1
|
Wanninger TG, Millian DE, Saldarriaga OA, Maruyama J, Saito T, Reyna RA, Taniguchi S, Arroyave E, Connolly ME, Stevenson HL, Paessler S. Macrophage infection, activation, and histopathological findings in ebolavirus infection. Front Cell Infect Microbiol 2022; 12:1023557. [PMID: 36310868 PMCID: PMC9597316 DOI: 10.3389/fcimb.2022.1023557] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Accepted: 09/15/2022] [Indexed: 12/05/2022] Open
Abstract
Macrophages contribute to Ebola virus disease through their susceptibility to direct infection, their multi-faceted response to ebolaviruses, and their association with pathological findings in tissues throughout the body. Viral attachment and entry factors, as well as the more recently described influence of cell polarization, shape macrophage susceptibility to direct infection. Moreover, the study of Toll-like receptor 4 and the RIG-I-like receptor pathway in the macrophage response to ebolaviruses highlight important immune signaling pathways contributing to the breadth of macrophage responses. Lastly, the deep histopathological catalogue of macrophage involvement across numerous tissues during infection has been enriched by descriptions of tissues involved in sequelae following acute infection, including: the eye, joints, and the nervous system. Building upon this knowledge base, future opportunities include characterization of macrophage phenotypes beneficial or deleterious to survival, delineation of the specific roles macrophages play in pathological lesion development in affected tissues, and the creation of macrophage-specific therapeutics enhancing the beneficial activities and reducing the deleterious contributions of macrophages to the outcome of Ebola virus disease.
Collapse
Affiliation(s)
- Timothy G. Wanninger
- Department of Pathology, University of Texas Medical Branch, Galveston, TX, United States
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX, United States
| | - Daniel E. Millian
- Department of Pathology, University of Texas Medical Branch, Galveston, TX, United States
| | - Omar A. Saldarriaga
- Department of Pathology, University of Texas Medical Branch, Galveston, TX, United States
| | - Junki Maruyama
- Department of Pathology, University of Texas Medical Branch, Galveston, TX, United States
| | - Takeshi Saito
- Department of Pathology, University of Texas Medical Branch, Galveston, TX, United States
| | - Rachel A. Reyna
- Department of Pathology, University of Texas Medical Branch, Galveston, TX, United States
| | - Satoshi Taniguchi
- Department of Pathology, University of Texas Medical Branch, Galveston, TX, United States
| | - Esteban Arroyave
- Department of Pathology, University of Texas Medical Branch, Galveston, TX, United States
| | - Melanie E. Connolly
- Department of Surgery, University of Texas Medical Branch, Galveston, TX, United States
| | - Heather L. Stevenson
- Department of Pathology, University of Texas Medical Branch, Galveston, TX, United States
| | - Slobodan Paessler
- Department of Pathology, University of Texas Medical Branch, Galveston, TX, United States
| |
Collapse
|
2
|
Escaffre O, Juelich TL, Neef N, Massey S, Smith J, Brasel T, Smith JK, Kalveram B, Zhang L, Perez D, Ikegami T, Freiberg AN, Comer JE. STAT-1 Knockout Mice as a Model for Wild-Type Sudan Virus (SUDV). Viruses 2021; 13:v13071388. [PMID: 34372594 PMCID: PMC8310124 DOI: 10.3390/v13071388] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Revised: 07/14/2021] [Accepted: 07/16/2021] [Indexed: 12/03/2022] Open
Abstract
Currently there is no FDA-licensed vaccine or therapeutic against Sudan ebolavirus (SUDV) infections. The largest ever reported 2014–2016 West Africa outbreak, as well as the 2021 outbreak in the Democratic Republic of Congo, highlight the critical need for countermeasures against filovirus infections. A well-characterized small animal model that is susceptible to wild-type filoviruses would greatly add to the screening of antivirals and vaccines. Here, we infected signal transducer and activator of transcription-1 knock out (STAT-1 KO) mice with five different wildtype filoviruses to determine susceptibility. SUDV and Marburg virus (MARV) were the most virulent, and caused 100% or 80% lethality, respectively. Zaire ebolavirus (EBOV), Bundibugyo ebolavirus (BDBV), and Taï Forest ebolavirus (TAFV) caused 40%, 20%, and no mortality, respectively. Further characterization of SUDV in STAT-1 KO mice demonstrated lethality down to 3.1 × 101 pfu. Viral genomic material was detectable in serum as early as 1 to 2 days post-challenge. The onset of viremia was closely followed by significant changes in total white blood cells and proportion of neutrophils and lymphocytes, as well as by an influx of neutrophils in the liver and spleen. Concomitant significant fluctuations in blood glucose, albumin, globulin, and alanine aminotransferase were also noted, altogether consistent with other models of filovirus infection. Finally, favipiravir treatment fully protected STAT-1 KO mice from lethal SUDV challenge, suggesting that this may be an appropriate small animal model to screen anti-SUDV countermeasures.
Collapse
Affiliation(s)
- Olivier Escaffre
- Department of Pathology, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA; (O.E.); (T.L.J.); (J.K.S.); (B.K.); (L.Z.); (T.I.)
| | - Terry L. Juelich
- Department of Pathology, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA; (O.E.); (T.L.J.); (J.K.S.); (B.K.); (L.Z.); (T.I.)
| | - Natasha Neef
- XTR Toxicologic Pathology Services LLC, Sterling, VA 20165, USA;
| | - Shane Massey
- Office of Regulated Nonclinical Studies, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA; (S.M.); (J.S.); (T.B.)
| | - Jeanon Smith
- Office of Regulated Nonclinical Studies, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA; (S.M.); (J.S.); (T.B.)
| | - Trevor Brasel
- Office of Regulated Nonclinical Studies, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA; (S.M.); (J.S.); (T.B.)
