1
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Groger M, Ramharter M. Rapid diagnostic tests for Lassa fever: what do we aim for? THE LANCET. INFECTIOUS DISEASES 2024:S1473-3099(24)00235-4. [PMID: 38734013 DOI: 10.1016/s1473-3099(24)00235-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2024] [Accepted: 04/08/2024] [Indexed: 05/13/2024]
Affiliation(s)
- Mirjam Groger
- Centre of Tropical Medicine, Bernhard Nocht Institute for Tropical Medicine, and Department of Internal Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
| | - Michael Ramharter
- Centre of Tropical Medicine, Bernhard Nocht Institute for Tropical Medicine, and Department of Internal Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
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2
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Nunberg JH, Westover JB, York J, Jung KH, Bailey KW, Boardman KM, Li M, Furnell RS, Wasson SR, Murray JS, Kaundal R, Thomas AJ, Gowen BB. Restoration of virulence in the attenuated Candid#1 vaccine virus requires reversion at both positions 168 and 427 in the envelope glycoprotein GPC. J Virol 2024; 98:e0011224. [PMID: 38506509 PMCID: PMC11019782 DOI: 10.1128/jvi.00112-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2024] [Accepted: 02/29/2024] [Indexed: 03/21/2024] Open
Abstract
Live-attenuated virus vaccines provide long-lived protection against viral disease but carry inherent risks of residual pathogenicity and genetic reversion. The live-attenuated Candid#1 vaccine was developed to protect Argentines against lethal infection by the Argentine hemorrhagic fever arenavirus, Junín virus. Despite its safety and efficacy in Phase III clinical study, the vaccine is not licensed in the US, in part due to concerns regarding the genetic stability of attenuation. Previous studies had identified a single F427I mutation in the transmembrane domain of the Candid#1 envelope glycoprotein GPC as the key determinant of attenuation, as well as the propensity of this mutation to revert upon passage in cell culture and neonatal mice. To ascertain the consequences of this reversion event, we introduced the I427F mutation into recombinant Candid#1 (I427F rCan) and investigated the effects in two validated small-animal models: in mice expressing the essential virus receptor (human transferrin receptor 1; huTfR1) and in the conventional guinea pig model. We report that I427F rCan displays only modest virulence in huTfR1 mice and appears attenuated in guinea pigs. Reversion at another attenuating locus in Candid#1 GPC (T168A) was also examined, and a similar pattern was observed. By contrast, virus bearing both revertant mutations (A168T+I427F rCan) approached the lethal virulence of the pathogenic Romero strain in huTfR1 mice. Virulence was less extreme in guinea pigs. Our findings suggest that genetic stabilization at both positions is required to minimize the likelihood of reversion to virulence in a second-generation Candid#1 vaccine.IMPORTANCELive-attenuated virus vaccines, such as measles/mumps/rubella and oral poliovirus, provide robust protection against disease but carry with them the risk of genetic reversion to the virulent form. Here, we analyze the genetics of reversion in the live-attenuated Candid#1 vaccine that is used to protect against Argentine hemorrhagic fever, an often-lethal disease caused by the Junín arenavirus. In two validated small-animal models, we find that restoration of virulence in recombinant Candid#1 viruses requires back-mutation at two positions specific to the Candid#1 envelope glycoprotein GPC, at positions 168 and 427. Viruses bearing only a single change showed only modest virulence. We discuss strategies to genetically harden Candid#1 GPC against these two reversion events in order to develop a safer second-generation Candid#1 vaccine virus.
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Affiliation(s)
- Jack H. Nunberg
- Montana Biotechnology Center, University of Montana, Missoula, Montana, USA
| | - Jonna B. Westover
- Department of Animal Dairy and Veterinary Sciences, Utah State University, Logan, Utah, USA
- Institute for Antiviral Research, Utah State University, Logan, Utah, USA
| | - Joanne York
- Montana Biotechnology Center, University of Montana, Missoula, Montana, USA
| | - Kie Hoon Jung
- Department of Animal Dairy and Veterinary Sciences, Utah State University, Logan, Utah, USA
- Institute for Antiviral Research, Utah State University, Logan, Utah, USA
| | - Kevin W. Bailey
- Department of Animal Dairy and Veterinary Sciences, Utah State University, Logan, Utah, USA
- Institute for Antiviral Research, Utah State University, Logan, Utah, USA
| | - Kirsten M. Boardman
- Department of Animal Dairy and Veterinary Sciences, Utah State University, Logan, Utah, USA
- Institute for Antiviral Research, Utah State University, Logan, Utah, USA
| | - Minghao Li
- Department of Animal Dairy and Veterinary Sciences, Utah State University, Logan, Utah, USA
- Institute for Antiviral Research, Utah State University, Logan, Utah, USA
| | - Rachel S. Furnell
- Department of Animal Dairy and Veterinary Sciences, Utah State University, Logan, Utah, USA
- Institute for Antiviral Research, Utah State University, Logan, Utah, USA
| | - Samantha R. Wasson
- Department of Animal Dairy and Veterinary Sciences, Utah State University, Logan, Utah, USA
- Institute for Antiviral Research, Utah State University, Logan, Utah, USA
| | - Justin S. Murray
- Department of Animal Dairy and Veterinary Sciences, Utah State University, Logan, Utah, USA
- Institute for Antiviral Research, Utah State University, Logan, Utah, USA
| | - Rakesh Kaundal
- Department of Plants, Soils, and Climate, Utah State University, Logan, Utah, USA
- Center for Integrated BioSystems, Utah State University, Logan, Utah, USA
| | - Aaron J. Thomas
- Department of Animal Dairy and Veterinary Sciences, Utah State University, Logan, Utah, USA
- Center for Integrated BioSystems, Utah State University, Logan, Utah, USA
| | - Brian B. Gowen
- Department of Animal Dairy and Veterinary Sciences, Utah State University, Logan, Utah, USA
- Institute for Antiviral Research, Utah State University, Logan, Utah, USA
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3
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Reyna RA, Littlefield KE, Shehu N, Makishima T, Maruyama J, Paessler S. The Importance of Lassa Fever and Its Disease Management in West Africa. Viruses 2024; 16:266. [PMID: 38400041 PMCID: PMC10892767 DOI: 10.3390/v16020266] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2023] [Revised: 01/21/2024] [Accepted: 02/02/2024] [Indexed: 02/25/2024] Open
Abstract
Lassa virus (LASV) is a zoonotic pathogen endemic throughout western Africa and is responsible for a human disease known as Lassa fever (LF). Historically, LASV has been emphasized as one of the greatest public health threats in West Africa, with up to 300,000 cases and 5000 associated deaths per year. This, and the fact that the disease has been reported in travelers, has driven a rapid production of various vaccine candidates. Several of these vaccines are currently in clinical development, despite limitations in understanding the immune response to infection. Alarmingly, the host immune response has been implicated in the induction of sensorineural hearing loss in LF survivors, legitimately raising safety questions about any future vaccines as well as efficacy in preventing potential hearing loss. The objective of this article is to revisit the importance and prevalence of LF in West Africa, with focus on Nigeria, and discuss current therapeutic approaches and ongoing vaccine development. In addition, we aim to emphasize the need for more scientific studies relating to LF-associated hearing loss, and to promote critical discussion about potential risks and benefits of vaccinating the population in endemic regions of West Africa.
