is unclear which cell types the virus targets during acute or persistent infections. This study investigated the tissues and target cells permissive for EEHV infection and replication in vivo. Rabbit polyclonal antibodies against the non-structural proteins of EEHV, DNA polymerase (EEHV DNAPol), were generated and validated. These were used to examine EEHV infection and replication in various tissues of acute EEHV-HD cases and compared to an EEHV-negative control. The results indicated that viral antigens were distributed throughout the epithelia of the alimentary tract and salivary glands, endothelia and smooth muscle cells, and monocytic lineage cells of the EEHV-infected elephants. Moreover, EEHV DNAPol proteins were also found in the bone marrow cells of the EEHV1A-HD and EEHV1A/4-HD cases. This study demonstrated for the first time the target cells that favor in vivo EEHV replication during acute infection, providing a promising foundation for investigating EEHV propagation in vitro.
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20
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Lethal Hemorrhagic Disease and Clinical Illness Associated with Elephant Endotheliotropic Herpesvirus 1 Are Caused by Primary Infection: Implications for the Detection of Diagnostic Proteins. J Virol 2020; 94:JVI.01528-19. [PMID: 31723022 PMCID: PMC7000966 DOI: 10.1128/jvi.01528-19] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2019] [Accepted: 10/17/2019] [Indexed: 12/21/2022] Open
Abstract
Whether clinical illness and deaths associated with elephant endotheliotropic herpesvirus (EEHV) infection result from primary infection or reactivation of latent virus is a longstanding question in the field. By applying a relatively new assay, the luciferase immunoprecipitation system (LIPS), combined with the genomic sequences of the viruses, we gained the insights and tools needed to resolve this issue. Our EEHV1-specific LIPS assay should be useful for assessing the vulnerability of elephant calves to infection with different EEHVs and evaluating antibody responses to anti-EEHV vaccines. A significant proportion of the Asian elephant population is under some form of human care. Hence, the ability to screen for EEHV immune status in elephant calves should have a major impact on the management of these animals worldwide. Elephant endotheliotropic herpesvirus (EEHV) can cause lethal hemorrhagic disease in juvenile Asian elephants, both in captivity and in the wild. Most deaths associated with the virus are caused by two chimeric variants of EEHV1 (EEHV1A and EEHV1B), while two other EEHVs endemic within Asian elephants (EEHV4 and EEHV5) have been recognized but cause death less often. Whether lethal EEHV infections are due to primary infection or reactivation of latent virus remains unknown, and knowledge of the anti-EEHV antibody levels in young elephants is limited. To close these gaps, we sought to develop a serologic assay capable of distinguishing among infections with different EEHVs using a luciferase immunoprecipitation system (LIPS) for antibody profiling and a panel of conserved EEHV recombinant proteins and proteins unique to EEHV1. The results showed that elephants dying from EEHV1 hemorrhagic disease or ill from EEHV infection were seronegative for the EEHV species that caused the disease or illness, indicating that the events were associated with primary infection rather than reactivation of latent virus. We also demonstrated that waning of EEHV1-specific antibodies can occur in the first 2 years of life, when a threshold protective level of antibody may be needed to prevent severe EEHV1-related disease. Use of the LIPS assay to identify putative “diagnostic” proteins would be a valuable asset in determining the EEHV immune status of young elephants and responses to candidate EEHV vaccines in the future. IMPORTANCE Whether clinical illness and deaths associated with elephant endotheliotropic herpesvirus (EEHV) infection result from primary infection or reactivation of latent virus is a longstanding question in the field. By applying a relatively new assay, the luciferase immunoprecipitation system (LIPS), combined with the genomic sequences of the viruses, we gained the insights and tools needed to resolve this issue. Our EEHV1-specific LIPS assay should be useful for assessing the vulnerability of elephant calves to infection with different EEHVs and evaluating antibody responses to anti-EEHV vaccines. A significant proportion of the Asian elephant population is under some form of human care. Hence, the ability to screen for EEHV immune status in elephant calves should have a major impact on the management of these animals worldwide.
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21
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Srivorakul S, Guntawang T, Kochagul V, Photichai K, Sittisak T, Janyamethakul T, Boonprasert K, Khammesri S, Langkaphin W, Punyapornwithaya V, Chuammitri P, Thitaram C, Pringproa K. Possible roles of monocytes/macrophages in response to elephant endotheliotropic herpesvirus (EEHV) infections in Asian elephants (Elephas maximus). PLoS One 2019; 14:e0222158. [PMID: 31491031 PMCID: PMC6730851 DOI: 10.1371/journal.pone.0222158] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Accepted: 08/22/2019] [Indexed: 12/14/2022] Open
Abstract
Elephant endotheliotropic herpesvirus-hemorrhagic disease (EEHV-HD) is the primary cause of acute, highly fatal, hemorrhagic diseases in young Asian elephants. Although monocytopenia is frequently observed in EEHV-HD cases, the role monocytes play in EEHV-disease pathogenesis is unknown. This study seeks to explain the responses of monocytes/macrophages in the pathogenesis of EEHV-HD. Samples of blood, frozen tissues, and formalin-fixed, paraffin-embedded (FFPE) tissues from EEHV1A-HD, EEHV4-HD, co-infected EEHV1A and 4-HD, and EEHV-negative calves were analyzed. Peripheral blood mononuclear cells (PBMCs) from the persistent EEHV4-infected and EEHV-negative calves were also studied. The results showed increased infiltration of Iba-1-positive macrophages in the inflamed tissues of the internal organs of elephant calves with EEHV-HD. In addition, cellular apoptosis also increased in the tissues of elephants with EEHV-HD, especially in the PBMCs, compared to the EEHV-negative control. In the PBMCs of persistent EEHV4-infected elephants, cytokine mRNA expression was high, particularly up-regulation of TNF-α and IFN-γ. Moreover, viral particles were observed in the cytoplasm of the persistent EEHV4-infected elephant monocytes. Our study demonstrated for the first time that apoptosis of the PBMCs increased in cases of EEHV-HD. Furthermore, this study showed that monocytes may serve as a vehicle for viral dissemination during EEHV infection in Asian elephants.
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Affiliation(s)
- Saralee Srivorakul
- Veterinary Diagnostic Laboratory, Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai, Thailand
| | - Thunyamas Guntawang
- Department of Veterinary Biosciences and Veterinary Public Health, Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai, Thailand
| | - Varankpicha Kochagul
- Veterinary Diagnostic Laboratory, Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai, Thailand
| | - Kornravee Photichai
- Veterinary Diagnostic Laboratory, Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai, Thailand
| | - Tidaratt Sittisak
- Department of Veterinary Biosciences and Veterinary Public Health, Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai, Thailand
| | | | - Khajohnpat Boonprasert
- Center of Excellence in Elephant and Wildlife Research, Chiang Mai University, Chiang Mai, Thailand
| | | | | | - Veerasak Punyapornwithaya
- Department of Food Animal Clinic, Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai, Thailand
| | - Phongsakorn Chuammitri
- Department of Veterinary Biosciences and Veterinary Public Health, Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai, Thailand
| | - Chatchote Thitaram
- Center of Excellence in Elephant and Wildlife Research, Chiang Mai University, Chiang Mai, Thailand.,Department of Companion Animals and Wildlife Clinics, Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai, Thailand
| | - Kidsadagon Pringproa
- Department of Veterinary Biosciences and Veterinary Public Health, Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai, Thailand.,Center of Excellence in Elephant and Wildlife Research, Chiang Mai University, Chiang Mai, Thailand
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22
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Boonprasert K, Punyapornwithaya V, Tankaew P, Angkawanish T, Sriphiboon S, Titharam C, Brown JL, Somgird C. Survival analysis of confirmed elephant endotheliotropic herpes virus cases in Thailand from 2006 - 2018. PLoS One 2019; 14:e0219288. [PMID: 31276571 PMCID: PMC6611605 DOI: 10.1371/journal.pone.0219288] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2018] [Accepted: 06/20/2019] [Indexed: 11/19/2022] Open
Abstract
The elephant endotheliotropic herpesvirus (EEHV) has been a known cause of death of young elephants in Thailand for over a decade. In this study, we report on the demography, disease characteristics and mortality of 58 elephants with confirmed EEHV hemorrhagic disease between January 2006 and August 2018 using retrospective data subjected to survival analysis. Median age of EEHV presentation was 29 months, and the mortality rate was 68.97% with a median survival time of 36 h. Most EEHV cases occurred in the north of Thailand, the region where most of the country’s captive elephants reside. The hazard ratio analysis identified application of medical procedures and antiviral medications as being significant factors correlated to the risk of death. Our results indicate a need to focus EEHV monitoring efforts on young elephants and to follow current protocols that advise starting treatments before clinical signs appear.