- Department of Microbiology and Immunology, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA
- The Center for Biodefense and Emerging Infectious Diseases, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA
| | - Jennifer K. Smith
- Department of Pathology, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA; (O.E.); (T.L.J.); (J.K.S.); (B.K.); (L.Z.); (T.I.)
| | - Birte Kalveram
- Department of Pathology, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA; (O.E.); (T.L.J.); (J.K.S.); (B.K.); (L.Z.); (T.I.)
| | - Lihong Zhang
- Department of Pathology, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA; (O.E.); (T.L.J.); (J.K.S.); (B.K.); (L.Z.); (T.I.)
| | - David Perez
- Texas A&M University Division of Research, Texas A&M University, College Station, TX 77843, USA;
| | - Tetsuro Ikegami
- Department of Pathology, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA; (O.E.); (T.L.J.); (J.K.S.); (B.K.); (L.Z.); (T.I.)
- The Center for Biodefense and Emerging Infectious Diseases, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA
- Sealy Institute for Vaccine Sciences, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA
- Institute for Human Infections and Immunity, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA
| | - Alexander N. Freiberg
- Department of Pathology, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA; (O.E.); (T.L.J.); (J.K.S.); (B.K.); (L.Z.); (T.I.)
- The Center for Biodefense and Emerging Infectious Diseases, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA
- Sealy Institute for Vaccine Sciences, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA
- Institute for Human Infections and Immunity, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA
- Correspondence: (A.N.F.); (J.E.C.)
| | - Jason E. Comer
- Office of Regulated Nonclinical Studies, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA; (S.M.); (J.S.); (T.B.)
- Department of Microbiology and Immunology, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA
- The Center for Biodefense and Emerging Infectious Diseases, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA
- Institute of Translational Sciences, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA
- Correspondence: (A.N.F.); (J.E.C.)
| |
Collapse
|
3
|
Kikwit Ebola Virus Disease Progression in the Rhesus Monkey Animal Model. Viruses 2020; 12:v12070753. [PMID: 32674252 PMCID: PMC7411891 DOI: 10.3390/v12070753] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Revised: 07/03/2020] [Accepted: 07/06/2020] [Indexed: 12/23/2022] Open
Abstract
Ongoing Ebola virus disease outbreaks in the Democratic Republic of the Congo follow the largest recorded outbreak in Western Africa (2013–2016). To combat outbreaks, testing of medical countermeasures (therapeutics or vaccines) requires a well-defined, reproducible, animal model. Here we present Ebola virus disease kinetics in 24 Chinese-origin rhesus monkeys exposed intramuscularly to a highly characterized, commercially available Kikwit Ebola virus Filovirus Animal Non-Clinical Group (FANG) stock. Until reaching predetermined clinical disease endpoint criteria, six animals underwent anesthesia for repeated clinical sampling and were compared to six that did not. Groups of three animals were euthanized and necropsied on days 3, 4, 5, and 6 post-exposure, respectively. In addition, three uninfected animals served as controls. Here, we present detailed characterization of clinical and laboratory disease kinetics and complete blood counts, serum chemistries, Ebola virus titers, and disease kinetics for future medical countermeasure (MCM) study design and control data. We measured no statistical difference in hematology, chemistry values, or time to clinical endpoint in animals that were anesthetized for clinical sampling during the acute disease compared to those that were not.
Collapse
|
4
|
Clinical, Histopathologic, and Immunohistochemical Characterization of Experimental Marburg Virus Infection in A Natural Reservoir Host, the Egyptian Rousette Bat ( Rousettus aegyptiacus). Viruses 2019; 11:v11030214. [PMID: 30832364 PMCID: PMC6466277 DOI: 10.3390/v11030214] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2019] [Revised: 02/26/2019] [Accepted: 02/27/2019] [Indexed: 01/22/2023] Open
Abstract
Egyptian rousette bats (Rousettus aegyptiacus) are natural reservoir hosts of Marburg virus (MARV), and Ravn virus (RAVV; collectively called marburgviruses) and have been linked to human cases of Marburg virus disease (MVD). We investigated the clinical and pathologic effects of experimental MARV infection in Egyptian rousettes through a serial euthanasia study and found clear evidence of mild but transient disease. Three groups of nine, captive-born, juvenile male bats were inoculated subcutaneously with 10,000 TCID50 of Marburg virus strain Uganda 371Bat2007, a minimally passaged virus originally isolated from a wild Egyptian rousette. Control bats (n = 3) were mock-inoculated. Three animals per day were euthanized at 3, 5⁻10, 12 and 28 days post-inoculation (DPI); controls were euthanized at 28 DPI. Blood chemistry analyses showed a mild, statistically significant elevation in alanine aminotransferase (ALT) at 3, 6 and 7 DPI. Lymphocyte and monocyte counts were mildly elevated in inoculated bats after 9 DPI. Liver histology revealed small foci of inflammatory infiltrate in infected bats, similar to lesions previously described in wild, naturally-infected bats. Liver lesion severity scores peaked at 7 DPI, and were correlated with both ALT and hepatic viral RNA levels. Immunohistochemical staining detected infrequent viral antigen in liver (3⁻8 DPI, n = 8), spleen (3⁻7 DPI, n = 8), skin (inoculation site; 3⁻12 DPI, n = 20), lymph nodes (3⁻10 DPI, n = 6), and oral submucosa (8⁻9 DPI, n = 2). Viral antigen was present in histiocytes, hepatocytes and mesenchymal cells, and in the liver, antigen staining co-localized with inflammatory foci. These results show the first clear evidence of very mild disease caused by a filovirus in a reservoir bat host and provide support for our experimental model of this virus-reservoir host system.