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Affiliation(s)
- Rachel A. Reyna
- Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555, USA
| | - Kirsten E. Littlefield
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX 77555, USA
| | - Nathan Shehu
- Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555, USA
- Infectious Disease Unit, Department of Medicine, Jos University Teaching Hospital, Jos P.M.B. 2076, Nigeria
| | - Tomoko Makishima
- Department of Otolaryngology, University of Texas Medical Branch, Galveston, TX 77555, USA
| | - Junki Maruyama
- Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555, USA
| | - Slobodan Paessler
- Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555, USA
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX 77555, USA
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4
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Brouwer PJ, Perrett HR, Beaumont T, Nijhuis H, Kruijer S, Burger JA, Lee WH, Müller-Kraüter H, Sanders RW, Strecker T, van Gils MJ, Ward AB. Defining bottlenecks and opportunities for Lassa virus neutralization by structural profiling of vaccine-induced polyclonal antibody responses. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.12.21.572918. [PMID: 38187682 PMCID: PMC10769344 DOI: 10.1101/2023.12.21.572918] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2024]
Abstract
Lassa fever continues to be a major public health burden in endemic countries in West Africa, yet effective therapies or vaccines are lacking. The isolation of potent and protective neutralizing antibodies against the Lassa virus glycoprotein complex (GPC) justifies the development of vaccines that can elicit strong neutralizing antibody responses. However, Lassa vaccines candidates have generally been unsuccessful in doing so and the associated antibody responses to these vaccines remain poorly characterized. Here, we establish an electron-microscopy based epitope mapping pipeline that enables high-resolution structural characterization of polyclonal antibodies to GPC. By applying this method to rabbits vaccinated with a recombinant GPC vaccine and a GPC-derived virus-like particle, we reveal determinants of neutralization which involve epitopes of the GPC-C, GPC-A, and GP1-A competition clusters. Furthermore, by identifying previously undescribed immunogenic off-target epitopes, we expose challenges that recombinant GPC vaccines face. By enabling detailed polyclonal antibody characterization, our work ushers in a next generation of more rational Lassa vaccine design.
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Affiliation(s)
- Philip J.M. Brouwer
- Department of Integrative Structural and Computational Biology, Scripps Research, La Jolla, CA 92037, USA
| | - Hailee R. Perrett
- Department of Integrative Structural and Computational Biology, Scripps Research, La Jolla, CA 92037, USA
| | - Tim Beaumont
- Department of Medical Microbiology and Infection Prevention, Amsterdam University Medical Center, Location AMC, University of Amsterdam, Amsterdam Infection & Immunity Institute, Amsterdam 1105 AZ, the Netherlands
| | - Haye Nijhuis
- Department of Medical Microbiology and Infection Prevention, Amsterdam University Medical Center, Location AMC, University of Amsterdam, Amsterdam Infection & Immunity Institute, Amsterdam 1105 AZ, the Netherlands
| | - Sabine Kruijer
- Department of Medical Microbiology and Infection Prevention, Amsterdam University Medical Center, Location AMC, University of Amsterdam, Amsterdam Infection & Immunity Institute, Amsterdam 1105 AZ, the Netherlands
| | - Judith A. Burger
- Department of Medical Microbiology and Infection Prevention, Amsterdam University Medical Center, Location AMC, University of Amsterdam, Amsterdam Infection & Immunity Institute, Amsterdam 1105 AZ, the Netherlands
| | - Wen-Hsin Lee
- Department of Integrative Structural and Computational Biology, Scripps Research, La Jolla, CA 92037, USA
| | | | - Rogier W. Sanders
- Department of Medical Microbiology and Infection Prevention, Amsterdam University Medical Center, Location AMC, University of Amsterdam, Amsterdam Infection & Immunity Institute, Amsterdam 1105 AZ, the Netherlands
- Department of Microbiology and Immunology, Weill Medical College of Cornell University, New York, NY 10021, USA
| | - Thomas Strecker
- Institute of Virology, Philipps University Marburg, 35043 Marburg, Germany
| | - Marit J. van Gils
- Department of Medical Microbiology and Infection Prevention, Amsterdam University Medical Center, Location AMC, University of Amsterdam, Amsterdam Infection & Immunity Institute, Amsterdam 1105 AZ, the Netherlands
| | - Andrew B. Ward
- Department of Integrative Structural and Computational Biology, Scripps Research, La Jolla, CA 92037, USA
- Lead contact
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5
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Blacksell SD, Dhawan S, Kusumoto M, Le KK, Summermatter K, O'Keefe J, Kozlovac J, Almuhairi SS, Sendow I, Scheel CM, Ahumibe A, Masuku ZM, Bennett AM, Kojima K, Harper DR, Hamilton K. The Biosafety Research Road Map: The Search for Evidence to Support Practices in the Laboratory-Crimean Congo Haemorrhagic Fever Virus and Lassa Virus. APPLIED BIOSAFETY 2023; 28:216-229. [PMID: 38090357 PMCID: PMC10712363 DOI: 10.1089/apb.2022.0044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2024]
Abstract
Introduction Crimean Congo Hemorrhagic Fever (CCHF) virus and Lassa virus (LASV) are zoonotic agents regarded as high-consequence pathogens due to their high case fatality rates. CCHF virus is a vector-borne disease and is transmitted by tick bites. Lassa virus is spread via aerosolization of dried rat urine, ingesting infected rats, and direct contact with or consuming food and water contaminated with rat excreta. Methods The scientific literature for biosafety practices has been reviewed for both these two agents to assess the evidence base and biosafety-related knowledge gaps. The review focused on five main areas, including the route of inoculation/modes of transmission, infectious dose, laboratory-acquired infections, containment releases, and disinfection and decontamination strategies. Results There is a lack of data on the safe collection and handling procedures for tick specimens and the infectious dose from an infective tick bite for CCHF investigations. In addition, there are gaps in knowledge about gastrointestinal and contact infectious doses for Lassa virus, sample handling and transport procedures outside of infectious disease areas, and the contribution of asymptomatic carriers in viral circulation. Conclusion Due to the additional laboratory hazards posed by these two agents, the authors recommend developing protocols that work effectively and safely in highly specialized laboratories in non-endemic regions and a laboratory with limited resources in endemic areas.
