1
|
Degeling C, Gilbert GL, Annand E, Taylor M, Walsh MG, Ward MP, Wilson A, Johnson J. Managing the risk of Hendra virus spillover in Australia using ecological approaches: A report on three community juries. PLoS One 2018; 13:e0209798. [PMID: 30596719 PMCID: PMC6312203 DOI: 10.1371/journal.pone.0209798] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Accepted: 12/11/2018] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Hendra virus (HeV) infection is endemic in Australian flying-fox populations. Habitat loss has increased the peri-urban presence of flying-foxes, increasing the risk of contact and therefore viral 'spillovers' into horse and human populations. An equine vaccine is available and horse-husbandry practices that minimize HeV exposure are encouraged, but their adoption is suboptimal. Ecological approaches-such as habitat creation and conservation-could complement vaccination and behavioural strategies by reducing spillover risks, but these are controversial. METHODS We convened three community juries (two regional; one metropolitan) to elicit the views of well-informed citizens on the acceptability of adding ecological approaches to current interventions for HeV risk. Thirty-one participants of diverse backgrounds, mixed genders and ages were recruited using random-digit-dialling. Each jury was presented with balanced factual evidence, given time to ask questions of expert presenters and, after deliberation, come to well-reasoned conclusions. RESULTS All juries voted unanimously that ecological strategies should be included in HeV risk management strategies but concluded that current interventions-including vaccination and changing horse-husbandry practices-must remain the priority. The key reasons given for adopting ecological approaches were: (i) they address underlying drivers of disease emergence, (ii) the potential to prevent spillover of other bat-borne pathogens, and (iii) there would be broader community benefits. Juries differed regarding the best mechanism to create/conserve flying-fox habitat: participants in regional centres favoured direct government action, whereas the metropolitan jury preferred to place the burden on landholders. CONCLUSIONS Informed citizens acknowledge the value of addressing the drivers of bat-borne infectious risks but differ substantially as to the best implementation strategies. Ecological approaches to securing bat habitat could find broad social support in Australia, but disagreement about how best to achieve them indicates the need for negotiation with affected communities to co-develop fair, effective and locally appropriate policies.
Collapse
Affiliation(s)
- Chris Degeling
- Australian Centre for Health Engagement Evidence and Values, School of Health and Society, University of Wollongong, Wollongong, NSW, Australia
- * E-mail:
| | - Gwendolyn L. Gilbert
- Sydney Health Ethics, School of Public Health, University of Sydney, Sydney, NSW, Australia
- Marie Bashir Institute for Infectious Disease and Biosecurity, University of Sydney, Sydney, NSW, Australia
| | - Edward Annand
- Marie Bashir Institute for Infectious Disease and Biosecurity, University of Sydney, Sydney, NSW, Australia
- Sydney School of Veterinary Science, University of Sydney, Camden, NSW, Australia
- EquiEpiVet, Picton, NSW, Australia
| | - Melanie Taylor
- Department of Psychology, Macquarie University, Sydney, NSW, Australia
| | - Michael G. Walsh
- Marie Bashir Institute for Infectious Disease and Biosecurity, University of Sydney, Sydney, NSW, Australia
- Westmead Clinical School, Sydney Medical School, University of Sydney, Westmead, NSW, Australia
| | - Michael P. Ward
- Sydney School of Veterinary Science, University of Sydney, Camden, NSW, Australia
| | - Andrew Wilson
- Menzies Centre for Health Policy, University of Sydney, Sydney, NSW, Australia
| | - Jane Johnson
- Sydney Health Ethics, School of Public Health, University of Sydney, Sydney, NSW, Australia
- Marie Bashir Institute for Infectious Disease and Biosecurity, University of Sydney, Sydney, NSW, Australia
- Westmead Clinical School, Sydney Medical School, University of Sydney, Westmead, NSW, Australia
| |
Collapse
|
2
|
Leon AJ, Borisevich V, Boroumand N, Seymour R, Nusbaum R, Escaffre O, Xu L, Kelvin DJ, Rockx B. Host gene expression profiles in ferrets infected with genetically distinct henipavirus strains. PLoS Negl Trop Dis 2018; 12:e0006343. [PMID: 29538374 PMCID: PMC5868854 DOI: 10.1371/journal.pntd.0006343] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2017] [Revised: 03/26/2018] [Accepted: 02/24/2018] [Indexed: 02/05/2023] Open
Abstract
Henipavirus infection causes severe respiratory and neurological disease in humans that can be fatal. To characterize the pathogenic mechanisms of henipavirus infection in vivo, we performed experimental infections in ferrets followed by genome-wide gene expression analysis of lung and brain tissues. The Hendra, Nipah-Bangladesh, and Nipah-Malaysia strains caused severe respiratory and neurological disease with animals succumbing around 7 days post infection. Despite the presence of abundant viral shedding, animal-to-animal transmission did not occur. The host gene expression profiles of the lung tissue showed early activation of interferon responses and subsequent expression of inflammation-related genes that coincided with the clinical deterioration. Additionally, the lung tissue showed unchanged levels of lymphocyte markers and progressive downregulation of cell cycle genes and extracellular matrix components. Infection in the brain resulted in a limited breadth of the host responses, which is in accordance with the immunoprivileged status of this organ. Finally, we propose a model of the pathogenic mechanisms of henipavirus infection that integrates multiple components of the host responses.