Collapse
|
5
|
Comer JE, Escaffre O, Neef N, Brasel T, Juelich TL, Smith JK, Smith J, Kalveram B, Perez DD, Massey S, Zhang L, Freiberg AN. Filovirus Virulence in Interferon α/β and γ Double Knockout Mice, and Treatment with Favipiravir. Viruses 2019; 11:v11020137. [PMID: 30717492 PMCID: PMC6410141 DOI: 10.3390/v11020137] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2019] [Revised: 01/25/2019] [Accepted: 01/30/2019] [Indexed: 02/07/2023] Open
Abstract
The 2014 Ebolavirus outbreak in West Africa highlighted the need for vaccines and therapeutics to prevent and treat filovirus infections. A well-characterized small animal model that is susceptible to wild-type filoviruses would facilitate the screening of anti-filovirus agents. To that end, we characterized knockout mice lacking α/β and γ interferon receptors (IFNAGR KO) as a model for wild-type filovirus infection. Intraperitoneal challenge of IFNAGR KO mice with several known human pathogenic species from the genus Ebolavirus and Marburgvirus, except Bundibugyo ebolavirus and Taï Forest ebolavirus, caused variable mortality rate. Further characterization of the prototype Ebola virus Kikwit isolate infection in this KO mouse model showed 100% lethality down to a dilution equivalent to 1.0 × 10−1 pfu with all deaths occurring between 7 and 9 days post-challenge. Viral RNA was detectable in serum after challenge with 1.0 × 102 pfu as early as one day after infection. Changes in hematology and serum chemistry became pronounced as the disease progressed and mirrored the histological changes in the spleen and liver that were also consistent with those described for patients with Ebola virus disease. In a proof-of-principle study, treatment of Ebola virus infected IFNAGR KO mice with favipiravir resulted in 83% protection. Taken together, the data suggest that IFNAGR KO mice may be a useful model for early screening of anti-filovirus medical countermeasures.
Collapse
Affiliation(s)
- Jason E Comer
- Department of Microbiology and Immunology, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA.
- Office of Regulated Nonclinical Studies, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA.
- Sealy Institute for Vaccine Science, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA.
- The Center for Biodefense and Emerging Infectious Diseases, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA.
| | - Olivier Escaffre
- Department of Pathology, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA.
| | - Natasha Neef
- Experimental Pathology Laboratories, Inc., Sterling, VA 20167, USA.
| | - Trevor Brasel
- Department of Microbiology and Immunology, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA.
- Office of Regulated Nonclinical Studies, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA.
- Sealy Institute for Vaccine Science, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA.
| | - Terry L Juelich
- Department of Pathology, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA.
| | - Jennifer K Smith
- Department of Pathology, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA.
| | - Jeanon Smith
- Office of Regulated Nonclinical Studies, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA.
| | - Birte Kalveram
- Department of Pathology, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA.
| | - David D Perez
- Department of Pathology, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA.
| | - Shane Massey
- Office of Regulated Nonclinical Studies, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA.
| | - Lihong Zhang
- Department of Pathology, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA.
| | - Alexander N Freiberg
- Sealy Institute for Vaccine Science, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA.
- The Center for Biodefense and Emerging Infectious Diseases, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA.
- Department of Pathology, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA.
- Institute for Human Infections and Immunity, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA.
| |
Collapse
|
6
|
Affiliation(s)
- D K Meyerholz
- 1 Department of Pathology, Roy J. and Lucille A. Carver College of Medicine, Iowa City, IA, USA
| | - H A Flaherty
- 2 Department of Veterinary Pathology, Iowa State University, Ames, IA, USA
| |
Collapse
|
7
|
Cooper TK, Huzella L, Johnson JC, Rojas O, Yellayi S, Sun MG, Bavari S, Bonilla A, Hart R, Jahrling PB, Kuhn JH, Zeng X. Histology, immunohistochemistry, and in situ hybridization reveal overlooked Ebola virus target tissues in the Ebola virus disease guinea pig model. Sci Rep 2018; 8:1250. [PMID: 29352230 PMCID: PMC5775334 DOI: 10.1038/s41598-018-19638-x] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2017] [Accepted: 01/02/2018] [Indexed: 12/20/2022] Open
Abstract
Survivors of Ebola virus infection may become subclinically infected, but whether animal models recapitulate this complication is unclear. Using histology in combination with immunohistochemistry and in situ hybridization in a retrospective review of a guinea pig confirmation-of-virulence study, we demonstrate for the first time Ebola virus infection in hepatic oval cells, the endocardium and stroma of the atrioventricular valves and chordae tendinae, satellite cells of peripheral ganglia, neurofibroblasts and Schwann cells of peripheral nerves and ganglia, smooth muscle cells of the uterine myometrium and vaginal wall, acini of the parotid salivary glands, thyroid follicular cells, adrenal medullary cells, pancreatic islet cells, endometrial glandular and surface epithelium, and the epithelium of the vagina, penis and, prepuce. These findings indicate that standard animal models for Ebola virus disease are not as well-described as previously thought and may serve as a stepping stone for future identification of potential sites of virus persistence.
Collapse
Affiliation(s)
- Timothy K Cooper
- Integrated Research Facility at Fort Detrick, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Fort Detrick, Frederick, Maryland, USA.
| | - Louis Huzella
- Integrated Research Facility at Fort Detrick, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Fort Detrick, Frederick, Maryland, USA
| | - Joshua C Johnson
- Integrated Research Facility at Fort Detrick, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Fort Detrick, Frederick, Maryland, USA
| | - Oscar Rojas
- Integrated Research Facility at Fort Detrick, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Fort Detrick, Frederick, Maryland, USA
| | - Sri Yellayi
- Integrated Research Facility at Fort Detrick, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Fort Detrick, Frederick, Maryland, USA
- Path-2-Gene, LLC, Harrisburg, PA, USA
| | - Mei G Sun
- United States Army Medical Research Institute of Infectious Diseases, Fort Detrick, Frederick, Maryland, USA
| | - Sina Bavari
- United States Army Medical Research Institute of Infectious Diseases, Fort Detrick, Frederick, Maryland, USA
| | - Amanda Bonilla
- Integrated Research Facility at Fort Detrick, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Fort Detrick, Frederick, Maryland, USA
| | - Randy Hart
- Integrated Research Facility at Fort Detrick, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Fort Detrick, Frederick, Maryland, USA
| | - Peter B Jahrling
- Integrated Research Facility at Fort Detrick, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Fort Detrick, Frederick, Maryland, USA
| | - Jens H Kuhn
- Integrated Research Facility at Fort Detrick, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Fort Detrick, Frederick, Maryland, USA
| | - Xiankun Zeng
- United States Army Medical Research Institute of Infectious Diseases, Fort Detrick, Frederick, Maryland, USA.