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Affiliation(s)
- Stuart D. Blacksell
- Mahidol-Oxford Tropical Research Medicine Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, Nuffield Department of Medicine Research Building, University of Oxford, Oxford, United Kingdom
| | - Sandhya Dhawan
- Mahidol-Oxford Tropical Research Medicine Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Marina Kusumoto
- Mahidol-Oxford Tropical Research Medicine Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Kim Khanh Le
- Mahidol-Oxford Tropical Research Medicine Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | | | - Joseph O'Keefe
- Ministry for Primary Industries, Wellington, New Zealand
| | - Joseph Kozlovac
- U.S. Department of Agriculture, Agricultural Research Service, Beltsville, Maryland, USA
| | | | - Indrawati Sendow
- Research Center for Veterinary Science, National Research and Innovation Agency, Indonesia
| | - Christina M. Scheel
- WHO Collaborating Center for Biosafety and Biosecurity, Office of the Associate Director for Laboratory Science, Center for Global Health, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| | - Anthony Ahumibe
- Nigeria Centre for Disease Control, Abuja and Prevention, Nigeria
| | - Zibusiso M. Masuku
- National Institute for Communicable Diseases of the National Health Laboratory Services, Sandringham, South Africa
| | | | - Kazunobu Kojima
- Department of Epidemic and Pandemic Preparedness and Prevention, World Health Organization, Geneva, Switzerland
| | - David R. Harper
- The Royal Institute of International Affairs, London, United Kingdom
| | - Keith Hamilton
- World Organisation for Animal Health (OIE), Paris, France
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6
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Schreiner CL, Basinski AJ, Remien CH, Nuismer SL. Optimizing the delivery of self-disseminating vaccines in fluctuating wildlife populations. PLoS Negl Trop Dis 2023; 17:e0011018. [PMID: 37594985 PMCID: PMC10468088 DOI: 10.1371/journal.pntd.0011018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Revised: 08/30/2023] [Accepted: 07/30/2023] [Indexed: 08/20/2023] Open
Abstract
Zoonotic pathogens spread by wildlife continue to spill into human populations and threaten human lives. A potential way to reduce this threat is by vaccinating wildlife species that harbor pathogens that are infectious to humans. Unfortunately, even in cases where vaccines can be distributed en masse as edible baits, achieving levels of vaccine coverage sufficient for pathogen elimination is rare. Developing vaccines that self-disseminate may help solve this problem by magnifying the impact of limited direct vaccination. Although models exist that quantify how well these self-disseminating vaccines will work when introduced into temporally stable wildlife populations, how well they will perform when introduced into populations with pronounced seasonal population dynamics remains unknown. Here we develop and analyze mathematical models of fluctuating wildlife populations that allow us to study how reservoir ecology, vaccine design, and vaccine delivery interact to influence vaccine coverage and opportunities for pathogen elimination. Our results demonstrate that the timing of vaccine delivery can make or break the success of vaccination programs. As a general rule, the effectiveness of self-disseminating vaccines is optimized by introducing after the peak of seasonal reproduction when the number of susceptible animals is near its maximum.
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Affiliation(s)
- Courtney L. Schreiner
- Department of Ecology and Evolutionary Biology, University of Tennessee, Knoxville, Tennessee, United States of America
| | - Andrew J. Basinski
- Institute for Interdisciplinary Data Sciences, University of Idaho, Moscow, Idaho, United States of America
| | - Christopher H. Remien
- Department of Mathematics and Statistical Sciences, University of Idaho, Moscow, Idaho, United States of America
| | - Scott L. Nuismer
- Department of Biological Sciences, University of Idaho, Moscow, Idaho, United States of America
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7
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Perrett HR, Brouwer PJM, Hurtado J, Newby ML, Liu L, Müller-Kräuter H, Müller Aguirre S, Burger JA, Bouhuijs JH, Gibson G, Messmer T, Schieffelin JS, Antanasijevic A, Boons GJ, Strecker T, Crispin M, Sanders RW, Briney B, Ward AB. Structural conservation of Lassa virus glycoproteins and recognition by neutralizing antibodies. Cell Rep 2023; 42:112524. [PMID: 37209096 PMCID: PMC10242449 DOI: 10.1016/j.celrep.2023.112524] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2022] [Revised: 03/07/2023] [Accepted: 05/01/2023] [Indexed: 05/22/2023] Open
Abstract
Lassa fever is an acute hemorrhagic fever caused by the zoonotic Lassa virus (LASV). The LASV glycoprotein complex (GPC) mediates viral entry and is the sole target for neutralizing antibodies. Immunogen design is complicated by the metastable nature of recombinant GPCs and the antigenic differences among phylogenetically distinct LASV lineages. Despite the sequence diversity of the GPC, structures of most lineages are lacking. We present the development and characterization of prefusion-stabilized, trimeric GPCs of LASV lineages II, V, and VII, revealing structural conservation despite sequence diversity. High-resolution structures and biophysical characterization of the GPC in complex with GP1-A-specific antibodies suggest their neutralization mechanisms. Finally, we present the isolation and characterization of a trimer-preferring neutralizing antibody belonging to the GPC-B competition group with an epitope that spans adjacent protomers and includes the fusion peptide. Our work provides molecular detail information on LASV antigenic diversity and will guide efforts to design pan-LASV vaccines.
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Affiliation(s)
- Hailee R Perrett
- Department of Integrative, Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Philip J M Brouwer
- Department of Integrative, Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Jonathan Hurtado
- Department of Immunology and Microbiology, Scripps Research, La Jolla, CA 92037, USA; Center for Viral Systems Biology, Scripps Research, La Jolla, CA 92037, USA
| | - Maddy L Newby
- School of Biological Sciences, University of Southampton, Southampton SO17 1BJ, UK
| | - Lin Liu
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA 30602, USA
| | | | | | - Judith A Burger
- Department of Medical Microbiology and Infection Prevention, Amsterdam University Medical Centers. Location AMC, University of Amsterdam, Amsterdam Infection & Immunity Institute, Amsterdam 1105 AZ, the Netherlands
| | - Joey H Bouhuijs
- Department of Medical Microbiology and Infection Prevention, Amsterdam University Medical Centers. Location AMC, University of Amsterdam, Amsterdam Infection & Immunity Institute, Amsterdam 1105 AZ, the Netherlands
| | - Grace Gibson
- Department of Integrative, Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Terrence Messmer
- Department of Immunology and Microbiology, Scripps Research, La Jolla, CA 92037, USA
| | - John S Schieffelin
- Department of Pediatrics, Tulane University School of Medicine, New Orleans, LA 70112, USA
| | - Aleksandar Antanasijevic
- Department of Integrative, Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Geert-Jan Boons
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA 30602, USA; Department of Chemical Biology and Drug Discovery, Utrecht University, Utrecht 3584 CG, the Netherlands
| | - Thomas Strecker
- Institute of Virology, Philipps University Marburg, 35043 Marburg, Germany
| | - Max Crispin
- School of Biological Sciences, University of Southampton, Southampton SO17 1BJ, UK
| | - Rogier W Sanders
- Department of Medical Microbiology and Infection Prevention, Amsterdam University Medical Centers. Location AMC, University of Amsterdam, Amsterdam Infection & Immunity Institute, Amsterdam 1105 AZ, the Netherlands; Department of Microbiology and Immunology, Weill Medical College of Cornell University, New York, NY 10021, USA
| | - Bryan Briney
- Department of Immunology and Microbiology, Scripps Research, La Jolla, CA 92037, USA; Center for Viral Systems Biology, Scripps Research, La Jolla, CA 92037, USA
| | - Andrew B Ward
- Department of Integrative, Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA 92037, USA.
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8
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Okokhere PO. Finding a safe and effective vaccine for the Lassa virus. Lancet 2023; 401:1242-1243. [PMID: 36934735 DOI: 10.1016/s0140-6736(23)00093-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Accepted: 01/10/2023] [Indexed: 03/18/2023]
Affiliation(s)
- Peter O Okokhere
- Department of Medicine, Irrua Specialist Teaching Hospital, Irrua, Nigeria; Department of Medicine, Faculty of Clinical Sciences, Ambrose Alli University, Ekpoma 310103, Nigeria.