Collapse
Affiliation(s)
- Alberto J. Leon
- Division of Experimental Therapeutics, Toronto General Research Institute, University Health Network, Toronto, Ontario, Canada
| | - Viktoriya Borisevich
- Department of Pathology, University of Texas Medical Branch, Galveston, TX, United States of America
- Microbiology & Immunology, University of Texas Medical Branch, Galveston, TX, United States of America
- Institute of Human Infections and Immunity, University of Texas Medical Branch, Galveston, TX, United States of America
| | - Nahal Boroumand
- Department of Pathology, University of Texas Medical Branch, Galveston, TX, United States of America
| | - Robert Seymour
- Department of Pathology, University of Texas Medical Branch, Galveston, TX, United States of America
- Institute of Human Infections and Immunity, University of Texas Medical Branch, Galveston, TX, United States of America
| | - Rebecca Nusbaum
- Department of Pathology, University of Texas Medical Branch, Galveston, TX, United States of America
| | - Olivier Escaffre
- Department of Pathology, University of Texas Medical Branch, Galveston, TX, United States of America
| | - Luoling Xu
- Division of Experimental Therapeutics, Toronto General Research Institute, University Health Network, Toronto, Ontario, Canada
| | - David J. Kelvin
- Department of Microbiology and Immunology, Dalhousie University, Halifax, Canada
- International Institute of Infection and Immunity, Shantou University Medical College, Shantou, PRC
- * E-mail: (DJK); (BR)
| | - Barry Rockx
- Department of Pathology, University of Texas Medical Branch, Galveston, TX, United States of America
- Microbiology & Immunology, University of Texas Medical Branch, Galveston, TX, United States of America
- Institute of Human Infections and Immunity, University of Texas Medical Branch, Galveston, TX, United States of America
- Department of Viroscience, Erasmus University Medical Center, Rotterdam, The Netherlands
- * E-mail: (DJK); (BR)
| |
Collapse
|
3
|
Kirkland PD, Gabor M, Poe I, Neale K, Chaffey K, Finlaison DS, Gu X, Hick PM, Read AJ, Wright T, Middleton D. Hendra Virus Infection in Dog, Australia, 2013. Emerg Infect Dis 2016; 21:2182-5. [PMID: 26583697 PMCID: PMC4672422 DOI: 10.3201/eid2112.151324] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Hendra virus occasionally causes severe disease in horses and humans. In Australia in 2013, infection was detected in a dog that had been in contact with an infected horse. Abnormalities and viral RNA were found in the dog's kidney, brain, lymph nodes, spleen, and liver. Dogs should be kept away from infected horses.