| |
Collapse
|
8
|
Cashman KA, Wilkinson ER, Wollen SE, Shamblin JD, Zelko JM, Bearss JJ, Zeng X, Broderick KE, Schmaljohn CS. DNA vaccines elicit durable protective immunity against individual or simultaneous infections with Lassa and Ebola viruses in guinea pigs. Hum Vaccin Immunother 2017; 13:3010-3019. [PMID: 29135337 PMCID: PMC5718824 DOI: 10.1080/21645515.2017.1382780] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
We previously developed optimized DNA vaccines against both Lassa fever and Ebola hemorrhagic fever viruses and demonstrated that they were protective individually in guinea pig and nonhuman primate models. In this study, we vaccinated groups of strain 13 guinea pigs two times, four weeks apart with 50 µg of each DNA vaccine or a mock vaccine at discrete sites by intradermal electroporation. Five weeks following the second vaccinations, guinea pigs were exposed to lethal doses of Lassa virus, Ebola virus, or a combination of both viruses simultaneously. None of the vaccinated guinea pigs, regardless of challenge virus and including the coinfected group, displayed weight loss, fever or other disease signs, and all survived to the study endpoint. All of the mock-vaccinated guinea pigs that were infected with Lassa virus, and all but one of the EBOV-infected mock-vaccinated guinea pigs succumbed. In order to determine if the dual-agent vaccination strategy could protect against both viruses if exposures were temporally separated, we held the surviving vaccinates in BSL-4 for approximately 120 days to perform a cross-challenge experiment in which guinea pigs originally infected with Lassa virus received a lethal dose of Ebola virus and those originally infected with Ebola virus were infected with a lethal dose of Lassa virus. All guinea pigs remained healthy and survived to the study endpoint. This study clearly demonstrates that DNA vaccines against Lassa and Ebola viruses can elicit protective immunity against both individual virus exposures as well as in a mixed-infection environment.
Collapse
Affiliation(s)
- Kathleen A Cashman
- a Virology Division, United States Army Medical Research Institute of Infectious diseases (USAMRIID) , Fort Detrick , MD
| | - Eric R Wilkinson
- a Virology Division, United States Army Medical Research Institute of Infectious diseases (USAMRIID) , Fort Detrick , MD
| | - Suzanne E Wollen
- a Virology Division, United States Army Medical Research Institute of Infectious diseases (USAMRIID) , Fort Detrick , MD
| | - Joshua D Shamblin
- a Virology Division, United States Army Medical Research Institute of Infectious diseases (USAMRIID) , Fort Detrick , MD
| | - Justine M Zelko
- a Virology Division, United States Army Medical Research Institute of Infectious diseases (USAMRIID) , Fort Detrick , MD
| | - Jeremy J Bearss
- b Pathology Division, United States Army Medical Research Institute of Infectious diseases (USAMRIID) , Fort Detrick , MD
| | - Xiankun Zeng
- b Pathology Division, United States Army Medical Research Institute of Infectious diseases (USAMRIID) , Fort Detrick , MD
| | | | - Connie S Schmaljohn
- d Office of the Chief Scientists, Headquarters, USAMRIID , Fort Detrick , MD
| |
Collapse
|
9
|
More S, Bøtner A, Butterworth A, Calistri P, Depner K, Edwards S, Garin-Bastuji B, Good M, Gortázar Schmidt C, Michel V, Miranda MA, Nielsen SS, Raj M, Sihvonen L, Spoolder H, Stegeman JA, Thulke HH, Velarde A, Willeberg P, Winckler C, Baldinelli F, Broglia A, Beltrán Beck B, Kohnle L, Morgado J, Bicout D. Assessment of listing and categorisation of animal diseases within the framework of the Animal Health Law (Regulation (EU) No 2016/429): Ebola virus disease. EFSA J 2017; 15:e04890. [PMID: 32625555 PMCID: PMC7009972 DOI: 10.2903/j.efsa.2017.4890] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Ebola virus disease has been assessed according to the criteria of the Animal Health Law (AHL), in particular criteria of Article 7 on disease profile and impacts, Article 5 on the eligibility of Ebola virus disease to be listed, Article 9 for the categorisation of Ebola virus disease according to disease prevention and control rules as in Annex IV and Article 8 on the list of animal species related to Ebola virus disease. The assessment has been performed following a methodology composed of information collection and compilation, expert judgement on each criterion at individual and, if no consensus was reached before, also at collective level. The output is composed of the categorical answer, and for the questions where no consensus was reached, the different supporting views are reported. Details on the methodology used for this assessment are explained in a separate opinion. According to the assessment performed, Ebola virus disease can be considered eligible to be listed for Union intervention as laid down in Article 5(3) of the AHL. The disease would comply with the criteria as in Sections 4 and 5 of Annex IV of the AHL, for the application of the disease prevention and control rules referred to in points (d) and (e) of Article 9(1). The animal species to be listed for Ebola virus disease according to Article 8(3) criteria are some species of non-human primates, pigs and rodents as susceptible species and some species of fruit bats as reservoir, as indicated in the present opinion.