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9
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Bourner J, Salam AP, Jaspard M, Olayinka A, Fritzell C, Goncalves B, Vaillant M, Edwards T, Erameh C, Ajayi N, Ramharter M, Olliaro P. The West Africa Lassa fever Consortium pre-positioned protocol for a Phase II/III adaptive, randomised, controlled, platform trial to evaluate multiple Lassa fever therapeutics. Wellcome Open Res 2023. [DOI: 10.12688/wellcomeopenres.19041.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/18/2023] Open
Abstract
Background: This is a standardized, pre-positioned protocol for the coordinated evaluation of Lassa fever therapeutics. The protocol is the product of discussions that took place in 2021 and 2022 among international investigators from a wide range of scientific and medical disciplines working together within the West Africa Lassa fever Consortium (WALC). Methods: This is a clinical Phase II/III multicentre randomised controlled platform trial using a superiority framework with an equal allocation ratio and a composite primary endpoint of all-cause mortality OR new onset of i) acute kidney failure (AKF), OR ii) acute respiratory failure (ARF), OR iii) shock assessed from enrolment (D0) to D28. Discussion: This pre-positioned protocol was developed by the WALC and made available for adaptation and implementation by the wider Lassa fever research community in order to generate efficient, reliable, and comparable evidence for Lassa fever therapeutics.
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10
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Mateo M, Reynard S, Pietrosemoli N, Perthame E, Journeaux A, Noy K, Germain C, Carnec X, Picard C, Borges-Cardoso V, Hortion J, Lopez-Maestre H, Regnard P, Fellmann L, Vallve A, Barron S, Jourjon O, Lacroix O, Duthey A, Dirheimer M, Daniau M, Legras-Lachuer C, Carbonnelle C, Raoul H, Tangy F, Baize S. Rapid protection induced by a single-shot Lassa vaccine in male cynomolgus monkeys. Nat Commun 2023; 14:1352. [PMID: 36906645 PMCID: PMC10008018 DOI: 10.1038/s41467-023-37050-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Accepted: 02/22/2023] [Indexed: 03/13/2023] Open
Abstract
Lassa fever hits West African countries annually in the absence of licensed vaccine to limit the burden of this viral hemorrhagic fever. We previously developed MeV-NP, a single-shot vaccine protecting cynomolgus monkeys against divergent strains one month or more than a year before Lassa virus infection. Given the limited dissemination area during outbreaks and the risk of nosocomial transmission, a vaccine inducing rapid protection could be useful to protect exposed people during outbreaks in the absence of preventive vaccination. Here, we test whether the time to protection can be reduced after immunization by challenging measles virus pre-immune male cynomolgus monkeys sixteen or eight days after a single shot of MeV-NP. None of the immunized monkeys develop disease and they rapidly control viral replication. Animals immunized eight days before the challenge are the best controllers, producing a strong CD8 T-cell response against the viral glycoprotein. A group of animals was also vaccinated one hour after the challenge, but was not protected and succumbed to the disease as the control animals. This study demonstrates that MeV-NP can induce a rapid protective immune response against Lassa fever in the presence of MeV pre-existing immunity but can likely not be used as therapeutic vaccine.
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Affiliation(s)
- Mathieu Mateo
- Unité de Biologie des Infections Virales Emergentes, Institut Pasteur, 69007, Lyon, France.,Centre International de Recherche en Infectiologie (CIRI), Université de Lyon, INSERM U1111, Ecole Normale Supérieure de Lyon, Université Lyon 1, CNRS UMR5308, 69007, Lyon, France
| | - Stéphanie Reynard
- Unité de Biologie des Infections Virales Emergentes, Institut Pasteur, 69007, Lyon, France.,Centre International de Recherche en Infectiologie (CIRI), Université de Lyon, INSERM U1111, Ecole Normale Supérieure de Lyon, Université Lyon 1, CNRS UMR5308, 69007, Lyon, France
| | - Natalia Pietrosemoli
- Institut Pasteur, Université Paris Cité, Bioinformatics and Biostatistics Hub, Paris, France
| | - Emeline Perthame
- Institut Pasteur, Université Paris Cité, Bioinformatics and Biostatistics Hub, Paris, France
| | - Alexandra Journeaux
- Unité de Biologie des Infections Virales Emergentes, Institut Pasteur, 69007, Lyon, France.,Centre International de Recherche en Infectiologie (CIRI), Université de Lyon, INSERM U1111, Ecole Normale Supérieure de Lyon, Université Lyon 1, CNRS UMR5308, 69007, Lyon, France
| | - Kodie Noy
- Unité de Biologie des Infections Virales Emergentes, Institut Pasteur, 69007, Lyon, France.,Centre International de Recherche en Infectiologie (CIRI), Université de Lyon, INSERM U1111, Ecole Normale Supérieure de Lyon, Université Lyon 1, CNRS UMR5308, 69007, Lyon, France
| | - Clara Germain
- Unité de Biologie des Infections Virales Emergentes, Institut Pasteur, 69007, Lyon, France.,Centre International de Recherche en Infectiologie (CIRI), Université de Lyon, INSERM U1111, Ecole Normale Supérieure de Lyon, Université Lyon 1, CNRS UMR5308, 69007, Lyon, France
| | - Xavier Carnec
- Unité de Biologie des Infections Virales Emergentes, Institut Pasteur, 69007, Lyon, France.,Centre International de Recherche en Infectiologie (CIRI), Université de Lyon, INSERM U1111, Ecole Normale Supérieure de Lyon, Université Lyon 1, CNRS UMR5308, 69007, Lyon, France
| | - Caroline Picard
- Unité de Biologie des Infections Virales Emergentes, Institut Pasteur, 69007, Lyon, France.,Centre International de Recherche en Infectiologie (CIRI), Université de Lyon, INSERM U1111, Ecole Normale Supérieure de Lyon, Université Lyon 1, CNRS UMR5308, 69007, Lyon, France
| | - Virginie Borges-Cardoso
- Unité de Biologie des Infections Virales Emergentes, Institut Pasteur, 69007, Lyon, France.,Centre International de Recherche en Infectiologie (CIRI), Université de Lyon, INSERM U1111, Ecole Normale Supérieure de Lyon, Université Lyon 1, CNRS UMR5308, 69007, Lyon, France
| | - Jimmy Hortion
- Unité de Biologie des Infections Virales Emergentes, Institut Pasteur, 69007, Lyon, France.,Centre International de Recherche en Infectiologie (CIRI), Université de Lyon, INSERM U1111, Ecole Normale Supérieure de Lyon, Université Lyon 1, CNRS UMR5308, 69007, Lyon, France
| | - Hélène Lopez-Maestre
- Institut Pasteur, Université Paris Cité, Bioinformatics and Biostatistics Hub, Paris, France
| | - Pierrick Regnard
- SILABE, Université de Strasbourg, fort Foch, Niederhausbergen, France
| | - Lyne Fellmann
- SILABE, Université de Strasbourg, fort Foch, Niederhausbergen, France
| | - Audrey Vallve
- Laboratoire P4 INSERM - Jean Mérieux, INSERM US003, 69007, Lyon, France
| | - Stéphane Barron
- Laboratoire P4 INSERM - Jean Mérieux, INSERM US003, 69007, Lyon, France
| | - Ophélie Jourjon
- Laboratoire P4 INSERM - Jean Mérieux, INSERM US003, 69007, Lyon, France
| | - Orianne Lacroix
- Laboratoire P4 INSERM - Jean Mérieux, INSERM US003, 69007, Lyon, France
| | - Aurélie Duthey
- Laboratoire P4 INSERM - Jean Mérieux, INSERM US003, 69007, Lyon, France
| | - Manon Dirheimer
- INSERM, Délégation Régionale Auvergne Rhône-Alpes, 69500, Bron, France
| | | | | | | | - Hervé Raoul
- Laboratoire P4 INSERM - Jean Mérieux, INSERM US003, 69007, Lyon, France
| | - Frédéric Tangy
- Vaccine Innovation Laboratory, Institut Pasteur, 75015, Paris, France
| | - Sylvain Baize
- Unité de Biologie des Infections Virales Emergentes, Institut Pasteur, 69007, Lyon, France. .,Centre International de Recherche en Infectiologie (CIRI), Université de Lyon, INSERM U1111, Ecole Normale Supérieure de Lyon, Université Lyon 1, CNRS UMR5308, 69007, Lyon, France.