Collapse
|
4
|
Abstract
The genus Henipavirus within the family Paramyxoviridae includes the Hendra virus (HeV) and Nipah virus (NiV) which were discovered in the 1990s in Australia and Malaysia, respectively, after emerging to cause severe and often fatal outbreaks in humans and animals. While HeV is confined to Australia, more recent NiV outbreaks have been reported in Bangladesh, India and the Philippines. The clinical manifestations of both henipaviruses in humans appear similar, with a predominance of an acute encephalitic syndrome. Likewise, the pathological features are similar and characterized by disseminated, multi-organ vasculopathy comprising endothelial infection/ulceration, vasculitis, vasculitis-induced thrombosis/occlusion, parenchymal ischemia/microinfarction, and parenchymal cell infection in the central nervous system (CNS), lung, kidney and other major organs. This unique dual pathogenetic mechanism of vasculitis-induced microinfarction and neuronal infection causes severe tissue damage in the CNS. Both viruses can also cause relapsing encephalitis months and years after the acute infection. Many animal models studied to date have largely confirmed the pathology of henipavirus infection, and provided the means to test new therapeutic agents and vaccines. As the bat is the natural host of henipaviruses and has worldwide distribution, spillover events into human populations are expected to occur in the future.
Collapse
Affiliation(s)
- Kien Chai Ong
- Department of Biomedical ScienceFaculty of MedicineUniversity of MalayaKuala LumpurMalaysia
| | - Kum Thong Wong
- Department ofPathologyFaculty of MedicineUniversity of MalayaKuala LumpurMalaysia
| |
Collapse
|
5
|
Abstract
All seven recognized human cases of Hendra virus (HeV) infection have occurred in Queensland, Australia. Recognized human infections have all resulted from a HeV infected horse that was unusually efficient in transmitting the virus and a person with a high exposure to infectious secretions. In the large outbreak in Malaysia where Nipah virus (NiV) was first identified, most human infections resulted from close contact with NiV infected pigs. Outbreak investigations in Bangladesh have identified drinking raw date palm sap as the most common pathway of NiV transmission from Pteropus bats to people, but person-to-person transmission of NiV has been repeatedly identified in Bangladesh and India. Although henipaviruses are not easily transmitted to people, these newly recognized, high mortality agents warrant continued scientific attention.
Collapse
Affiliation(s)
- Stephen P Luby
- Department of Medicine, Stanford University, CA 94305, USA.
| | | |
Collapse
|
6
|
Abstract
Nipah (NiV) and Hendra (HeV) viruses are the deadliest human pathogens within the Paramyxoviridae family, which include human and animal pathogens of global biomedical importance. NiV and HeV infections cause respiratory and encephalitic illness with high mortality rates in humans. Henipaviruses (HNV) are the only Paramyxoviruses classified as biosafety level 4 (BSL4) pathogens due to their extreme pathogenicity, potential for bioterrorism, and lack of licensed vaccines and therapeutics. HNV use ephrin-B2 and ephrin-B3, highly conserved proteins, as viral entry receptors. This likely accounts for their unusually broad species tropism, and also provides opportunities to study how receptor usage, cellular tropism, and end-organ pathology relates to the pathobiology of HNV infections. The clinical and pathologic manifestations of NiV and HeV virus infections are reviewed in the chapters by Wong et al. and Geisbert et al. in this issue. Here, we will review the biology of the HNV receptors, and how receptor usage relates to HNV cell tropism in vitro and in vivo.
Collapse
Affiliation(s)
- Olivier Pernet
- Department of Microbiology, Immunology and Molecular Genetics, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095-1489, USA
| | | | | |
Collapse
|
7
|
Xu K, Chan YP, Rajashankar KR, Khetawat D, Yan L, Kolev MV, Broder CC, Nikolov DB. New insights into the Hendra virus attachment and entry process from structures of the virus G glycoprotein and its complex with Ephrin-B2. PLoS One 2012; 7:e48742. [PMID: 23144952 PMCID: PMC3489827 DOI: 10.1371/journal.pone.0048742] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2011] [Accepted: 09/30/2012] [Indexed: 01/07/2023] Open
Abstract
Hendra virus and Nipah virus, comprising the genus Henipavirus, are recently emerged, highly pathogenic and often lethal zoonotic agents against which there are no approved therapeutics. Two surface glycoproteins, the attachment (G) and fusion (F), mediate host cell entry. The crystal structures of the Hendra G glycoprotein alone and in complex with the ephrin-B2 receptor reveal that henipavirus uses Tryptophan 122 on ephrin-B2/B3 as a "latch" to facilitate the G-receptor association. Structural-based mutagenesis of residues in the Hendra G glycoprotein at the receptor binding interface document their importance for viral attachments and entry, and suggest that the stability of the Hendra-G-ephrin attachment complex does not strongly correlate with the efficiency of viral entry. In addition, our data indicates that conformational rearrangements of the G glycoprotein head domain upon receptor binding may be the trigger leading to the activation of the viral F fusion glycoprotein during virus infection.