Collapse
|
10
|
Biava M, Caglioti C, Bordi L, Castilletti C, Colavita F, Quartu S, Nicastri E, Lauria FN, Petrosillo N, Lanini S, Hoenen T, Kobinger G, Zumla A, Di Caro A, Ippolito G, Capobianchi MR, Lalle E. Detection of Viral RNA in Tissues following Plasma Clearance from an Ebola Virus Infected Patient. PLoS Pathog 2017; 13:e1006065. [PMID: 28056096 PMCID: PMC5215833 DOI: 10.1371/journal.ppat.1006065] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Accepted: 11/14/2016] [Indexed: 12/29/2022] Open
Abstract
An unprecedented Ebola virus (EBOV) epidemic occurred in 2013–2016 in West Africa. Over this time the epidemic exponentially grew and moved to Europe and North America, with several imported cases and many Health Care Workers (HCW) infected. Better understanding of EBOV infection patterns in different body compartments is mandatory to develop new countermeasures, as well as to fully comprehend the pathways of human-to-human transmission. We have longitudinally explored the persistence of EBOV-specific negative sense genomic RNA (neg-RNA) and the presence of positive sense RNA (pos-RNA), including both replication intermediate (antigenomic-RNA) and messenger RNA (mRNA) molecules, in the upper and lower respiratory tract, as compared to plasma, in a HCW infected with EBOV in Sierra Leone, who was hospitalized in the high isolation facility of the National Institute for Infectious Diseases “Lazzaro Spallanzani” (INMI), Rome, Italy. We observed persistence of pos-RNA and neg-RNAs in longitudinally collected specimens of the lower respiratory tract, even after viral clearance from plasma, suggesting possible local replication. The purpose of the present study is to enhance the knowledge on the biological features of EBOV that can contribute to the human-to-human transmissibility and to develop effective intervention strategies. However, further investigation is needed in order to better understand the clinical meaning of viral replication and shedding in the respiratory tract. An unprecedented Ebola outbreak occurred in 2013–2016 in West Africa. In order to better understand EBOV infection patterns in different body compartments, we have longitudinally explored the presence of already assessed markers of ongoing EBOV replication (negative sense genomic RNA and positive sense RNA) in the upper and lower respiratory tract, as compared to plasma and other body compartments, in a Health Care Worker infected with EBOV in Sierra Leone, who was hospitalized in the high isolation facility of the National Institute for Infectious Diseases “Lazzaro Spallanzani” (INMI), Rome, Italy. The presence of total EBOV RNA and replication markers was observed in specimens of the lower respiratory tract, even after viral clearance from plasma, suggesting possible local replication. Our results contribute to the knowledge on the biological features of EBOV and shed light on the potential role of respiratory compartment in human-to-human transmissibility.
Collapse
Affiliation(s)
- Mirella Biava
- National Institute for Infectious Diseases “Lazzaro Spallanzani” IRCCS, Via Portuense, Rome, Italy
| | - Claudia Caglioti
- National Institute for Infectious Diseases “Lazzaro Spallanzani” IRCCS, Via Portuense, Rome, Italy
| | - Licia Bordi
- National Institute for Infectious Diseases “Lazzaro Spallanzani” IRCCS, Via Portuense, Rome, Italy
| | - Concetta Castilletti
- National Institute for Infectious Diseases “Lazzaro Spallanzani” IRCCS, Via Portuense, Rome, Italy
| | - Francesca Colavita
- National Institute for Infectious Diseases “Lazzaro Spallanzani” IRCCS, Via Portuense, Rome, Italy
| | - Serena Quartu
- National Institute for Infectious Diseases “Lazzaro Spallanzani” IRCCS, Via Portuense, Rome, Italy
| | - Emanuele Nicastri
- National Institute for Infectious Diseases “Lazzaro Spallanzani” IRCCS, Via Portuense, Rome, Italy
| | - Francesco Nicola Lauria
- National Institute for Infectious Diseases “Lazzaro Spallanzani” IRCCS, Via Portuense, Rome, Italy
- International Public Health Crisis Group (IPHCG)
| | - Nicola Petrosillo
- National Institute for Infectious Diseases “Lazzaro Spallanzani” IRCCS, Via Portuense, Rome, Italy
| | - Simone Lanini
- National Institute for Infectious Diseases “Lazzaro Spallanzani” IRCCS, Via Portuense, Rome, Italy
- International Public Health Crisis Group (IPHCG)
| | - Thomas Hoenen
- Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, Federal Research Institute for Animal HealthInsel Riems, Germany
| | - Gary Kobinger
- International Public Health Crisis Group (IPHCG)
- Research Centre on Infectious Diseases, Faculty of Medicine, Université Laval, Québec Canada
| | - Alimuddin Zumla
- International Public Health Crisis Group (IPHCG)
- University College London and NIHR Biomedical Research Centre, University College London Hospitals NHS Foundation Trust, London, United Kingdom
| | - Antonino Di Caro
- National Institute for Infectious Diseases “Lazzaro Spallanzani” IRCCS, Via Portuense, Rome, Italy
- International Public Health Crisis Group (IPHCG)
| | - Giuseppe Ippolito
- National Institute for Infectious Diseases “Lazzaro Spallanzani” IRCCS, Via Portuense, Rome, Italy
- International Public Health Crisis Group (IPHCG)
- * E-mail:
| | | | - Eleonora Lalle
- National Institute for Infectious Diseases “Lazzaro Spallanzani” IRCCS, Via Portuense, Rome, Italy
| |
Collapse
|
11
|
Burk R, Bollinger L, Johnson JC, Wada J, Radoshitzky SR, Palacios G, Bavari S, Jahrling PB, Kuhn JH. Neglected filoviruses. FEMS Microbiol Rev 2016; 40:494-519. [PMID: 27268907 PMCID: PMC4931228 DOI: 10.1093/femsre/fuw010] [Citation(s) in RCA: 85] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Revised: 04/06/2016] [Accepted: 05/04/2016] [Indexed: 12/22/2022] Open
Abstract
Eight viruses are currently assigned to the family Filoviridae Marburg virus, Sudan virus and, in particular, Ebola virus have received the most attention both by researchers and the public from 1967 to 2013. During this period, natural human filovirus disease outbreaks occurred sporadically in Equatorial Africa and, despite high case-fatality rates, never included more than several dozen to a few hundred infections per outbreak. Research emphasis shifted almost exclusively to Ebola virus in 2014, when this virus was identified as the cause of an outbreak that has thus far involved more than 28 646 people and caused more than 11 323 deaths in Western Africa. Consequently, major efforts are currently underway to develop licensed medical countermeasures against Ebola virus infection. However, the ecology of and mechanisms behind Ebola virus emergence are as little understood as they are for all other filoviruses. Consequently, the possibility of the future occurrence of a large disease outbreak caused by other less characterized filoviruses (i.e. Bundibugyo virus, Lloviu virus, Ravn virus, Reston virus and Taï Forest virus) is impossible to rule out. Yet, for many of these viruses, not even rudimentary research tools are available, let alone medical countermeasures. This review summarizes the current knowledge on these less well-characterized filoviruses.