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Affiliation(s)
| | - Veerasak Punyapornwithaya
- Center of Elephant and Wildlife Research, Chiang Mai University, Chiang Mai, Thailand
- Department of Food Animal Clinic, Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai, Thailand
| | - Pallop Tankaew
- Center of Elephant and Wildlife Research, Chiang Mai University, Chiang Mai, Thailand
| | - Taweepoke Angkawanish
- Elephant Hospital, National Elephant Institute, Forest Industry Organization, Lampang, Thailand
| | - Supaphen Sriphiboon
- Department of Large Animal and Wildlife Clinical Sciences, Faculty of Veterinary Medicine, Kasetsart University, Kamphaeng Saen Campus, Nakornpathom, Thailand
| | - Chatchote Titharam
- Center of Elephant and Wildlife Research, Chiang Mai University, Chiang Mai, Thailand
- Department of Companion Animal and Wildlife Clinics, Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai, Thailand
| | - Janine L. Brown
- Center for Species Survival, Smithsonian Conservation Biology Institute, Front Royal, Virginia, United State of America
| | - Chaleamchat Somgird
- Center of Elephant and Wildlife Research, Chiang Mai University, Chiang Mai, Thailand
- Department of Companion Animal and Wildlife Clinics, Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai, Thailand
- * E-mail:
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23
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ASSESSMENT OF A LANCET-AND-SWAB BLOOD SAMPLING TECHNIQUE FOR SURVEILLANCE OF ELEPHANT ENDOTHELIOTROPIC HERPESVIRUS INFECTION. J Zoo Wildl Med 2019; 48:659-667. [PMID: 28920803 DOI: 10.1638/2016-0208.1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Lancing a finger elicits minimal pain in humans and is applied routinely to obtain small volumes of blood for clinical diagnostics. A modified lancet bleeding method and several blood sampling matrices were evaluated in this study for the purpose of routine elephant endotheliotropic herpesvirus (EEHV) surveillance in Asian elephants (Elephas maximus). The procedure enabled weekly sampling from elephants as young as 9 mo of age. The blood sampling matrices were evaluated for their sensitivity measuring β-actin, tumor necrosis factor α, and/or EEHV-1 by quantitative polymerase chain reaction assays. Foam and flocked swabs produced significantly (P < 0.05) lower quantitation cycles, ie, increased analytical sensitivity, than filter papers, Whatman® FTA cards, or conventional cotton-tipped swabs. The two swab types also demonstrated comparable analytical sensitivity to that of a similar volume of EDTA whole blood for the detection of EEHV-1 DNA. This lancet-and-swab technique proved satisfactory for the detection of EEHV-1 viremia in two Asian elephant calves, and in one instance viremia could be detected 5 days prior to the development of clinical signs. Low blood yield from the lancet application may reduce sensitivity and compromise early detection of viremia. Therefore, standard venipuncture remains the recommended blood sampling method, and training for consistent and regular vein access should continue to be the priority for collections holding elephants. However, if appropriate measures are taken to collect an optimum blood volume, this lancet-and-swab technique offers a suitable alternative for EEHV surveillance in situations where venipuncture may not be practical.
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24
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Abstract
Currently, 88 different Human Adenovirus (HAdV) types are grouped into seven HAdV species A to G. Most types (57) belong to species HAdV-D. Recombination between capsid genes (hexon, penton and fiber) is the main factor contributing to the diversity in species HAdV-D. Noteworthy, species HAdV-C contains so far only five types, although species HAdV-C is highly prevalent and clinically significant in immunosuppressed patients. Therefore, the evolution of species HAdV-C was studied by generating 51 complete genome sequences from circulating strains. Clustering of the whole genome HAdV-C sequences confirmed classical typing results (fifteen HAdV-C1, thirty HAdV-C2, four HAdV-C5, two HAdV-C6). However, two HAdV-C2 strains had a novel penton base sequence and thus were re-labeled as the novel type HAdV-C89. Fiber and early gene region 3 (E3) sequences clustered always with the corresponding prototype sequence but clustering of the E4 region indicated recombination events in 26 out of the 51 sequenced specimens. Recombination of the E1 gene region was detected in 16 circulating strains. As early gene region sequences are not considered in the type definition of HAdVs, evolution of HAdV-C remains on the subtype level. Nonetheless, recombination of the E1 and E4 gene regions may influence the virulence of HAdV-C strains.
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25
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Zachariah A, Sajesh PK, Santhosh S, Bathrachalam C, Megha M, Pandiyan J, Jishnu M, Kobragade RS, Long SY, Zong JC, Latimer EM, Heaggans SY, Hayward GS. Extended genotypic evaluation and comparison of twenty-two cases of lethal EEHV1 hemorrhagic disease in wild and captive Asian elephants in India. PLoS One 2018; 13:e0202438. [PMID: 30133540 PMCID: PMC6105008 DOI: 10.1371/journal.pone.0202438] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2018] [Accepted: 08/02/2018] [Indexed: 11/18/2022] Open
Abstract
Thirteen new lethal cases of acute hemorrhagic disease (HD) with typical histopathogical features were identified in young Asian elephants (Elephas maximus indicus) in India between 2013 and 2017. Eight occurred amongst free-ranging wild herds, with three more in camp-raised orphans and two in captive-born calves. All were confirmed to have high levels of Elephant Endotheliotropic Herpesvirus type 1A (EEHV1A) DNA detected within gross pathological lesions from necropsy tissue by multi-locus PCR DNA sequencing. The strains involved were all significantly different from one another and from nine previously described cases from Southern India (which included one example of EEHV1B). Overall, eight selected dispersed PCR loci totaling up to 6.1-kb in size were analyzed for most of the 22 cases, with extensive subtype clustering data being obtained at four hypervariable gene loci. In addition to the previously identified U48(gH-TK) and U51(vGPCR1) gene loci, these included two newly identified E5(vGPCR5) and E54(vOX2-1) loci mapping far outside of the classic EEHV1A versus EEHV1B subtype chimeric domains and towards the novel end segments of the genome that had not been evaluated previously. The high levels of genetic divergence and mosaic scrambling observed between adjacent loci match closely to the overall range of divergence found within 45 analyzed North American and European cases, but include some common relatively unique polymorphic features and preferred subtypes that appear to distinguish most but not all Indian strains from both those in Thailand and those outside range countries. Furthermore, more than half of the Indian cases studied here involved calves living within wild herds, whereas nearly all other cases identified in Asia so far represent rescued camp orphans or captive-born calves.