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11
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Grant DS, Engel EJ, Roberts Yerkes N, Kanneh L, Koninga J, Gbakie MA, Alhasan F, Kanneh FB, Kanneh IM, Kamara FK, Momoh M, Yillah MS, Foday M, Okoli A, Zeoli A, Weldon C, Bishop CM, Zheng C, Hartnett J, Chao K, Shore K, Melnik LI, Mucci M, Bond NG, Doyle P, Yenni R, Podgorski R, Ficenec SC, Moses L, Shaffer JG, Garry RF, Schieffelin JS. Seroprevalence of anti-Lassa Virus IgG antibodies in three districts of Sierra Leone: A cross-sectional, population-based study. PLoS Negl Trop Dis 2023; 17:e0010938. [PMID: 36758101 PMCID: PMC9946222 DOI: 10.1371/journal.pntd.0010938] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Revised: 02/22/2023] [Accepted: 11/09/2022] [Indexed: 02/11/2023] Open
Abstract
BACKGROUND Lassa virus (LASV), the cause of the acute viral hemorrhagic illness Lassa fever (LF), is endemic in West Africa. Infections in humans occur mainly after exposure to infected excrement or urine of the rodent-host, Mastomys natalensis. The prevalence of exposure to LASV in Sierra Leone is crudely estimated and largely unknown. This cross-sectional study aimed to establish a baseline point seroprevalence of IgG antibodies to LASV in three administrative districts of Sierra Leone and identify potential risk factors for seropositivity and LASV exposure. METHODOLOGY AND PRINCIPAL FINDINGS Between 2015 and 2018, over 10,642 participants from Kenema, Tonkolili, and Port Loko Districts were enrolled in this cross-sectional study. Previous LASV and LF epidemiological studies support classification of these districts as "endemic," "emerging," and "non-endemic", respectively. Dried blood spot samples were tested for LASV antibodies by ELISA to determine the seropositivity of participants, indicating previous exposure to LASV. Surveys were administered to each participant to assess demographic and environmental factors associated with a higher risk of exposure to LASV. Overall seroprevalence for antibodies to LASV was 16.0%. In Kenema, Port Loko, and Tonkolili Districts, seroprevalences were 20.1%, 14.1%, and 10.6%, respectively. In a multivariate analysis, individuals were more likely to be LASV seropositive if they were living in Kenema District, regardless of sex, age, or occupation. Environmental factors contributed to an increased risk of LASV exposure, including poor housing construction and proximity to bushland, forested areas, and refuse. CONCLUSIONS AND SIGNIFICANCE In this study we determine a baseline LASV seroprevalence in three districts which will inform future epidemiological, ecological, and clinical studies on LF and the LASV in Sierra Leone. The heterogeneity of the distribution of LASV and LF over both space, and time, can make the design of efficacy trials and intervention programs difficult. Having more studies on the prevalence of LASV and identifying potential hyper-endemic areas will greatly increase the awareness of LF and improve targeted control programs related to LASV.
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Affiliation(s)
- Donald S. Grant
- Lassa Fever Program, Kenema Government Hospital, Ministry of Health and Sanitation, Kenema, Sierra Leone
- College of Medicine and Allied Health Sciences, University of Sierra Leone, Freetown, Sierra Leone
| | - Emily J. Engel
- Department of Pediatrics, Sections of Pediatric Infectious Diseases, Tulane University School of Medicine, New Orleans, Louisiana, United States of America
| | - Nicole Roberts Yerkes
- Department of Pediatrics, Sections of Pediatric Infectious Diseases, Tulane University School of Medicine, New Orleans, Louisiana, United States of America
| | - Lansana Kanneh
- Lassa Fever Program, Kenema Government Hospital, Ministry of Health and Sanitation, Kenema, Sierra Leone
| | - James Koninga
- Lassa Fever Program, Kenema Government Hospital, Ministry of Health and Sanitation, Kenema, Sierra Leone
| | - Michael A. Gbakie
- Lassa Fever Program, Kenema Government Hospital, Ministry of Health and Sanitation, Kenema, Sierra Leone
| | - Foday Alhasan
- Lassa Fever Program, Kenema Government Hospital, Ministry of Health and Sanitation, Kenema, Sierra Leone
| | - Franklyn B. Kanneh
- Lassa Fever Program, Kenema Government Hospital, Ministry of Health and Sanitation, Kenema, Sierra Leone
| | - Ibrahim Mustapha Kanneh
- Lassa Fever Program, Kenema Government Hospital, Ministry of Health and Sanitation, Kenema, Sierra Leone
| | - Fatima K. Kamara
- Lassa Fever Program, Kenema Government Hospital, Ministry of Health and Sanitation, Kenema, Sierra Leone
| | - Mambu Momoh
- Lassa Fever Program, Kenema Government Hospital, Ministry of Health and Sanitation, Kenema, Sierra Leone
- Eastern Technical University of Sierra Leone, Kenema, Sierra Leone
| | - Mohamed S. Yillah
- Lassa Fever Program, Kenema Government Hospital, Ministry of Health and Sanitation, Kenema, Sierra Leone
| | - Momoh Foday
- Lassa Fever Program, Kenema Government Hospital, Ministry of Health and Sanitation, Kenema, Sierra Leone
| | - Adaora Okoli
- Department of Tropical Medicine, Tulane University School of Public Health and Tropical Medicine, Tulane University, New Orleans, Louisiana, United States of America
| | - Ashley Zeoli
- Department of Pediatrics, Sections of Pediatric Infectious Diseases, Tulane University School of Medicine, New Orleans, Louisiana, United States of America
| | - Caroline Weldon
- Department of Tropical Medicine, Tulane University School of Public Health and Tropical Medicine, Tulane University, New Orleans, Louisiana, United States of America
| | - Christopher M. Bishop
- Department of Microbiology and Immunology, Tulane University School of Medicine, New Orleans, Louisiana, United States of America
| | - Crystal Zheng
- Department of Internal Medicine, Section of Infectious Diseases, Tulane University School of Medicine, New Orleans, Louisiana, United States of America
| | - Jessica Hartnett
- Department of Pediatrics, Sections of Pediatric Infectious Diseases, Tulane University School of Medicine, New Orleans, Louisiana, United States of America
| | - Karissa Chao
- Department of Microbiology and Immunology, Tulane University School of Medicine, New Orleans, Louisiana, United States of America
| | - Kayla Shore
- Department of Tropical Medicine, Tulane University School of Public Health and Tropical Medicine, Tulane University, New Orleans, Louisiana, United States of America
| | - Lilia I. Melnik
- Department of Microbiology and Immunology, Tulane University School of Medicine, New Orleans, Louisiana, United States of America
| | - Mallory Mucci
- Department of Tropical Medicine, Tulane University School of Public Health and Tropical Medicine, Tulane University, New Orleans, Louisiana, United States of America
| | - Nell G. Bond
- Department of Microbiology and Immunology, Tulane University School of Medicine, New Orleans, Louisiana, United States of America
| | - Philip Doyle
- Department of Microbiology and Immunology, Tulane University School of Medicine, New Orleans, Louisiana, United States of America
| | - Rachael Yenni