Collapse
Affiliation(s)
- Robin Burk
- Integrated Research Facility at Fort Detrick (IRF-Frederick), Division of Clinical Research (DCR), National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), B-8200 Research Plaza, Fort Detrick, Frederick, MD 21702, USA
- Department of Infectious Diseases, Virology, University of Heidelberg, 69120 Heidelberg, Baden-Württemberg, Germany
| | - Laura Bollinger
- Integrated Research Facility at Fort Detrick (IRF-Frederick), Division of Clinical Research (DCR), National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), B-8200 Research Plaza, Fort Detrick, Frederick, MD 21702, USA
| | - Joshua C. Johnson
- Integrated Research Facility at Fort Detrick (IRF-Frederick), Division of Clinical Research (DCR), National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), B-8200 Research Plaza, Fort Detrick, Frederick, MD 21702, USA
| | - Jiro Wada
- Integrated Research Facility at Fort Detrick (IRF-Frederick), Division of Clinical Research (DCR), National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), B-8200 Research Plaza, Fort Detrick, Frederick, MD 21702, USA
| | - Sheli R. Radoshitzky
- United States Army Medical Research Institute of Infectious Diseases (USAMRIID), 1425 Porter Street, Fort Detrick, Frederick, MD 21702, USA
| | - Gustavo Palacios
- United States Army Medical Research Institute of Infectious Diseases (USAMRIID), 1425 Porter Street, Fort Detrick, Frederick, MD 21702, USA
| | - Sina Bavari
- United States Army Medical Research Institute of Infectious Diseases (USAMRIID), 1425 Porter Street, Fort Detrick, Frederick, MD 21702, USA
| | - Peter B. Jahrling
- Integrated Research Facility at Fort Detrick (IRF-Frederick), Division of Clinical Research (DCR), National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), B-8200 Research Plaza, Fort Detrick, Frederick, MD 21702, USA
| | - Jens H. Kuhn
- Integrated Research Facility at Fort Detrick (IRF-Frederick), Division of Clinical Research (DCR), National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), B-8200 Research Plaza, Fort Detrick, Frederick, MD 21702, USA
| |
Collapse
|
12
|
Mekibib B, Ariën KK. Aerosol Transmission of Filoviruses. Viruses 2016; 8:v8050148. [PMID: 27223296 PMCID: PMC4885103 DOI: 10.3390/v8050148] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2015] [Revised: 05/18/2016] [Accepted: 05/20/2016] [Indexed: 12/30/2022] Open
Abstract
Filoviruses have become a worldwide public health concern because of their potential for introductions into non-endemic countries through international travel and the international transport of infected animals or animal products. Since it was first identified in 1976, in the Democratic Republic of Congo (formerly Zaire) and Sudan, the 2013–2015 western African Ebola virus disease (EVD) outbreak is the largest, both by number of cases and geographical extension, and deadliest, recorded so far in medical history. The source of ebolaviruses for human index case(s) in most outbreaks is presumptively associated with handling of bush meat or contact with fruit bats. Transmission among humans occurs easily when a person comes in contact with contaminated body fluids of patients, but our understanding of other transmission routes is still fragmentary. This review deals with the controversial issue of aerosol transmission of filoviruses.
Collapse
Affiliation(s)
- Berhanu Mekibib
- Virology Unit, Department of Biomedical Sciences, Institute of Tropical Medicine, Nationalestraat 155, Antwerp B-2000, Belgium.
- School of Veterinary Medicine, College of Natural and Computational Sciences, Hawassa University, P.O. Box 05, Hawassa, Ethiopia.
| | - Kevin K Ariën
- Virology Unit, Department of Biomedical Sciences, Institute of Tropical Medicine, Nationalestraat 155, Antwerp B-2000, Belgium.
| |
Collapse
|
13
|
Meyerholz DK. Modeling Emergent Diseases: Lessons From Middle East Respiratory Syndrome. Vet Pathol 2016; 53:517-8. [PMID: 27000399 DOI: 10.1177/0300985816634811] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- D K Meyerholz
- University of Iowa Carver College of Medicine, Iowa City, IA, USA
| |
Collapse
|
14
|
Abstract
OBJECTIVE The concept of aerosol transmission is developed to resolve limitations in conventional definitions of airborne and droplet transmission. METHODS The method was literature review. RESULTS An infectious aerosol is a collection of pathogen-laden particles in air. Aerosol particles may deposit onto or be inhaled by a susceptible person. Aerosol transmission is biologically plausible when infectious aerosols are generated by or from an infectious person, the pathogen remains viable in the environment for some period of time, and the target tissues in which the pathogen initiates infection are accessible to the aerosol. Biological plausibility of aerosol transmission is evaluated for Severe Acute Respiratory Syndrome coronavirus and norovirus and discussed for Mycobacterium tuberculosis, influenza, and Ebola virus. CONCLUSIONS Aerosol transmission reflects a modern understanding of aerosol science and allows physically appropriate explanation and intervention selection for infectious diseases.