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Affiliation(s)
- A. Zachariah
- Department of Forests and Wildlife, Government of Kerala, Sultan Battery, Wayanad, India
| | - P. K. Sajesh
- SciGenom Research Foundation, Cheruthuruthy, Kerala, India
| | - S. Santhosh
- SciGenom Research Foundation, Cheruthuruthy, Kerala, India
| | | | - M. Megha
- SciGenom Research Foundation, Cheruthuruthy, Kerala, India
| | - J. Pandiyan
- AVC College, Mayiladuthurai, Tamilnadu, India
| | - M. Jishnu
- Department of Forests and Wildlife, Government of Kerala, Sultan Battery, Wayanad, India
| | - R. S. Kobragade
- Tadoba-Andhari Tiger Reserve, Chandrapur, Maharashtra, India
| | - S. Y. Long
- Viral Oncology Program, Department of Oncology, Johns Hopkins School of Medicine, Baltimore, MD, United States of America
| | - J-C Zong
- Viral Oncology Program, Department of Oncology, Johns Hopkins School of Medicine, Baltimore, MD, United States of America
| | - E. M. Latimer
- Wildlife Health Sciences, Smithsonian’s National Zoological Park, Washington, DC, United States of America
| | - S. Y. Heaggans
- Viral Oncology Program, Department of Oncology, Johns Hopkins School of Medicine, Baltimore, MD, United States of America
| | - G. S. Hayward
- Viral Oncology Program, Department of Oncology, Johns Hopkins School of Medicine, Baltimore, MD, United States of America
- * E-mail:
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26
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Kochakul V, Boonsri K, Tiwananthagorn S, Somgird C, Thitaram C, Pringproa K. Development of in situ hybridization for detection of elephant endotheliotropic herpesvirus in Asian elephants. J Vet Diagn Invest 2018; 30:628-632. [PMID: 29730973 DOI: 10.1177/1040638718773810] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Elephant endotheliotropic herpesvirus (EEHV) is one of the most important viral infectious diseases affecting the elephant population worldwide, especially juveniles and young adults. We developed a chromogenic in situ hybridization (ISH) test for detection of EEHV in Asian elephants ( Elephas maximus). Digoxigenin (DIG) DNA probes from the polymerase and terminase genes of EEHV were synthesized using a PCR DIG-labeling method, and detection of hybridized probe to target EEHV DNA was carried out by anti-DIG immunolabeling. Distribution of EEHV-1A and EEHV-4 genomes was found to be prominent in mononuclear phagocytic cells of spleen and endothelial cells of visceral organs. ISH enables the detection of EEHV infection and has applications in understanding pathogenesis of EEHV in Asian elephants.
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Affiliation(s)
- Varankpicha Kochakul
- Veterinary Diagnostic Laboratory (Kochakul, Boonsri), Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai, Thailand.,Department of Veterinary Biosciences and Veterinary Public Health (Tiwananthagorn, Pringproa), Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai, Thailand.,Department of Companion Animals and Wildlife Clinics (Somgird, Thitaram), Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai, Thailand.,Center of Excellence in Elephant Research and Education (Somgird, Thitaram, Pringproa), Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai, Thailand
| | - Kittikorn Boonsri
- Veterinary Diagnostic Laboratory (Kochakul, Boonsri), Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai, Thailand.,Department of Veterinary Biosciences and Veterinary Public Health (Tiwananthagorn, Pringproa), Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai, Thailand.,Department of Companion Animals and Wildlife Clinics (Somgird, Thitaram), Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai, Thailand.,Center of Excellence in Elephant Research and Education (Somgird, Thitaram, Pringproa), Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai, Thailand
| | - Saruda Tiwananthagorn
- Veterinary Diagnostic Laboratory (Kochakul, Boonsri), Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai, Thailand.,Department of Veterinary Biosciences and Veterinary Public Health (Tiwananthagorn, Pringproa), Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai, Thailand.,Department of Companion Animals and Wildlife Clinics (Somgird, Thitaram), Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai, Thailand.,Center of Excellence in Elephant Research and Education (Somgird, Thitaram, Pringproa), Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai, Thailand
| | - Chalermchart Somgird
- Veterinary Diagnostic Laboratory (Kochakul, Boonsri), Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai, Thailand.,Department of Veterinary Biosciences and Veterinary Public Health (Tiwananthagorn, Pringproa), Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai, Thailand.,Department of Companion Animals and Wildlife Clinics (Somgird, Thitaram), Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai, Thailand.,Center of Excellence in Elephant Research and Education (Somgird, Thitaram, Pringproa), Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai, Thailand
| | - Chatchote Thitaram
- Veterinary Diagnostic Laboratory (Kochakul, Boonsri), Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai, Thailand.,Department of Veterinary Biosciences and Veterinary Public Health (Tiwananthagorn, Pringproa), Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai, Thailand.,Department of Companion Animals and Wildlife Clinics (Somgird, Thitaram), Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai, Thailand.,Center of Excellence in Elephant Research and Education (Somgird, Thitaram, Pringproa), Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai, Thailand
| | - Kidsadagon Pringproa
- Veterinary Diagnostic Laboratory (Kochakul, Boonsri), Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai, Thailand.,Department of Veterinary Biosciences and Veterinary Public Health (Tiwananthagorn, Pringproa), Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai, Thailand.,Department of Companion Animals and Wildlife Clinics (Somgird, Thitaram), Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai, Thailand.,Center of Excellence in Elephant Research and Education (Somgird, Thitaram, Pringproa), Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai, Thailand
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27
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Production of antibody against elephant endotheliotropic herpesvirus (EEHV) unveils tissue tropisms and routes of viral transmission in EEHV-infected Asian elephants. Sci Rep 2018; 8:4675. [PMID: 29549315 PMCID: PMC5856810 DOI: 10.1038/s41598-018-22968-5] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2017] [Accepted: 03/05/2018] [Indexed: 01/06/2023] Open
Abstract
Elephant endotheliotropic herpesvirus (EEHV) is one of the most devastating viral infectious diseases in elephants worldwide. To date, it remains unclear how elephants get infected by the virus, where the virus persists, and what mechanisms drive the pathogenesis of the disease. The present study was aimed to develop an antibody against glycoprotein B (gB) of EEHV, investigate the EEHV tissue tropisms, and provide the possible routes of EEHV transmission in Asian elephants. Samples from elephant organs that had died from EEHV1A and EEHV4 infections, peripheral blood mononuclear cells (PBMC) from EEHV4- and non-EEHV-infected calves were used in this study. The results of western immunoblotting indicated that the antibody can be used for detection of gB antigens in both EEHV1A- and EEHV4-infected samples. Immunohistochemical detection indicated that the EEHV gB antigens were distributed mainly in the epithelial cells of the salivary glands, stomach and intestines. Immunofluorescence test of PBMC for EEHV gB in the EEHV4-infected calf indicated that the virus was observed predominantly in the mononuclear phagocytic cells. The findings in the present study unveil tissue tropisms in the EEHV1A- and EEHV4-infected calves and point out that saliva and intestinal content are likely sources for virus transmission in EEHV-infected Asian elephants.