- Department of Microbiology and Immunology, Tulane University School of Medicine, New Orleans, Louisiana, United States of America
| | - Rachel Podgorski
- Department of Tropical Medicine, Tulane University School of Public Health and Tropical Medicine, Tulane University, New Orleans, Louisiana, United States of America
| | - Samuel C. Ficenec
- Department of Internal Medicine, Tulane University School of Medicine, New Orleans, Louisiana, United States of America
| | - Lina Moses
- Department of Tropical Medicine, Tulane University School of Public Health and Tropical Medicine, Tulane University, New Orleans, Louisiana, United States of America
| | - Jeffrey G. Shaffer
- Department of Biostatistics and Data Science, Tulane University School of Public Health and Tropical Medicine, New Orleans, Louisiana, United States of America
| | - Robert F. Garry
- Department of Microbiology and Immunology, Tulane University School of Medicine, New Orleans, Louisiana, United States of America
| | - John S. Schieffelin
- Department of Pediatrics, Sections of Pediatric Infectious Diseases, Tulane University School of Medicine, New Orleans, Louisiana, United States of America
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12
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Aloke C, Obasi NA, Aja PM, Emelike CU, Egwu CO, Jeje O, Edeogu CO, Onisuru OO, Orji OU, Achilonu I. Combating Lassa Fever in West African Sub-Region: Progress, Challenges, and Future Perspectives. Viruses 2023; 15:146. [PMID: 36680186 PMCID: PMC9864412 DOI: 10.3390/v15010146] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Revised: 12/28/2022] [Accepted: 12/28/2022] [Indexed: 01/05/2023] Open
Abstract
Lassa fever (LF) is a rodent-borne disease that threatens human health in the sub-region of West Africa where the zoonotic host of Lassa virus (LASV) is predominant. Currently, treatment options for LF are limited and since no preventive vaccine is approved for its infectivity, there is a high mortality rate in endemic areas. This narrative review explores the transmission, pathogenicity of LASV, advances, and challenges of different treatment options. Our findings indicate that genetic diversity among the different strains of LASV and their ability to circumvent the immune system poses a critical challenge to the development of LASV vaccines/therapeutics. Thus, understanding the biochemistry, physiology and genetic polymorphism of LASV, mechanism of evading host immunity are essential for development of effective LASV vaccines/therapeutics to combat this lethal viral disease. The LASV nucleoprotein (NP) is a novel target for therapeutics as it functions significantly in several aspects of the viral life cycle. Consequently, LASV NP inhibitors could be employed as effective therapeutics as they will potentially inhibit LASV replication. Effective preventive control measures, vaccine development, target validation, and repurposing of existing drugs, such as ribavirin, using activity or in silico-based and computational bioinformatics, would aid in the development of novel drugs for LF management.
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Affiliation(s)
- Chinyere Aloke
- Protein Structure-Function and Research Unit, School of Molecular and Cell Biology, Faculty of Science, University of the Witwatersrand, Braamfontein, Johannesburg 2050, South Africa
- Department of Medical Biochemistry, Alex Ekwueme Federal University Ndufu-Alike, Abakaliki PMB 1010, Ebonyi State, Nigeria
| | - Nwogo Ajuka Obasi
- Department of Medical Biochemistry, Alex Ekwueme Federal University Ndufu-Alike, Abakaliki PMB 1010, Ebonyi State, Nigeria
| | - Patrick Maduabuchi Aja
- Department of Biochemistry, Faculty of Biological Sciences, Ebonyi State University, Abakaliki PMB 053, Ebonyi State, Nigeria
- Department of Biochemistry, Faculty of Medicine, Mbarara University of Science and Technology (MUST), Mbarara P.O. Box 1410, Uganda
- Department of Medical Biochemistry, Kampala International University, Bushenyi, Ishaka P.O. Box 71, Uganda
| | - Chinedum Uche Emelike
- Department of Physiology, Alex Ekwueme Federal University Ndufu-Alike, Abakaliki PMB 1010, Ebonyi State, Nigeria
| | - Chinedu Ogbonnia Egwu
- Department of Medical Biochemistry, Alex Ekwueme Federal University Ndufu-Alike, Abakaliki PMB 1010, Ebonyi State, Nigeria
| | - Olamide Jeje
- Protein Structure-Function and Research Unit, School of Molecular and Cell Biology, Faculty of Science, University of the Witwatersrand, Braamfontein, Johannesburg 2050, South Africa
| | - Chuks Oswald Edeogu
- Department of Medical Biochemistry, Faculty of Basic Medical Sciences, Ebonyi State University, Abakaliki PMB 053, Ebonyi State, Nigeria
| | - Olalekan Olugbenga Onisuru
- Protein Structure-Function and Research Unit, School of Molecular and Cell Biology, Faculty of Science, University of the Witwatersrand, Braamfontein, Johannesburg 2050, South Africa
| | - Obasi Uche Orji
- Department of Biochemistry, Faculty of Biological Sciences, Ebonyi State University, Abakaliki PMB 053, Ebonyi State, Nigeria
| | - Ikechukwu Achilonu
- Protein Structure-Function and Research Unit, School of Molecular and Cell Biology, Faculty of Science, University of the Witwatersrand, Braamfontein, Johannesburg 2050, South Africa
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13
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Brouwer PJ, Antanasijevic A, Ronk AJ, Müller-Kräuter H, Watanabe Y, Claireaux M, Perrett HR, Bijl TP, Grobben M, Umotoy JC, Schriek AI, Burger JA, Tejjani K, Lloyd NM, Steijaert TH, van Haaren MM, Sliepen K, de Taeye SW, van Gils MJ, Crispin M, Strecker T, Bukreyev A, Ward AB, Sanders RW. Lassa virus glycoprotein nanoparticles elicit neutralizing antibody responses and protection. Cell Host Microbe 2022; 30:1759-1772.e12. [PMID: 36400021 PMCID: PMC9794196 DOI: 10.1016/j.chom.2022.10.018] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Revised: 09/07/2022] [Accepted: 10/25/2022] [Indexed: 11/18/2022]
Abstract
The Lassa virus is endemic in parts of West Africa, and it causes hemorrhagic fever with high mortality. The development of a recombinant protein vaccine has been hampered by the instability of soluble Lassa virus glycoprotein complex (GPC) trimers, which disassemble into monomeric subunits after expression. Here, we use two-component protein nanoparticles consisting of trimeric and pentameric subunits to stabilize GPC in a trimeric conformation. These GPC nanoparticles present twenty prefusion GPC trimers on the surface of an icosahedral particle. Cryo-EM studies of GPC nanoparticles demonstrated a well-ordered structure and yielded a high-resolution structure of an unliganded GPC. These nanoparticles induced potent humoral immune responses in rabbits and protective immunity against the lethal Lassa virus challenge in guinea pigs. Additionally, we isolated a neutralizing antibody that mapped to the putative receptor-binding site, revealing a previously undefined site of vulnerability. Collectively, these findings offer potential approaches to vaccine and therapeutic design for the Lassa virus.