Collapse
|
15
|
Shurtleff AC, Bavari S. Animal models for ebolavirus countermeasures discovery: what defines a useful model? Expert Opin Drug Discov 2015; 10:685-702. [PMID: 26004783 DOI: 10.1517/17460441.2015.1035252] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
INTRODUCTION Ebolaviruses are highly pathogenic filoviruses, which cause disease in humans and nonhuman primates (NHP) in Africa. The Zaire ebolavirus outbreak in 2014, which continues to greatly affect Western Africa and other countries to which the hemorrhagic fever was exported due to travel of unsymptomatic yet infected individuals, was complicated by the lack of available licensed vaccines or therapeutics to combat infection. After almost a year of research at an increased pace to find and test vaccines and therapeutics, there is now a deeper understanding of the available disease models for ebolavirus infection. Demonstration of vaccine or therapeutic efficacy in NHP models of ebolavirus infection is crucial to the development and eventual licensure of ebolavirus medical countermeasures, so that safe and effective countermeasures can be accelerated into human clinical trials. AREAS COVERED The authors describe ebolavirus hemorrhagic fever (EHF) disease in various animal species: mice, guinea pigs, hamsters, pigs and NHP, to include baboons, marmosets, rhesus and cynomolgus macaques, as well as African green monkeys. Because the NHP models are supremely useful for therapeutics and vaccine testing, emphasis is placed on comparison of these models, and their use as gold-standard models of EHF. EXPERT OPINION Animal models of EHF varying from rodents to NHP species are currently under evaluation for their reproducibility and utility for modeling infection in humans. Complete development and licensure of therapeutic agents and vaccines will require demonstration that mechanisms conferring protection in NHP models of infection are predictive of protective responses in humans, for a given countermeasure.
Collapse
Affiliation(s)
- Amy C Shurtleff
- U.S. Army Medical Research Institute of Infectious Diseases, Fort Detrick, Division of Molecular and Translational Sciences , 1425 Porter Street, Frederick, MD 21702 , USA +1 301 619 4246 ; +1 541 754 3545 ;
| | | |
Collapse
|
16
|
Osterholm MT, Moore KA, Kelley NS, Brosseau LM, Wong G, Murphy FA, Peters CJ, LeDuc JW, Russell PK, Van Herp M, Kapetshi J, Muyembe JJT, Ilunga BK, Strong JE, Grolla A, Wolz A, Kargbo B, Kargbo DK, Sanders DA, Kobinger GP. Transmission of Ebola viruses: what we know and what we do not know. mBio 2015; 6:e00137. [PMID: 25698835 PMCID: PMC4358015 DOI: 10.1128/mbio.00137-15] [Citation(s) in RCA: 119] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Available evidence demonstrates that direct patient contact and contact with infectious body fluids are the primary modes for Ebola virus transmission, but this is based on a limited number of studies. Key areas requiring further study include (i) the role of aerosol transmission (either via large droplets or small particles in the vicinity of source patients), (ii) the role of environmental contamination and fomite transmission, (iii) the degree to which minimally or mildly ill persons transmit infection, (iv) how long clinically relevant infectiousness persists, (v) the role that "superspreading events" may play in driving transmission dynamics, (vi) whether strain differences or repeated serial passage in outbreak settings can impact virus transmission, and (vii) what role sylvatic or domestic animals could play in outbreak propagation, particularly during major epidemics such as the 2013-2015 West Africa situation. In this review, we address what we know and what we do not know about Ebola virus transmission. We also hypothesize that Ebola viruses have the potential to be respiratory pathogens with primary respiratory spread.
Collapse
Affiliation(s)
- Michael T Osterholm
- Center for Infectious Disease Research and Policy, University of Minnesota, Minneapolis, Minnesota, USA
| | - Kristine A Moore
- Center for Infectious Disease Research and Policy, University of Minnesota, Minneapolis, Minnesota, USA
| | - Nicholas S Kelley
- Center for Infectious Disease Research and Policy, University of Minnesota, Minneapolis, Minnesota, USA
| | - Lisa M Brosseau
- Division of Environmental and Occupational Health Sciences, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Gary Wong
- National Laboratory for Zoonotic Diseases and Special Pathogens, Public Health Agency of Canada, Winnipeg, Canada
| | - Frederick A Murphy
- The Galveston National Laboratory, University of Texas Medical Branch, Galveston, Texas, USA
| | - Clarence J Peters
- The Galveston National Laboratory, University of Texas Medical Branch, Galveston, Texas, USA
| | - James W LeDuc
- The Galveston National Laboratory, University of Texas Medical Branch, Galveston, Texas, USA
| | | | - Michel Van Herp
- Medical Department Unit, Médecins sans Frontières, Brussels, Belgium
| | - Jimmy Kapetshi
- Institut National de Recherche Biomédicale, Kinshasa, Democratic Republic of the Congo
| | | | | | - James E Strong
- National Laboratory for Zoonotic Diseases and Special Pathogens, Public Health Agency of Canada, Winnipeg, Canada
| | - Allen Grolla
- National Laboratory for Zoonotic Diseases and Special Pathogens, Public Health Agency of Canada, Winnipeg, Canada
| | - Anja Wolz
- Medical Department Unit, Médecins sans Frontières, Brussels, Belgium
| | - Brima Kargbo
- Ministry of Health and Sanitation, Freetown, Sierra Leone
| | - David K Kargbo
- Ministry of Health and Sanitation, Freetown, Sierra Leone
| | - David Avram Sanders
- Department of Biological Sciences, Purdue University, Lafayette, Indiana, USA
| | - Gary P Kobinger
- National Laboratory for Zoonotic Diseases and Special Pathogens, Public Health Agency of Canada, Winnipeg, Canada
| |
Collapse
|
17
|
Wong G, Richardson JS, Cutts T, Qiu X, Kobinger GP. Intranasal immunization with an adenovirus vaccine protects guinea pigs from Ebola virus transmission by infected animals. Antiviral Res 2015; 116:17-9. [PMID: 25596432 DOI: 10.1016/j.antiviral.2015.01.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2014] [Revised: 01/04/2015] [Accepted: 01/06/2015] [Indexed: 10/24/2022]
Abstract
Experimental Ebola virus (EBOV) vaccines have previously been shown to protect animals against a high dose intramuscular (IM) challenge, which is seen as a stringent challenge model. However, the protective efficacy against other modes of infection, such as contact with infectious hosts, is unknown. Using a previously established EBOV transmission animal model, we evaluated the efficacy of an adenovirus-based EBOV vaccine given to guinea pigs (gps) 4weeks before direct contact with untreated, infectious animals. Prior vaccination resulted in robust levels of EBOV-specific antibodies and conferred complete protection in gps. These results support the use of vaccines to prevent EBOV transmission between hosts.