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28
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Garvey M, Suárez NM, Kerr K, Hector R, Moloney-Quinn L, Arkins S, Davison AJ, Cullinane A. Equid herpesvirus 8: Complete genome sequence and association with abortion in mares. PLoS One 2018; 13:e0192301. [PMID: 29414990 PMCID: PMC5802896 DOI: 10.1371/journal.pone.0192301] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2017] [Accepted: 01/22/2018] [Indexed: 02/06/2023] Open
Abstract
Equid herpesvirus 8 (EHV-8), formerly known as asinine herpesvirus 3, is an alphaherpesvirus that is closely related to equid herpesviruses 1 and 9 (EHV-1 and EHV-9). The pathogenesis of EHV-8 is relatively little studied and to date has only been associated with respiratory disease in donkeys in Australia and horses in China. A single EHV-8 genome sequence has been generated for strain Wh in China, but is apparently incomplete and contains frameshifts in two genes. In this study, the complete genome sequences of four EHV-8 strains isolated in Ireland between 2003 and 2015 were determined by Illumina sequencing. Two of these strains were isolated from cases of abortion in horses, and were misdiagnosed initially as EHV-1, and two were isolated from donkeys, one with neurological disease. The four genome sequences are very similar to each other, exhibiting greater than 98.4% nucleotide identity, and their phylogenetic clustering together demonstrated that genomic diversity is not dependent on the host. Comparative genomic analysis revealed 24 of the 76 predicted protein sequences are completely conserved among the Irish EHV-8 strains. Evolutionary comparisons indicate that EHV-8 is phylogenetically closer to EHV-9 than it is to EHV-1. In summary, the first complete genome sequences of EHV-8 isolates from two host species over a twelve year period are reported. The current study suggests that EHV-8 can cause abortion in horses. The potential threat of EHV-8 to the horse industry and the possibility that donkeys may act as reservoirs of infection warrant further investigation.
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Affiliation(s)
- Marie Garvey
- Virology Unit, The Irish Equine Centre, Johnstown, Naas, County Kildare, Ireland
| | - Nicolás M. Suárez
- MRC-University of Glasgow Centre for Virus Research, Glasgow, United Kingdom
| | - Karen Kerr
- MRC-University of Glasgow Centre for Virus Research, Glasgow, United Kingdom
| | - Ralph Hector
- MRC-University of Glasgow Centre for Virus Research, Glasgow, United Kingdom
| | - Laura Moloney-Quinn
- Virology Unit, The Irish Equine Centre, Johnstown, Naas, County Kildare, Ireland
| | - Sean Arkins
- Department of Life Sciences, University of Limerick, Limerick, Ireland
| | - Andrew J. Davison
- MRC-University of Glasgow Centre for Virus Research, Glasgow, United Kingdom
- * E-mail: (AD); (AC)
| | - Ann Cullinane
- Virology Unit, The Irish Equine Centre, Johnstown, Naas, County Kildare, Ireland
- * E-mail: (AD); (AC)
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29
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Goldstein EJ, Harvey WT, Wilkie GS, Shepherd SJ, MacLean AR, Murcia PR, Gunson RN. Integrating patient and whole-genome sequencing data to provide insights into the epidemiology of seasonal influenza A(H3N2) viruses. Microb Genom 2017; 4. [PMID: 29310750 PMCID: PMC5857367 DOI: 10.1099/mgen.0.000137] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
Genetic surveillance of seasonal influenza is largely focused on sequencing of the haemagglutinin gene. Consequently, our understanding of the contribution of the remaining seven gene segments to the evolution and epidemiological dynamics of seasonal influenza is relatively limited. The increased availability of next-generation sequencing technologies allows rapid and economic whole-genome sequencing (WGS) of influenza virus. Here, 150 influenza A(H3N2) positive clinical specimens with linked epidemiological data, from the 2014/15 season in Scotland, were sequenced directly using both Sanger sequencing of the HA1 region and WGS using the Illumina MiSeq platform. Sequences generated by the two methods were highly correlated, and WGS provided on average >90 % whole genome coverage. As reported in other European countries during 2014/15, all strains belonged to genetic group 3C, with subgroup 3C.2a predominating. Multiple inter-subgroup reassortants were identified, including three 3C.3 viruses descended from a single reassortment event, which had persisted in the population. Cases of severe acute respiratory illness were significantly clustered on phylogenies of multiple gene segments indicating potential genetic factors warranting further investigation. Severe cases were also more likely to be associated with reassortant viruses and to occur later in the season. These results suggest that WGS provides an opportunity to develop our understanding of the relationship between the influenza genome and disease severity and the epidemiological consequences of within-subtype reassortment. Therefore, increased levels of WGS, linked to clinical and epidemiological data, could improve influenza surveillance.
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Affiliation(s)
- Emily J Goldstein
- 1West of Scotland Specialist Virology Centre, NHS Greater Glasgow and Clyde, Glasgow, UK
| | - William T Harvey
- 2Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, UK
| | - Gavin S Wilkie
- 3Medical Research Council-University of Glasgow Centre for Virus Research, Glasgow, UK
| | - Samantha J Shepherd
- 1West of Scotland Specialist Virology Centre, NHS Greater Glasgow and Clyde, Glasgow, UK
| | - Alasdair R MacLean
- 1West of Scotland Specialist Virology Centre, NHS Greater Glasgow and Clyde, Glasgow, UK
| | - Pablo R Murcia
- 3Medical Research Council-University of Glasgow Centre for Virus Research, Glasgow, UK
| | - Rory N Gunson
- 1West of Scotland Specialist Virology Centre, NHS Greater Glasgow and Clyde, Glasgow, UK
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30
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Suárez NM, Lau B, Kemble GM, Lee R, Mocarski ES, Wilkinson GWG, Adler SP, McVoy MA, Davison AJ. Genomic analysis of chimeric human cytomegalovirus vaccine candidates derived from strains Towne and Toledo. Virus Genes 2017; 53:650-655. [PMID: 28391502 PMCID: PMC5527331 DOI: 10.1007/s11262-017-1452-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2017] [Accepted: 03/30/2017] [Indexed: 12/11/2022]
Abstract
Human cytomegalovirus (HCMV) is an important opportunistic pathogen in immunocompromised patients and a major cause of congenital birth defects when acquired in utero. In the 1990s, four chimeric viruses were constructed by replacing genome segments of the high passage Towne strain with segments of the low passage Toledo strain, with the goal of obtaining live attenuated vaccine candidates that remained safe but were more immunogenic than the overly attenuated Towne vaccine. The chimeras were found to be safe when administered to HCMV-seronegative human volunteers, but to differ significantly in their ability to induce seroconversion. This suggests that chimera-specific genetic differences impacted the ability to replicate or persist in vivo and the consequent ability to induce an antibody response. To identify specific genomic breakpoints between Towne and Toledo sequences and establish whether spontaneous mutations or rearrangements had occurred during construction of the chimeras, complete genome sequences were determined. No major deletions or rearrangements were observed, although a number of unanticipated mutations were identified. However, no clear association emerged between the genetic content of the chimeras and the reported levels of vaccine-induced HCMV-specific humoral or cellular immune responses, suggesting that multiple genetic determinants are likely to impact immunogenicity. In addition to revealing the genome organization of the four vaccine candidates, this study provided an opportunity to probe the genetics of HCMV attenuation in humans. The results may be valuable in the future design of safe live or replication-defective vaccines that optimize immunogenicity and efficacy.