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Affiliation(s)
- Philip J.M. Brouwer
- Department of Medical Microbiology and Infection Prevention, Amsterdam University Medical Centers, Location AMC, University of Amsterdam, Amsterdam Infection & Immunity Institute, 1105 AZ Amsterdam, the Netherlands,Department of Integrative, Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Aleksandar Antanasijevic
- Department of Integrative, Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA 92037, USA,International AIDS Vaccine Initiative Neutralizing Antibody Center, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Adam J. Ronk
- Department of Pathology, University of Texas Medical Branch, Galveston, TX 77550, USA,Galveston National Laboratory, University of Texas Medical Branch, Galveston, TX 77550, USA
| | | | - Yasunori Watanabe
- School of Biological Sciences, University of Southampton, Southampton SO17 1BJ, UK
| | - Mathieu Claireaux
- Department of Medical Microbiology and Infection Prevention, Amsterdam University Medical Centers, Location AMC, University of Amsterdam, Amsterdam Infection & Immunity Institute, 1105 AZ Amsterdam, the Netherlands
| | - Hailee R. Perrett
- Department of Integrative, Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Tom P.L. Bijl
- Department of Medical Microbiology and Infection Prevention, Amsterdam University Medical Centers, Location AMC, University of Amsterdam, Amsterdam Infection & Immunity Institute, 1105 AZ Amsterdam, the Netherlands
| | - Marloes Grobben
- Department of Medical Microbiology and Infection Prevention, Amsterdam University Medical Centers, Location AMC, University of Amsterdam, Amsterdam Infection & Immunity Institute, 1105 AZ Amsterdam, the Netherlands
| | - Jeffrey C. Umotoy
- Department of Medical Microbiology and Infection Prevention, Amsterdam University Medical Centers, Location AMC, University of Amsterdam, Amsterdam Infection & Immunity Institute, 1105 AZ Amsterdam, the Netherlands
| | - Angela I. Schriek
- Department of Medical Microbiology and Infection Prevention, Amsterdam University Medical Centers, Location AMC, University of Amsterdam, Amsterdam Infection & Immunity Institute, 1105 AZ Amsterdam, the Netherlands
| | - Judith A. Burger
- Department of Medical Microbiology and Infection Prevention, Amsterdam University Medical Centers, Location AMC, University of Amsterdam, Amsterdam Infection & Immunity Institute, 1105 AZ Amsterdam, the Netherlands
| | - Khadija Tejjani
- Department of Medical Microbiology and Infection Prevention, Amsterdam University Medical Centers, Location AMC, University of Amsterdam, Amsterdam Infection & Immunity Institute, 1105 AZ Amsterdam, the Netherlands
| | - Nicole M. Lloyd
- Department of Pathology, University of Texas Medical Branch, Galveston, TX 77550, USA,Galveston National Laboratory, University of Texas Medical Branch, Galveston, TX 77550, USA
| | - Thijs H. Steijaert
- Department of Medical Microbiology and Infection Prevention, Amsterdam University Medical Centers, Location AMC, University of Amsterdam, Amsterdam Infection & Immunity Institute, 1105 AZ Amsterdam, the Netherlands
| | - Marlies M. van Haaren
- Department of Medical Microbiology and Infection Prevention, Amsterdam University Medical Centers, Location AMC, University of Amsterdam, Amsterdam Infection & Immunity Institute, 1105 AZ Amsterdam, the Netherlands
| | - Kwinten Sliepen
- Department of Medical Microbiology and Infection Prevention, Amsterdam University Medical Centers, Location AMC, University of Amsterdam, Amsterdam Infection & Immunity Institute, 1105 AZ Amsterdam, the Netherlands
| | - Steven W. de Taeye
- Department of Medical Microbiology and Infection Prevention, Amsterdam University Medical Centers, Location AMC, University of Amsterdam, Amsterdam Infection & Immunity Institute, 1105 AZ Amsterdam, the Netherlands
| | - Marit J. van Gils
- Department of Medical Microbiology and Infection Prevention, Amsterdam University Medical Centers, Location AMC, University of Amsterdam, Amsterdam Infection & Immunity Institute, 1105 AZ Amsterdam, the Netherlands
| | - Max Crispin
- School of Biological Sciences, University of Southampton, Southampton SO17 1BJ, UK
| | - Thomas Strecker
- Institute of Virology, Philipps University Marburg, 35043 Marburg, Germany
| | - Alexander Bukreyev
- Department of Pathology, University of Texas Medical Branch, Galveston, TX 77550, USA,Galveston National Laboratory, University of Texas Medical Branch, Galveston, TX 77550, USA
| | - Andrew B. Ward
- Department of Integrative, Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA 92037, USA,International AIDS Vaccine Initiative Neutralizing Antibody Center, The Scripps Research Institute, La Jolla, CA 92037, USA,Corresponding author
| | - Rogier W. Sanders
- Department of Medical Microbiology and Infection Prevention, Amsterdam University Medical Centers, Location AMC, University of Amsterdam, Amsterdam Infection & Immunity Institute, 1105 AZ Amsterdam, the Netherlands,Department of Microbiology and Immunology, Weill Medical College of Cornell University, New York, NY 10021, USA,Corresponding author
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14
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Wada YH, Ogunyinka IA, Yusuff KB, Ochu CL, Yahaya M, Khalid GM, Mutalub YB, Adeniye SB. Knowledge of Lassa fever, its prevention and control practices and their predictors among healthcare workers during an outbreak in Northern Nigeria: A multi-centre cross-sectional assessment. PLoS Negl Trop Dis 2022; 16:e0010259. [PMID: 35286303 PMCID: PMC9045733 DOI: 10.1371/journal.pntd.0010259] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Revised: 03/24/2022] [Accepted: 02/13/2022] [Indexed: 11/18/2022] Open
Abstract
Background The year 2020 Lassa fever (LF) outbreak had the greatest disease burden and
this can place an enormous strain on the already overstretched healthcare
system and can potentially increase morbidity and mortality due to
infectious diseases. Therefore, having a knowledgeable healthcare workforce with appropriate
skills and competencies to prevent and manage outbreaks of a neglected
infectious disease such as LF in Nigeria will potentially enhance public
health. Thus, this survey assessed the level of knowledge of LF and its
prevention and control (PC) measures amongst the healthcare workers (HCWs)
during a LF outbreak in Katsina state, Nigeria. Methodology/Principal findings During this cross-sectional survey, HCWs complete a validated 29-item
questionnaire comprising 18 items on the knowledge of LF and its PC measures
and an item on global self-evaluation of their LF knowledge. Psychometric
properties of the questionnaire were evaluated. Chi-square and binary
logistic regression analyses were conducted. Out of 435 HCWs invited, a total of 400 participated in the study (92%
response rate). The majority of participants (51.8%) demonstrated inadequate
LF knowledge, with 62.9% of those scoring low having a high self-perception
of their LF knowledge with the global scale. This LF knowledge
over-estimation was predicted by LF training status (odds ratio (OR) 2.53;
95% CI: 1.49–4.30; p = 0.001). The level of LF knowledge
and its PC measures among the study participants was low (11.60±8.14, 64.4%)
and predicted by participants’ LF training status (OR 2.06; 95% CI:
1.19–3.57; p = 0.009), place of work (OR 1.82; 95% CI:
1.07–3.08; p = 0.03) and their designations (OR 2.40; 95%
CI: 1.10–5.22; p = 0.03). Conclusion The level of knowledge of LF and its PC measures among the HCWs surveyed was
suboptimal and participants’ LF training status, place of work and
occupational category were the significant predictors. In addition, LF
knowledge overestimation on a global scale was observed among a majority of
HCWs and this was also predicted by LF training status. Therefore, there is
a critical need for health authorities in Nigeria to prioritize continuous
on-the-job training of HCWs on priority neglected tropical diseases such as
Lassa fever. In about five decades in Nigeria, Lassa fever (LF) has infected 3897 and caused
1319 deaths (including 71 healthcare workers (HCWs)) giving a case fatality rate
of 33.8% for confirmed cases in Nigeria. Poor knowledge of LF and its prevention
and control (PC) measures amongst HCWs can lead to non-adherence to LF safety
protocols, healthcare-associated infections, poor patient outcomes, and even the
death of infected HCWs. In addition, LF knowledge over-estimation may lead to
mismanagement of LF cases with potential fatal consequences. Therefore, this
study assessed if the nine different cadres of HCWs interviewed from four health
facilities during an LF outbreak in Katsina, Nigeria have the appropriate level
of LF knowledge. Using a validated questionnaire, data were collected from 400
HCWs and then analyzed with Statistical Package for the Social Sciences (SPSS)
Version 25. Results were tabulated and associations between the variables
determined. More than half of the HCWs demonstrated inadequate LF knowledge with
nearly two out of three of these HCWs over-estimating their LF knowledge.