Collapse
Affiliation(s)
- Kai Xu
- Structural Biology Program, Memorial Sloan-Kettering Cancer Center, New York, New York, United States of America
| | - Yee-Peng Chan
- Department of Microbiology and Immunology, Uniformed Services University, Bethesda, Maryland, United States of America
| | - Kanagalaghatta R. Rajashankar
- The Northeastern Collaborative Access Team, Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois, United States of America
| | - Dimple Khetawat
- Department of Microbiology and Immunology, Uniformed Services University, Bethesda, Maryland, United States of America
| | - Lianying Yan
- Department of Microbiology and Immunology, Uniformed Services University, Bethesda, Maryland, United States of America
| | - Momchil V. Kolev
- Structural Biology Program, Memorial Sloan-Kettering Cancer Center, New York, New York, United States of America
| | - Christopher C. Broder
- Department of Microbiology and Immunology, Uniformed Services University, Bethesda, Maryland, United States of America
| | - Dimitar B. Nikolov
- Structural Biology Program, Memorial Sloan-Kettering Cancer Center, New York, New York, United States of America
- * E-mail:
| |
Collapse
|
8
|
Snary EL, Ramnial V, Breed AC, Stephenson B, Field HE, Fooks AR. Qualitative release assessment to estimate the likelihood of henipavirus entering the United Kingdom. PLoS One 2012; 7:e27918. [PMID: 22328916 PMCID: PMC3273481 DOI: 10.1371/journal.pone.0027918] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2011] [Accepted: 10/27/2011] [Indexed: 11/25/2022] Open
Abstract
The genus Henipavirus includes Hendra virus (HeV) and Nipah virus (NiV), for which fruit bats (particularly those of the genus Pteropus) are considered to be the wildlife reservoir. The recognition of henipaviruses occurring across a wider geographic and host range suggests the possibility of the virus entering the United Kingdom (UK). To estimate the likelihood of henipaviruses entering the UK, a qualitative release assessment was undertaken. To facilitate the release assessment, the world was divided into four zones according to location of outbreaks of henipaviruses, isolation of henipaviruses, proximity to other countries where incidents of henipaviruses have occurred and the distribution of Pteropus spp. fruit bats. From this release assessment, the key findings are that the importation of fruit from Zone 1 and 2 and bat bushmeat from Zone 1 each have a Low annual probability of release of henipaviruses into the UK. Similarly, the importation of bat meat from Zone 2, horses and companion animals from Zone 1 and people travelling from Zone 1 and entering the UK was estimated to pose a Very Low probability of release. The annual probability of release for all other release routes was assessed to be Negligible. It is recommended that the release assessment be periodically re-assessed to reflect changes in knowledge and circumstances over time.
Collapse
Affiliation(s)
- Emma L Snary
- Centre for Epidemiology and Risk Analysis, Animal Health and Veterinary Laboratories Agency, Addlestone, Surrey, United Kingdom.
| | | | | | | | | | | |
Collapse
|
9
|
Abstract
Since the last major review on diagnosis of henipavirus infection about a decade ago, significant progress has been made in many different areas of test development, especially in the development of molecular tests using real-time PCR and many novel serological test platforms. In addition to provide an updated review of the current test capabilities, this review also identifies key future challenges in henipavirus diagnosis.