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Affiliation(s)
- Nicolás M Suárez
- MRC-University of Glasgow Centre for Virus Research, Glasgow, UK
| | - Betty Lau
- MRC-University of Glasgow Centre for Virus Research, Glasgow, UK
| | | | - Ronzo Lee
- Department of Pediatrics, Virginia Commonwealth University, Richmond, VA, USA
| | - Edward S Mocarski
- Department of Microbiology and Immunology, Emory Vaccine Center, Emory University, Atlanta, GA, USA
| | - Gavin W G Wilkinson
- Division of Infection and Immunity, School of Medicine, Cardiff University, Cardiff, UK
| | - Stuart P Adler
- CMV Research Foundation, Virginia Commonwealth University, Richmond, VA, USA
| | - Michael A McVoy
- Department of Pediatrics, Virginia Commonwealth University, Richmond, VA, USA.
| | - Andrew J Davison
- MRC-University of Glasgow Centre for Virus Research, Glasgow, UK
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31
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Long SY, Latimer EM, Hayward GS. Review of Elephant Endotheliotropic Herpesviruses and Acute Hemorrhagic Disease. ILAR J 2016; 56:283-96. [PMID: 26912715 DOI: 10.1093/ilar/ilv041] [Citation(s) in RCA: 93] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
More than 100 young captive and wild Asian elephants are known to have died from a rapid-onset, acute hemorrhagic disease caused primarily by multiple distinct strains of two closely related chimeric variants of a novel herpesvirus species designated elephant endotheliotropic herpesvirus (EEHV1A and EEHV1B). These and two other species of Probosciviruses (EEHV4 and EEHV5) are evidently ancient and likely nearly ubiquitous asymptomatic infections of adult Asian elephants worldwide that are occasionally shed in trunk wash secretions. Although only a handful of similar cases have been observed in African elephants, they also have proved to harbor their own multiple and distinct species of Probosciviruses-EEHV2, EEHV3, EEHV6, and EEHV7-found in lung and skin nodules or saliva. For reasons that are not yet understood, approximately 20% of Asian elephant calves appear to be susceptible to the disease when primary infections are not controlled by normal innate cellular and humoral immune responses. Sensitive specific polymerase chain reaction (PCR) DNA blood tests have been developed, routine monitoring has been established, the complete large DNA genomes of each of the four Asian EEHV species have now been sequenced, and PCR gene subtyping has provided unambiguous evidence that this is a sporadic rather than epidemic disease that it is not being spread among zoos or other elephant housing facilities. Nevertheless, researchers have not yet been able to propagate EEHV in cell culture, determine whether or not human antiherpesvirus drugs are effective inhibitors, or develop serology assays that can distinguish between antibodies against the multiple different EEHV species.
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Affiliation(s)
- Simon Y Long
- Simon Y. Long, MS, VMD, is a pathology postdoctoral fellow in the Department of Molecular and Comparative Pathobiology and a graduate student under Dr. Gary S. Hayward in the graduate program in Cellular and Molecular Medicine at Johns Hopkins School of Medicine in Baltimore, Maryland. Erin M. Latimer, MS, is a research specialist and manager of the National Elephant Herpesvirus Laboratory at the Smithsonian's National Zoological Park in Washington, DC. Gary S. Hayward, PhD, is a professor in the Viral Oncology Program, Pharmacology and Molecular Sciences, and Pathology Departments at Johns Hopkins School of Medicine in Baltimore, Maryland
| | - Erin M Latimer
- Simon Y. Long, MS, VMD, is a pathology postdoctoral fellow in the Department of Molecular and Comparative Pathobiology and a graduate student under Dr. Gary S. Hayward in the graduate program in Cellular and Molecular Medicine at Johns Hopkins School of Medicine in Baltimore, Maryland. Erin M. Latimer, MS, is a research specialist and manager of the National Elephant Herpesvirus Laboratory at the Smithsonian's National Zoological Park in Washington, DC. Gary S. Hayward, PhD, is a professor in the Viral Oncology Program, Pharmacology and Molecular Sciences, and Pathology Departments at Johns Hopkins School of Medicine in Baltimore, Maryland
| | - Gary S Hayward
- Simon Y. Long, MS, VMD, is a pathology postdoctoral fellow in the Department of Molecular and Comparative Pathobiology and a graduate student under Dr. Gary S. Hayward in the graduate program in Cellular and Molecular Medicine at Johns Hopkins School of Medicine in Baltimore, Maryland. Erin M. Latimer, MS, is a research specialist and manager of the National Elephant Herpesvirus Laboratory at the Smithsonian's National Zoological Park in Washington, DC. Gary S. Hayward, PhD, is a professor in the Viral Oncology Program, Pharmacology and Molecular Sciences, and Pathology Departments at Johns Hopkins School of Medicine in Baltimore, Maryland
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32
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Myster F, van Beurden SJ, Sorel O, Suárez NM, Vanderplasschen A, Davison AJ, Dewals BG. Genomic duplication and translocation of reactivation transactivator and bZIP-homolog genes is a conserved event in alcelaphine herpesvirus 1. Sci Rep 2016; 6:38607. [PMID: 27924936 PMCID: PMC5141506 DOI: 10.1038/srep38607] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2016] [Accepted: 11/09/2016] [Indexed: 12/25/2022] Open
Abstract
Alcelaphine herpesvirus 1 (AlHV-1) is a gammaherpesvirus carried asymptomatically by wildebeest. Upon cross-species transmission, AlHV-1 induces malignant catarrhal fever (MCF), a fatal lymphoproliferative disease of ruminants, including cattle. The strain C500 has been cloned as an infectious, pathogenic bacterial artificial chromosome (BAC) that is used to study MCF. Although AlHV-1 infection can be established in cell culture, multiple passages in vitro cause a loss of virulence associated with rearrangements of the viral genome. Here, sequencing of the BAC clone showed that the long unique region (LUR) of the genome is nearly identical to that of the previously sequenced strain from which the BAC was derived, and identified the duplication and translocation of a region from within LUR, containing the entire coding sequences of ORF50-encoding reactivation transactivator Rta and A6-encoding bZIP protein genes. The duplicated region was further located to a position within the terminal repeat (TR) and its deletion resulted in lower ORF50 expression levels and reduced viral fitness. Finally, the presence of a similar but not identical duplication and translocation containing both genes was found in AlHV-1 strain WC11. These results indicate that selection pressure for enhanced viral fitness may drive the duplication of ORF50 and A6 in AlHV-1.
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Affiliation(s)
- Françoise Myster
- Fundamental and Applied Research in Animals and Health (FARAH), Immunology-Vaccinology, Faculty of Veterinary Medicine (B43b), University of Liège, Belgium
| | - Steven J van Beurden
- Fundamental and Applied Research in Animals and Health (FARAH), Immunology-Vaccinology, Faculty of Veterinary Medicine (B43b), University of Liège, Belgium
| | - Océane Sorel
- Fundamental and Applied Research in Animals and Health (FARAH), Immunology-Vaccinology, Faculty of Veterinary Medicine (B43b), University of Liège, Belgium
| | - Nicolás M Suárez
- MRC - University of Glasgow Centre for Virus Research, Sir Michael Stoker Building, Glasgow G61 1QH, UK
| | - Alain Vanderplasschen
- Fundamental and Applied Research in Animals and Health (FARAH), Immunology-Vaccinology, Faculty of Veterinary Medicine (B43b), University of Liège, Belgium
| | - Andrew J Davison
- MRC - University of Glasgow Centre for Virus Research, Sir Michael Stoker Building, Glasgow G61 1QH, UK
| | - Benjamin G Dewals
- Fundamental and Applied Research in Animals and Health (FARAH), Immunology-Vaccinology, Faculty of Veterinary Medicine (B43b), University of Liège, Belgium
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Dastjerdi A, Seilern-Moy K, Darpel K, Steinbach F, Molenaar F. Surviving and fatal Elephant Endotheliotropic Herpesvirus-1A infections in juvenile Asian elephants - lessons learned and recommendations on anti-herpesviral therapy. BMC Vet Res 2016; 12:178. [PMID: 27567895 PMCID: PMC5002104 DOI: 10.1186/s12917-016-0806-5] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2016] [Accepted: 08/18/2016] [Indexed: 11/10/2022] Open
Abstract
Background Elephant Endotheliotropic Herpesviruses (EEHVs) can cause acute haemorrhagic disease in young Asian elephants (Elephas maximus) and clinical EEHV infections account for the majority of their fatalities. The anti-herpesviral drug famciclovir (FCV) has been used routinely to treat viraemic at-risk elephants, but thus far without proven efficacy. This paper presents clinical and virological investigations of two EEHV-1A infected elephants treated with FCV, and discusses anti-herpesvirus therapies of viraemic elephants. Cases presentations Two 1.5 year old male Asian elephants at a zoological collection in the UK developed clinical EEHV-1A infections. Case 1 showed signs of myalgia for the duration of 24 hours before returning back to normal. EEHV-1A DNAemia was confirmed on the day of clinical signs and continued to be present for 18 days in total. Trunk shedding of the virus commenced 10 days after detection of initial DNAemia. Case 2 tested positive for EEHV-1A DNAemia in a routine blood screening sample in the absence of clinical signs. The blood viral load increased exponentially leading up to fatal clinical disease seven days after initial detection of DNAemia. Both calves were treated with 15 mg/kg FCV per rectum on detection of DNAemia and penciclovir, the FCV metabolite, could be detected in the blood at assumed therapeutic levels. The early indicators for clinical disease were a marked absolute and relative drop in white blood cells, particularly monocytes prior to the detection of viraemia. The most prognostic haematological parameter at later stages of the disease was the platelet count showing a continuous sharp decline throughout, followed by a dramatic drop at the time of death. Conclusions The EEHV-1A viraemic animals investigated here further highlight the ongoing threat posed by these viruses to juvenile Asian elephants. The findings call into question the efficacy of rectal FCV in clinical cases and direct towards the use of alternative anti-herpesvirus drugs and complementary treatments such as plasma infusions if no improvement in either viral load or the above-mentioned blood parameters are observed in the initial days of viraemia despite anti-herpesvirus therapy.