Collapse
Affiliation(s)
- Gary Wong
- Special Pathogens Program, National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, MB, Canada; Department of Medical Microbiology, University of Manitoba, Winnipeg, MB, Canada
| | - Jason S Richardson
- Special Pathogens Program, National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, MB, Canada
| | - Todd Cutts
- Special Pathogens Program, National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, MB, Canada
| | - Xiangguo Qiu
- Special Pathogens Program, National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, MB, Canada
| | - Gary P Kobinger
- Special Pathogens Program, National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, MB, Canada; Department of Medical Microbiology, University of Manitoba, Winnipeg, MB, Canada; Department of Immunology, University of Manitoba, Winnipeg, MB, Canada; Department of Pathology and Laboratory Medicine, University of Pennsylvania School of Medicine, Philadelphia, PA, USA.
| |
Collapse
|
18
|
Abstract
UNLABELLED Ebola virus (EBOV) transmission is currently poorly characterized and is thought to occur primarily by direct contact with infectious material; however transmission from swine to nonhuman primates via the respiratory tract has been documented. To establish an EBOV transmission model for performing studies with statistical significance, groups of six guinea pigs (gps) were challenged intranasally (i.n.) or intraperitoneally (i.p.) with 10,000 times the 50% lethal dose (LD50) of gp-adapted EBOV, and naive gps were then introduced as cage mates for contact exposure at 1 day postinfection (p.i.). The animals were monitored for survival and clinical signs of disease and quantitated for virus shedding postexposure. Changes in the duration of contact of naive gps with infected animals were evaluated for their impact on transmission efficiency. Transmission was more efficient from i.n.- than from i.p.-challenged gps, with 17% versus 83% of naive gps surviving exposure, respectively. Virus shedding was detected beginning at 3 days p.i. from both i.n.- and i.p.-challenged animals. Contact duration positively correlated with transmission efficiency, and the abrogation of direct contact between infected and naive animals through the erection of a steel mesh was effective at stopping virus spread, provided that infectious animal bedding was absent from the cages. Histopathological and immunohistochemical findings show that i.n.-infected gps display enhanced lung pathology and EBOV antigen in the trachea, which supports increased virus transmission from these animals. The results suggest that i.n.-challenged gps are more infectious to naive animals than their systemically infected counterparts and that transmission occurs through direct contact with infectious materials, including those transported through air movement over short distances. IMPORTANCE Ebola is generally thought to be spread between humans though infectious bodily fluids. However, a study has shown that Ebola can be spread from pigs to monkeys without direct contact. Further studies have been hampered, because an economical animal model for Ebola transmission is not available. To address this, we established a transmission model in guinea pigs and determined the mechanisms behind virus spread. The survival data, in addition to microscopic examination of lung and trachea sections, show that mucosal infection of guinea pigs is an efficient model for Ebola transmission. Virus spread is increased with longer contact times with an infected animal and is possible without direct contact between an infected and a naive host but can be stopped if infectious materials are absent. These results warrant consideration for the development of future strategies against Ebola transmission and for a better understanding of the parameters involved in virus spread.
Collapse
|
19
|
Zumbrun EE. Mission critical: mobilization of essential animal models for Ebola, Nipah, and Machupo virus infections. Vet Pathol 2014; 52:18-20. [PMID: 25352204 DOI: 10.1177/0300985814556781] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The reports for Ebola virus Zaire (EBOV), Nipah virus, and Machupo virus (MACV) pathogenesis, in this issue of Veterinary Pathology, are timely considering recent events, both nationally and internationally. EBOV, Nipah virus, and MACV cause highly lethal infections for which no Food and Drug Administration (FDA) licensed vaccines or therapies exist. Not only are there concerns that these agents could be used by those with malicious intent, but shifts in ecological distribution of viral reservoirs due to climate change or globalization could lead to more frequent infections within remote regions than previously seen as well as outbreaks in more populous areas. The current EBOV epidemic shows no sign of abating across 3 West African nations (as of October 2014), including densely populated areas, far outpacing infection rates of previous outbreaks. A limited number of cases have also arisen in the United States and Europe. With few treatment options for these deadly viruses, development of animal models reflective of human disease is paramount to combat these diseases. As an example of this potential, a new treatment compound, ZMapp, that had demonstrated efficacy against EBOV infection in nonhuman primates (NHPs) received an emergency compassionate use exception from the FDA for the treatment of 2 American medical workers infected with EBOV, and they are currently virus free and recovering.
Collapse
Affiliation(s)
- E E Zumbrun
- Department of Pathology, Microbiology and Immunology, University of South Carolina School of Medicine, Columbia, SC, USA
| |
Collapse
|