Collapse
Affiliation(s)
- Lin-Fa Wang
- CSRIO Livestock Industries, Australian Animal Health Laboratory, Geelong, VIC, Australia.
| | | |
Collapse
|
10
|
Factsheet: Hendra virus. N S W Public Health Bull 2011; 22:160-1. [PMID: 21982262 DOI: 10.1071/NB11031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
|
11
|
Daniels PW, Halpin K, Hyatt A, Middleton D. Infection and disease in reservoir and spillover hosts: determinants of pathogen emergence. Curr Top Microbiol Immunol 2007; 315:113-31. [PMID: 17848063 DOI: 10.1007/978-3-540-70962-6_6] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
Abstract
Infection and disease in reservoir and spillover hosts determine patterns of infectious agent availability and opportunities for infection, which then govern the process of transmission between susceptible species. In this chapter, using the zoonotic agents Hendra virus and Nipah virus as examples, the pathogenesis of infection in various species including the wildlife reservoirs and domestic spillover hosts is reviewed with an emphasis on the aspects of pathogenesis which contribute to the dissemination of infection. Through these discussions, the emergence of these zoonotic agents is explored.
Collapse
Affiliation(s)
- P W Daniels
- CSIRO Livestock Industries, Australian Animal Health Laboratory, Geelong, Australia.
| | | | | | | |
Collapse
|
12
|
Field HE, Breed AC, Shield J, Hedlefs RM, Pittard K, Pott B, Summers PM. Epidemiological perspectives on Hendra virus infection in horses and flying foxes. Aust Vet J 2007; 85:268-70. [PMID: 17615038 DOI: 10.1111/j.1751-0813.2007.00170.x] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- H E Field
- Department of Primary Industries and Fisheries, Yeerongpilly QLD 4105, Australia.
| | | | | | | | | | | | | |
Collapse
|
13
|
Whitman SD, Dutch RE. Surface density of the Hendra G protein modulates Hendra F protein-promoted membrane fusion: role for Hendra G protein trafficking and degradation. Virology 2007; 363:419-29. [PMID: 17328935 PMCID: PMC1952237 DOI: 10.1016/j.virol.2007.01.029] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2006] [Revised: 01/08/2007] [Accepted: 01/28/2007] [Indexed: 01/08/2023]
Abstract
Hendra virus, like most paramyxoviruses, requires both a fusion (F) and attachment (G) protein for promotion of cell-cell fusion. Recent studies determined that Hendra F is proteolytically processed by the cellular protease cathepsin L after endocytosis. This unique cathepsin L processing results in a small percentage of Hendra F on the cell surface. To determine how the surface densities of the two Hendra glycoproteins affect fusion promotion, we performed experiments that varied the levels of glycoproteins expressed in transfected cells. Using two different fusion assays, we found a marked increase in fusion when expression of the Hendra G protein was increased, with a 1:1 molar ratio of Hendra F:G on the cell surface resulting in optimal membrane fusion. Our results also showed that Hendra G protein levels are modulated by both more rapid protein turnover and slower protein trafficking than is seen for Hendra F.
Collapse
Affiliation(s)
| | - Rebecca Ellis Dutch
- *Corresponding author: Dr. Rebecca Ellis Dutch, Department of Molecular and Cellular Biochemistry, University of Kentucky, College of Medicine, Biomedical Biological Sciences Research Building, 741 South Limestone, Lexington, KY 40536-0509, Phone: (859) 323-1795, Fax: (859) 323-1037, E-mail:
| |
Collapse
|
14
|
Sawatsky B, Grolla A, Kuzenko N, Weingartl H, Czub M. Inhibition of henipavirus infection by Nipah virus attachment glycoprotein occurs without cell-surface downregulation of ephrin-B2 or ephrin-B3. J Gen Virol 2007; 88:582-591. [PMID: 17251577 DOI: 10.1099/vir.0.82427-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Nipah virus (NiV) and Hendra virus (HeV) are newly identified members of the family Paramyxoviridae and have been classified in the new genus Henipavirus based on unique genetic characteristics distinct from other paramyxoviruses. Transgenic cell lines were generated that expressed either the attachment protein (G) or the fusion protein (F) of NiV. Functional expression of NiV F and G was verified by complementation with the corresponding glycoprotein, which resulted in the development of syncytia. When exposed to NiV and HeV, expression of NiV G in Crandall feline kidney cells resulted in a qualitative inhibition of both cytopathic effect (CPE) and cell death by both viruses. RT-PCR analysis of surviving exposed cells showed a complete absence of viral positive-sense mRNA and genomic negative-sense viral RNA. Cells expressing NiV G were also unable to fuse with cells co-expressing NiV F and G in a fluorescent fusion inhibition assay. Cell-surface staining for the cellular receptors for NiV and HeV (ephrin-B2 and ephrin-B3) indicated that they were located on the surface of cells, regardless of NiV G expression or infection by NiV. These results indicated that viral interference can be established for henipaviruses and requires only the expression of the attachment protein, G. Furthermore, it was found that this interference probably occurs at the level of virus entry, as fusion was not observed in cells expressing NiV G. Finally, expression of NiV G by either transient transfection or NiV infection did not alter the cell-surface levels of the two known viral receptors.