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Affiliation(s)
- Akbar Dastjerdi
- Animal and Plant Health Agency-Weybridge, New Haw, Addlestone, Surrey, KT15 3NB, UK.
| | - Katharina Seilern-Moy
- Animal and Plant Health Agency-Weybridge, New Haw, Addlestone, Surrey, KT15 3NB, UK.,School of Veterinary Medicine, Faculty of Health and Medical Sciences, University of Surrey, Guildford, GU2 7XH, UK
| | - Karin Darpel
- School of Veterinary Medicine, Faculty of Health and Medical Sciences, University of Surrey, Guildford, GU2 7XH, UK
| | - Falko Steinbach
- Animal and Plant Health Agency-Weybridge, New Haw, Addlestone, Surrey, KT15 3NB, UK.,School of Veterinary Medicine, Faculty of Health and Medical Sciences, University of Surrey, Guildford, GU2 7XH, UK
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Molecular characterisation and genetic variation of Elephant Endotheliotropic Herpesvirus infection in captive young Asian elephants in Thailand. INFECTION GENETICS AND EVOLUTION 2016; 44:487-494. [PMID: 27503594 DOI: 10.1016/j.meegid.2016.08.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Revised: 08/01/2016] [Accepted: 08/03/2016] [Indexed: 11/21/2022]
Abstract
Elephant Endotheliotropic Herpesvirus (EEHV) is emerging as a new threat for elephant conservation, since being identified as the cause of severe, often fatal, haemorrhagic disease in young Asian elephants. To describe positive cases and the molecular relatedness of virus detected in elephants in Thailand, we re-examined all available of EEHV samples occurring in young elephants in Thailand between 2006 and 2014 (n=24). Results indicated 75% (18/24) of suspected cases were positive for EEHV by semi-nested PCR. Further gene analysis identified these positive cases as EEHV1A (72%, 13/18 cases), EEHV1B (11%, 2/18) and EEHV4 (17%, 3/18). This study is the first to phylogenetically analyse and provide an overview of most of the known EEHV cases that have occurred in Thailand. Positive individuals ranged in age from one to nine years, with no sex association detected, and occurred across geographical locations throughout the country. All individuals, except one, were captive-born. No history of direct contact among the cases was recorded, and this together with the fact that various subtype clusters of virus were found, implied that none of the positive cases were epidemiologically related. These results concur with the hypothesis that EEHV1 is likely to be an ancient endogenous pathogen in Asian elephants. It is recommended that active surveillance and routine monitoring for EEHV should be undertaken in all elephant range countries, to gain a better understanding of the epidemiology, transmission and prevention of this disease.
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Complete Genome Sequence of Elephant Endotheliotropic Herpesvirus 4, the First Example of a GC-Rich Branch Proboscivirus. mSphere 2016; 1:mSphere00081-15. [PMID: 27340695 PMCID: PMC4911795 DOI: 10.1128/msphere.00081-15] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2016] [Accepted: 05/09/2016] [Indexed: 01/25/2023] Open
Abstract
A novel group of mammalian DNA viruses called elephant endotheliotropic herpesviruses (EEHVs) belonging to the Proboscivirus genus has been associated with nearly 100 cases of highly lethal acute hemorrhagic disease in young Asian elephants worldwide. The complete 180-kb genomes of prototype strains from three AT-rich branch viruses, EEHV1A, EEHV1B, and EEHV5, have been published. However, less than 6 kb of DNA sequence each from EEHV3, EEHV4, and EEHV7 showed them to be a hugely diverged second major branch with GC-rich characteristics. Here, we determined the complete 206-kb genome of EEHV4(Baylor) directly from trunk wash DNA by next-generation sequencing and de novo assembly procedures. Among a total of 119 genes with an overall colinear organization similar to those of the AT-rich EEHVs, major features of EEHV4 include a family of 26 paralogous 7xTM and vGPCR-like genes plus 25 novel or missing genes. The genome also contains an unusual distribution of tracts of 5 to 11 successive A or T nucleotides in intergenic domains between the mostly much higher GC content protein coding regions. Furthermore, an extremely high GC-rich bias in the third wobble position of codons clearly delineates the coding regions for many but not all proteins. There are also two novel captured cellular genes, including a C-type lectin (vECTL) and an O-linked acetylglucosamine transferase (vOGT), as well as an unusually large and complex Ori-Lyt dyad symmetry domain. Finally, 30 kb from a second strain proved to include three small chimeric domains, indicating the existence of distinct EEHV4A and EEHV4B subtypes. IMPORTANCE Multiple species of herpesviruses from three different lineages of the Proboscivirus genus (EEHV1/6, EEHV2/5, and EEHV3/4/7) infect both Asian and African elephants, but lethal hemorrhagic disease is largely confined to Asian elephant calves and is predominantly associated with EEHV1. Milder disease caused by EEHV5 or EEHV4 is being increasingly recognized as well, but little is known about the latter, which is estimated to have diverged at least 35 million years ago from the others within a distinctive GC-rich branch of the Proboscivirus genus. Here, we have determined the complete genomic DNA sequence of a strain of EEHV4 obtained from a trunk wash sample collected from a surviving Asian elephant calf undergoing asymptomatic shedding during convalescence after an acute hemorrhagic disease episode. This represents the first example from among the three known GC-rich branch Proboscivirus species to be assembled and fully annotated. Several distinctive features of EEHV4 compared to AT-rich branch genomes are described.
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Comparison of the Gene Coding Contents and Other Unusual Features of the GC-Rich and AT-Rich Branch Probosciviruses. mSphere 2016; 1:mSphere00091-16. [PMID: 27340696 PMCID: PMC4911796 DOI: 10.1128/msphere.00091-16] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2016] [Accepted: 05/09/2016] [Indexed: 11/29/2022] Open
Abstract
Multiple species of herpesviruses from three different lineages of the Proboscivirus genus (EEHV1/6, EEHV2/5, and EEHV3/4/7) infect either Asian or African elephants, but the highly lethal hemorrhagic disease is largely confined to Asian elephant calves and is predominantly associated with EEHV1. In the accompanying paper [P. D. Ling et al., mSphere 1(3):e00081-15, http://dx.doi.org/10.1128/mSphere.00081-15], we report the complete 206-kb genome of EEHV4, the third different species causing disease in Asian elephants and the first example of a GC-rich branch proboscivirus. To gain insights into the nature and differential properties of these two very anciently diverged lineages of elephant herpesviruses, we describe here several additional unusual features found in the complete GC-rich genome of EEHV4 with particular emphasis on patterns of divergence as well as common unique features that are distinct from those of all other herpesviruses, such as the enlarged AT-rich intergenic domains and gene families, including the large number of vGPCR-like proteins. Nearly 100 cases of lethal acute hemorrhagic disease in young Asian elephants have been reported worldwide. All tested cases contained high levels of elephant endotheliotropic herpesvirus (EEHV) DNA in pathological blood or tissue samples. Seven known major types of EEHVs have been partially characterized and shown to all belong to the novel Proboscivirus genus. However, the recently determined 206-kb EEHV4 genome proved to represent the prototype of a GC-rich branch virus that is very distinct from the previously published 180-kb EEHV1A, EEHV1B, and EEHV5A genomes, which all fall within an alternative AT-rich branch. Although EEHV4 retains the large family of 7xTM and vGPCR-like genes, six are unique to either just one or the other branch. While both branches display a highly enriched distribution of A and T tracts in intergenic domains, they are generally much larger within the GC-rich branch. Both branches retain the vGCNT1 acetylglucosamine transferase and at least one vOX-2 gene, but the two branches differ by 25 genes overall, with the AT-rich branch encoding a fucosyl transferase (vFUT9) plus two or three more vOX2 proteins and an immunoglobulin-like gene family that are all absent from the GC-rich branch. Several envelope glycoproteins retain only 15 to 20% protein identity or less across the two branches. Finally, the two plausible predicted transcriptional regulatory proteins display no homology at all to those in the alpha-, beta-, or gammaherpesvirus subfamilies. These results reinforce our previous proposal that the probosciviruses should be designated a new subfamily of mammalian herpesviruses. IMPORTANCE Multiple species of herpesviruses from three different lineages of the Proboscivirus genus (EEHV1/6, EEHV2/5, and EEHV3/4/7) infect either Asian or African elephants, but the highly lethal hemorrhagic disease is largely confined to Asian elephant calves and is predominantly associated with EEHV1. In the accompanying paper [P. D. Ling et al., mSphere 1(3):e00081-15, 10.1128/mSphere.00081-15], we report the complete 206-kb genome of EEHV4, the third different species causing disease in Asian elephants and the first example of a GC-rich branch proboscivirus. To gain insights into the nature and differential properties of these two very anciently diverged lineages of elephant herpesviruses, we describe here several additional unusual features found in the complete GC-rich genome of EEHV4 with particular emphasis on patterns of divergence as well as common unique features that are distinct from those of all other herpesviruses, such as the enlarged AT-rich intergenic domains and gene families, including the large number of vGPCR-like proteins.
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Papageorgiou KV, Suárez NM, Wilkie GS, McDonald M, Graham EM, Davison AJ. Genome Sequence of Canine Herpesvirus. PLoS One 2016; 11:e0156015. [PMID: 27213534 PMCID: PMC4877106 DOI: 10.1371/journal.pone.0156015] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2015] [Accepted: 05/09/2016] [Indexed: 11/18/2022] Open
Abstract
Canine herpesvirus is a widespread alphaherpesvirus that causes a fatal haemorrhagic disease of neonatal puppies. We have used high-throughput methods to determine the genome sequences of three viral strains (0194, V777 and V1154) isolated in the United Kingdom between 1985 and 2000. The sequences are very closely related to each other. The canine herpesvirus genome is estimated to be 125 kbp in size and consists of a unique long sequence (97.5 kbp) and a unique short sequence (7.7 kbp) that are each flanked by terminal and internal inverted repeats (38 bp and 10.0 kbp, respectively). The overall nucleotide composition is 31.6% G+C, which is the lowest among the completely sequenced alphaherpesviruses. The genome contains 76 open reading frames predicted to encode functional proteins, all of which have counterparts in other alphaherpesviruses. The availability of the sequences will facilitate future research on the diagnosis and treatment of canine herpesvirus-associated disease.
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Affiliation(s)
- Konstantinos V. Papageorgiou
- MRC–University of Glasgow Centre for Virus Research, Glasgow, United Kingdom
- Department of Microbiology and Infectious Diseases, Veterinary Faculty, School of Health Sciences, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Nicolás M. Suárez
- MRC–University of Glasgow Centre for Virus Research, Glasgow, United Kingdom
| | - Gavin S. Wilkie
- MRC–University of Glasgow Centre for Virus Research, Glasgow, United Kingdom
| | - Michael McDonald
- Division of Veterinary Pathology, Public Health and Disease Surveillance, University of Glasgow, Glasgow, United Kingdom
| | - Elizabeth M. Graham
- Division of Veterinary Pathology, Public Health and Disease Surveillance, University of Glasgow, Glasgow, United Kingdom
| | - Andrew J. Davison
- MRC–University of Glasgow Centre for Virus Research, Glasgow, United Kingdom
- * E-mail:
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Fatal elephant endotheliotropic herpesvirus-1 and -4 co-infection in a juvenile Asian elephant in Europe. JMM Case Rep 2016. [DOI: 10.1099/jmmcr.0.005005] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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Seilern-Moy K, Darpel K, Steinbach F, Dastjerdi A. Distribution and load of elephant endotheliotropic herpesviruses in tissues from associated fatalities of Asian elephants. Virus Res 2016; 220:91-6. [PMID: 27102836 DOI: 10.1016/j.virusres.2016.04.012] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2016] [Accepted: 04/14/2016] [Indexed: 11/15/2022]
Abstract
Elephant Endotheliotropic Herpesviruses (EEHVs) are the cause of a highly fatal haemorrhagic disease in elephants primarily affecting young Asian elephants (Elephas maximus) in both captivity and in the wild. The viruses have emerged as a significant threat to Asian elephant conservation, critically affecting overall sustainability of their population. So far insight into the pathogenesis of EEHV infections has been restricted to examination of EEHV-infected tissues. However, little is known about distribution and burden of the viruses within the organs of fatal cases, crucial elements in the understanding of the virus pathogenesis. This study was therefore undertaken to assess the extent of organ and cell involvement in fatal cases of EEHV-1A, 1B and 5 using a quantitative real-time PCR. EEHV-1 and 5 DNA were detectable in all the tissues examined, albeit with substantial differences in the viral DNA load. The highest EEHV-1A DNA load was observed in the liver, followed by the heart, thymus and tongue. EEHV-1B and 5 showed the highest DNA load in the heart, followed by tongue and liver. This study provides new insights into EEHV pathogenicity and has implications in choice of sample type for disease investigation and virus isolation.
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Affiliation(s)
- Katharina Seilern-Moy
- Animal and Plant Health Agency-Weybridge, New Haw, Addlestone, Surrey KT15 3NB, UK; Division of Microbial Sciences, Faculty of Health and Medical Sciences, University of Surrey, Guildford, Surrey GU2 7XH, UK
| | - Karin Darpel
- Division of Microbial Sciences, Faculty of Health and Medical Sciences, University of Surrey, Guildford, Surrey GU2 7XH, UK
| | - Falko Steinbach
- Animal and Plant Health Agency-Weybridge, New Haw, Addlestone, Surrey KT15 3NB, UK
| | - Akbar Dastjerdi
- Animal and Plant Health Agency-Weybridge, New Haw, Addlestone, Surrey KT15 3NB, UK.