Collapse
Affiliation(s)
- Bevan Sawatsky
- Department of Medical Microbiology, University of Manitoba, 730 William Avenue, Winnipeg, MB R3E 0W3, Canada
- National Microbiology Laboratory, Canadian Science Centre for Human and Animal Health, 1015 Arlington Street, Winnipeg, MB R3E 3R2, Canada
| | - Allen Grolla
- National Microbiology Laboratory, Canadian Science Centre for Human and Animal Health, 1015 Arlington Street, Winnipeg, MB R3E 3R2, Canada
| | - Nina Kuzenko
- Department of Medical Microbiology, University of Manitoba, 730 William Avenue, Winnipeg, MB R3E 0W3, Canada
- National Microbiology Laboratory, Canadian Science Centre for Human and Animal Health, 1015 Arlington Street, Winnipeg, MB R3E 3R2, Canada
| | - Hana Weingartl
- National Centre for Foreign Animal Disease, Canadian Science Centre for Human and Animal Health, 1015 Arlington Street, Winnipeg, MB R3E 3R2, Canada
- Department of Medical Microbiology, University of Manitoba, 730 William Avenue, Winnipeg, MB R3E 0W3, Canada
| | - Markus Czub
- Department of Medical Microbiology, University of Manitoba, 730 William Avenue, Winnipeg, MB R3E 0W3, Canada
- National Microbiology Laboratory, Canadian Science Centre for Human and Animal Health, 1015 Arlington Street, Winnipeg, MB R3E 3R2, Canada
| |
Collapse
|
15
|
Abstract
Two related, novel, zoonotic paramyxoviruses have been described recently. Hendra virus was first reported in horses and thence humans in Australia in 1994; Nipah virus was first reported in pigs and thence humans in Malaysia in 1998. Human cases of Nipah virus infection, apparently unassociated with infection in livestock, have been reported in Bangladesh since 2001. Species of fruit bats (genus Pteropus) have been identified as natural hosts of both agents. Anthropogenic changes (habitat loss, hunting) that have impacted the population dynamics of Pteropus species across much of their range are hypothesised to have facilitated emergence. Current strategies for the management of henipaviruses are directed at minimising contact with the natural hosts, monitoring identified intermediate hosts, improving biosecurity on farms, and better disease recognition and diagnosis. Investigation of the emergence and ecology of henipaviruses warrants a broad, cross-disciplinary ecosystem health approach that recognises the critical linkages between human activity, ecological change, and livestock and human health.
Collapse
Affiliation(s)
- James E. Childs
- Department of Epidemiology and Public Health and Center for Eco-Epidemiolog, Yale University School of Medicine, 60 College St, 208034, 06520-8034 New Haven, CT USA
| | - John S. Mackenzie
- Centre for Emerging Infectious Diseases, Australian Biosecurity Cooperative Research Centre, Curtin University of Technology, U1987, 6845 Perth, WA Australia
| | - Jürgen A. Richt
- Virus and Prion Diseases of Livestock Research Unit, National Animal Disease Center USDA, 2300 Dayton Ave Ames, 50010 IA USA
| |
Collapse
|
16
|
Abstract
Hendra and Nipah virus are closely related emerging viruses comprising the Henipavirus genus of the subfamily Paramyxovirinae and are distinguished by their ability to cause fatal disease in both animal and human hosts. In particular, the high mortality and person-to-person transmission associated with the most recent Nipah virus outbreaks, as well as the very recent re-emergence of Hendra virus, has confirmed the importance and necessity of developing effective therapeutic interventions. Much research conducted on the henipaviruses over the past several years has focused on virus entry, including the attachment of virus to the host cell, the identification of the virus receptor and the membrane fusion process between the viral and host cell membranes. These findings have led to the development of possible vaccine candidates, as well as potential antiviral therapeutics. The common link among all of the possible antiviral agents discussed here, which have also been developed and tested, is that they target very early stages of the infection process. The establishment and validation of suitable animal models of Henipavirus infection and pathogenesis are also discussed as they will be crucial in the assessment of the effectiveness of any treatments for Hendra and Nipah virus infection.