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Genome Sequences of Two Pseudorabies Virus Strains Isolated in Greece. GENOME ANNOUNCEMENTS 2016; 4:4/1/e01624-15. [PMID: 26798112 PMCID: PMC4722279 DOI: 10.1128/genomea.01624-15] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Pseudorabies virus (species Suid herpesvirus 1) belongs to the genus Varicellovirus, subfamily Alphaherpesvirinae, family Herpesviridae, and is the causative agent of an acute and frequently fatal disease that affects mainly pigs. Here, we report the genome sequences of two strains of this virus isolated in Greece in 2010.
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Detection of Quiescent Infections with Multiple Elephant Endotheliotropic Herpesviruses (EEHVs), Including EEHV2, EEHV3, EEHV6, and EEHV7, within Lymphoid Lung Nodules or Lung and Spleen Tissue Samples from Five Asymptomatic Adult African Elephants. J Virol 2015; 90:3028-43. [PMID: 26719245 DOI: 10.1128/jvi.02936-15] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2015] [Accepted: 12/23/2015] [Indexed: 11/20/2022] Open
Abstract
UNLABELLED More than 80 cases of lethal hemorrhagic disease associated with elephant endotheliotropic herpesviruses (EEHVs) have been identified in young Asian elephants worldwide. Diagnostic PCR tests detected six types of EEHV in blood of elephants with acute disease, although EEHV1A is the predominant pathogenic type. Previously, the presence of herpesvirus virions within benign lung and skin nodules from healthy African elephants led to suggestions that African elephants may be the source of EEHV disease in Asian elephants. Here, we used direct PCR-based DNA sequencing to detect EEHV genomes in necropsy tissue from five healthy adult African elephants. Two large lung nodules collected from culled wild South African elephants contained high levels of either EEHV3 alone or both EEHV2 and EEHV3. Similarly, a euthanized U.S. elephant proved to harbor multiple EEHV types distributed nonuniformly across four small lung nodules, including high levels of EEHV6, lower levels of EEHV3 and EEHV2, and a new GC-rich branch type, EEHV7. Several of the same EEHV types were also detected in random lung and spleen samples from two other elephants. Sanger PCR DNA sequence data comprising 100 kb were obtained from a total of 15 different strains identified, with (except for a few hypervariable genes) the EEHV2, EEHV3, and EEHV6 strains all being closely related to known genotypes from cases of acute disease, whereas the seven loci (4.0 kb) obtained from EEHV7 averaged 18% divergence from their nearest relative, EEHV3. Overall, we conclude that these four EEHV species, but probably not EEHV1, occur commonly as quiescent infections in African elephants. IMPORTANCE Acute hemorrhagic disease characterized by high-level viremia due to infection by members of the Proboscivirus genus threatens the future breeding success of endangered Asian elephants worldwide. Although the genomes of six EEHV types from acute cases have been partially or fully characterized, lethal disease predominantly involves a variety of strains of EEHV1, whose natural host has been unclear. Here, we carried out genotype analyses by partial PCR sequencing of necropsy tissue from five asymptomatic African elephants and identified multiple simultaneous infections by several different EEHV types, including high concentrations in lymphoid lung nodules. Overall, the results provide strong evidence that EEHV2, EEHV3, EEHV6, and EEHV7 represent natural ubiquitous infections in African elephants, whereas Asian elephants harbor EEHV1A, EEHV1B, EEHV4, and EEHV5. Although a single case of fatal cross-species infection by EEHV3 is known, the results do not support the previous concept that highly pathogenic EEHV1A crossed from African to Asian elephants in zoos.
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Kamperschroer C, Gosink MM, Kumpf SW, O'Donnell LM, Tartaro KR. The genomic sequence of lymphocryptovirus from cynomolgus macaque. Virology 2015; 488:28-36. [PMID: 26590795 DOI: 10.1016/j.virol.2015.10.025] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2014] [Revised: 11/27/2014] [Accepted: 10/27/2015] [Indexed: 12/12/2022]
Abstract
Lymphocryptoviruses such as Epstein-Barr virus (EBV) cause persistent infections in human and non-human primates, and suppression of the immune system can increase the risk of lymphocryptovirus (LCV)-associated tumor development in both human and non-human primates. To enable LCV infection as a non-clinical model to study effects of therapeutics on EBV immunity, we determined the genomic DNA sequence of the LCV from cynomolgus macaque, a species commonly used for non-clinical testing. Comparison to rhesus macaque LCV and human EBV sequences indicates that LCV from the cynomolgus macaque has the same genomic arrangement and a high degree of similarity in most genes, especially with rhesus macaque LCV. Genes showing lower similarity were those encoding proteins involved in latency and/or tumor promotion or immune evasion. The genomic sequence of LCV from cynomolgus macaque should aid the development of non-clinical tools for identifying therapeutics that impact LCV immunity and carry potential lymphoma risk.
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Affiliation(s)
- Cris Kamperschroer
- Drug Safety Research and Development, Pfizer Global Research and Development, Pfizer, Inc., Groton, CT, USA.
| | - Mark M Gosink
- Drug Safety Research and Development, Pfizer Global Research and Development, Pfizer, Inc., Groton, CT, USA
| | - Steven W Kumpf
- Drug Safety Research and Development, Pfizer Global Research and Development, Pfizer, Inc., Groton, CT, USA
| | - Lynn M O'Donnell
- Drug Safety Research and Development, Pfizer Global Research and Development, Pfizer, Inc., Groton, CT, USA
| | - Karrie R Tartaro
- Drug Safety Research and Development, Pfizer Global Research and Development, Pfizer, Inc., Groton, CT, USA
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Houldcroft CJ, Breuer J. Tales from the crypt and coral reef: the successes and challenges of identifying new herpesviruses using metagenomics. Front Microbiol 2015; 6:188. [PMID: 25821447 PMCID: PMC4358218 DOI: 10.3389/fmicb.2015.00188] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2014] [Accepted: 02/20/2015] [Indexed: 12/14/2022] Open
Abstract
Herpesviruses are ubiquitous double-stranded DNA viruses infecting many animals, with the capacity to cause disease in both immunocompetent and immunocompromised hosts. Different herpesviruses have different cell tropisms, and have been detected in a diverse range of tissues and sample types. Metagenomics—encompassing viromics—analyses the nucleic acid of a tissue or other sample in an unbiased manner, making few or no prior assumptions about which viruses may be present in a sample. This approach has successfully discovered a number of novel herpesviruses. Furthermore, metagenomic analysis can identify herpesviruses with high degrees of sequence divergence from known herpesviruses and does not rely upon culturing large quantities of viral material. Metagenomics has had success in two areas of herpesvirus sequencing: firstly, the discovery of novel exogenous and endogenous herpesviruses in primates, bats and cnidarians; and secondly, in characterizing large areas of the genomes of herpesviruses previously only known from small fragments, revealing unexpected diversity. This review will discuss the successes and challenges of using metagenomics to identify novel herpesviruses, and future directions within the field.
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Affiliation(s)
- Charlotte J Houldcroft
- Infection, Inflammation and Rheumatology, Institute of Child Health, University College London , London, UK
| | - Judith Breuer
- Infection, Inflammation and Rheumatology, Institute of Child Health, University College London , London, UK ; Division of Infection and Immunity, University College London , London, UK
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