Collapse
Affiliation(s)
- Katharine N Bossart
- Australian Animal Health Laboratory, CSIRO Livestock Industries, Geelong, Victoria 3220, Australia.
| | | |
Collapse
|
17
|
Abstract
Within the past decade a number of new zoonotic paramyxoviruses emerged from flying foxes to cause serious disease outbreaks in man and livestock. Hendra virus was the cause of fatal infections of horses and man in Australia in 1994, 1999 and 2004. Nipah virus caused encephalitis in humans both in Malaysia in 1998/99, following silent spread of the virus in the pig population, and in Bangladesh from 2001 to 2004 probably as a result of direct bat to human transmission and spread within the human population. Hendra and Nipah viruses are highly pathogenic in humans with case fatality rates of 40% to 70%. Their genetic constitution, virulence and wide host range make them unique paramyxoviruses and they have been given Biosecurity Level 4 status in a new genus Henipavirus within the family Paramyxoviridae. Recent studies on the virulence, host range and cell tropisms of henipaviruses provide insights into the unique biological properties of these emerging human pathogens and suggest approaches for vaccine development and therapeutic countermeasures.
Collapse
Affiliation(s)
- Bryan T Eaton
- Australian Animal Health Laboratory, CSIRO, 5 Portarlington Road, Geelong, Victoria 3220, Australia.
| | | | | |
Collapse
|
18
|
Abstract
Hendra virus and Nipah virus are highly pathogenic paramyxoviruses that have recently emerged from flying foxes to cause serious disease outbreaks in humans and livestock in Australia, Malaysia, Singapore and Bangladesh. Their unique genetic constitution, high virulence and wide host range set them apart from other paramyxoviruses. These features led to their classification into the new genus Henipavirus within the family Paramyxoviridae and to their designation as Biosafety Level 4 pathogens. This review provides an overview of henipaviruses and the types of infection they cause, and describes how studies on the structure and function of henipavirus proteins expressed from cloned genes have provided insights into the unique biological properties of these emerging human pathogens.
Collapse
Affiliation(s)
- Bryan T Eaton
- Australian Animal Health Laboratory, Commonwealth Scientific and Industrial Research Organization, 5 Portarlington Road, Geelong, Victoria 3220, Australia.
| | | | | | | |
Collapse
|
19
|
Bossart KN, Crameri G, Dimitrov AS, Mungall BA, Feng YR, Patch JR, Choudhary A, Wang LF, Eaton BT, Broder CC. Receptor binding, fusion inhibition, and induction of cross-reactive neutralizing antibodies by a soluble G glycoprotein of Hendra virus. J Virol 2005; 79:6690-702. [PMID: 15890907 PMCID: PMC1112112 DOI: 10.1128/jvi.79.11.6690-6702.2005] [Citation(s) in RCA: 130] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Hendra virus (HeV) and Nipah virus (NiV) are closely related emerging viruses comprising the Henipavirus genus of the Paramyxovirinae, which are distinguished by their ability to cause fatal disease in both animal and human hosts. These viruses infect cells by a pH-independent membrane fusion event mediated by their attachment (G) and fusion (F) glycoproteins. Previously, we reported on HeV- and NiV-mediated fusion activities and detailed their host-cell tropism characteristics. These studies also suggested that a common cell surface receptor, which could be destroyed by protease, was utilized by both viruses. To further characterize the G glycoprotein and its unknown receptor, soluble forms of HeV G (sG) were constructed by replacing its cytoplasmic tail and transmembrane domains with an immunoglobulin kappa leader sequence coupled to either an S-peptide tag (sG(S-tag)) or myc-epitope tag (sG(myc-tag)) to facilitate purification and detection. Expression of sG was verified in cell lysates and culture supernatants by specific affinity precipitation. Analysis of sG by size exclusion chromatography and sucrose gradient centrifugation demonstrated tetrameric, dimeric, and monomeric species, with the majority of the sG released as a disulfide-linked dimer. Immunofluorescence staining revealed that sG specifically bound to HeV and NiV infection-permissive cells but not to a nonpermissive HeLa cell line clone, suggesting that it binds to virus receptor on host cells. Preincubation of host cells with sG resulted in dose-dependent inhibition of both HeV and NiV cell fusion as well as infection by live virus. Taken together, these data indicate that sG retains important native structural features, and we further demonstrate that administration of sG to rabbits can elicit a potent cross-reactive neutralizing antibody response against infectious HeV and NiV. This HeV sG glycoprotein will be exceedingly useful for structural studies, receptor identification strategies, and vaccine development goals for these important emerging viral agents.
Collapse
Affiliation(s)
- Katharine N Bossart
- Department of Microbiology and Immunology, F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, 4301 Jones Bridge Road, Bethesda, MD 20814-4799, USA
| | | | | | | | | | | | | | | | | | | |
Collapse
|
20
|
Lange C, Schütt M, Brodt HR. [Emerging respiratory infections caused by pneumotropic viruses]. Dtsch Med Wochenschr 2005; 130:1385-91. [PMID: 15915382 DOI: 10.1055/s-2005-868739] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Affiliation(s)
- C Lange
- Medizinische Klinik, Forschungszentrum Borstel.
| | | | | |
Collapse
|
21
|
Abstract
The last three decades have seen an alarming number of high-profile outbreaks of new viruses and other pathogens, many of them emerging from wildlife. Recent outbreaks of SARS, avian influenza, and others highlight emerging zoonotic diseases as one of the key threats to global health. Similar emerging diseases have been reported in wildlife populations, resulting in mass mortalities, population declines, and even extinctions. In this paper, we highlight three examples of emerging pathogens: Nipah and Hendra virus, which emerged in Malaysia and Australia in the 1990s respectively, with recent outbreaks caused by similar viruses in India in 2000 and Bangladesh in 2004; West Nile virus, which emerged in the New World in 1999; and amphibian chytridiomycosis, which has emerged globally as a threat to amphibian populations and a major cause of amphibian population declines. We discuss a new, conservation medicine approach to emerging diseases that integrates veterinary, medical, ecologic, and other sciences in interdisciplinary teams. These teams investigate the causes of emergence, analyze the underlying drivers, and attempt to define common rules governing emergence for human, wildlife, and plant EIDs. The ultimate goal is a risk analysis that allows us to predict future emergence of known and unknown pathogens.
Collapse
Affiliation(s)
- Peter Daszak
- Consortium for Conservation Medicine, Wildlife Trust, 61 Route 9W, Palisades, NY, USA.
| | | | | | | | | |
Collapse
|
22
|
Abstract
Hendra virus is a new virus of the family Paramyxoviridae. This virus was first detected in Queensland, Australia, in 1994; although, it seems that the virus has infected fruit-eating bats (flying-foxes) for a very long time. At least 2 humans and 15 horses have been killed by this virus since it first emerged as a virus that may infect mammals other than flying-foxes. Hendra virus is thought to have moved from flying-foxes to horses, and then from horses to people. There is a reasonably strong hypothesis for horse-to-human transmission: transmission of virus via nasal discharge, saliva and/or urine. In contrast, there is no strong hypothesis for flying-fox-to-human transmission. I present evidence that the Australian paralysis tick, Ixodes holocyclus, which has apparently only recently become a parasite of flying-foxes, may transmit Hendra virus and perhaps related viruses from flying-foxes to horses and other mammals.
Collapse
Affiliation(s)
- S C Barker
- Department of Microbiology and Parisitology, Institute for Molecular Biosciences, ARC Special Research Center for Functional and Applied Genomics, The University of Queensland, Brisbane, Australia.
| |
Collapse
|