However, adequate LF knowledge was predicted by training on LF and this in turn
predicted LF knowledge over-estimation.
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Affiliation(s)
| | - Ibrahim Abayomi Ogunyinka
- Department of Clinical Pharmacy and Pharmacy Practice, Faculty of
Pharmaceutical Sciences, Usmanu Danfodiyo University, Sokoto,
Nigeria
- * E-mail:
| | - Kazeem Babatunde Yusuff
- Department of Clinical Pharmacy and Practice, College of Pharmacy, QU
Health, Qatar University, Doha, Qatar
| | - Chinwe Lucia Ochu
- Prevention, Programmes and Knowledge Management, Nigeria Centre for
Disease Control, Abuja, Nigeria
| | - Mohammed Yahaya
- Department of Medical Microbiology and Parasitology, Usmanu Danfodiyo
University, Sokoto, Nigeria
| | - Garba Mohammed Khalid
- Department of Pharmaceutics and Pharmaceutical Technology, Bayero
University, Kano, Nigeria
| | - Yahkub Babatunde Mutalub
- Department of Clinical Pharmacology, College of Medical Sciences,
Abubakar Tafawa Balewa University, Bauchi, Nigeria
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15
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Olayinka AT, Elimian K, Ipadeola O, Dan-Nwafor C, Gibson J, Ochu C, Furuse Y, Iniobong A, Akano A, Enenche L, Onoja M, Uzoho C, Ugbogulu N, Makava F, Arinze C, Namara G, Muwanguzi E, Jan K, Ukponu W, Okwor T, Anueyiagu C, Saleh M, Ahumibe A, Eneh C, Ilori E, Mba N, Ihekweazu C. Analysis of sociodemographic and clinical factors associated with Lassa fever disease and mortality in Nigeria. PLOS GLOBAL PUBLIC HEALTH 2022; 2:e0000191. [PMID: 36962735 PMCID: PMC10022364 DOI: 10.1371/journal.pgph.0000191] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Accepted: 07/19/2022] [Indexed: 11/18/2022]
Abstract
Over past decades, there has been increasing geographical spread of Lassa fever (LF) cases across Nigeria and other countries in West Africa. This increase has been associated with significant morbidity and mortality despite increasing focus on the disease by both local and international scientists. Many of these studies on LF have been limited to few specialised centres in the country. This study was done to identify sociodemographic and clinical predictors of LF disease and related deaths across Nigeria. We analysed retrospective surveillance data on suspected LF cases collected during January-June 2018 and 2019. Multivariable logistic regression analyses were used to identify the factors independently associated with laboratory-confirmed LF diagnosis, and with LF-related deaths. There were confirmed 815 of 1991 suspected LF cases with complete records during this period. Of these, 724/815 confirmed cases had known clinical outcomes, of whom 100 died. LF confirmation was associated with presentation of gastrointestinal tract (aOR 3.47, 95% CI: 2.79-4.32), ear, nose and throat (aOR 2.73, 95% CI: 1.80-4.15), general systemic (aOR 2.12, 95% CI: 1.65-2.70) and chest/respiratory (aOR 1.71, 95% CI: 1.28-2.29) symptoms. Other factors were being male (aOR 1.32, 95% CI: 1.06-1.63), doing business/trading (aOR 2.16, 95% CI: 1.47-3.16) and farming (aOR 1.73, 95% CI: 1.12-2.68). Factors associated with LF mortality were a one-year increase in age (aOR 1.03, 95% CI: 1.01-1.04), bleeding (aOR 2.07, 95% CI: 1.07-4.00), and central nervous manifestations (aOR 5.02, 95% CI: 3.12-10.16). Diverse factors were associated with both LF disease and related death. A closer look at patterns of clinical variables would be helpful to support early detection and management of cases. The findings would also be useful for planning preparedness and response interventions against LF in the country and region.
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Affiliation(s)
| | - Kelly Elimian
- Nigeria Centre for Disease Control, Abuja, FCT, Nigeria
| | | | | | - Jack Gibson
- University of Nottingham, Nottingham, United Kingdom
| | - Chinwe Ochu
- Nigeria Centre for Disease Control, Abuja, FCT, Nigeria
| | - Yuki Furuse
- World Health Organisation, Abuja, FCT, Nigeria
| | | | - Adejoke Akano
- Nigeria Centre for Disease Control, Abuja, FCT, Nigeria
| | - Lorna Enenche
- Nigeria Centre for Disease Control, Abuja, FCT, Nigeria
| | - Michael Onoja
- Nigeria Centre for Disease Control, Abuja, FCT, Nigeria
| | | | - Nkem Ugbogulu
- Nigeria Centre for Disease Control, Abuja, FCT, Nigeria
| | - Favour Makava
- Nigeria Centre for Disease Control, Abuja, FCT, Nigeria
| | | | | | | | - Kamji Jan
- Nigeria Centre for Disease Control, Abuja, FCT, Nigeria
| | - Winifred Ukponu
- Georgetown University Centre for Global Health Practice and Impact, Abuja, Nigeria
| | - Tochi Okwor
- Nigeria Centre for Disease Control, Abuja, FCT, Nigeria
| | | | - Muhammad Saleh
- Centers for Disease Prevention and Control, Abuja, Nigeria
| | | | - Chibuzo Eneh
- Nigeria Centre for Disease Control, Abuja, FCT, Nigeria
| | - Elsie Ilori
- Nigeria Centre for Disease Control, Abuja, FCT, Nigeria
| | - Nwando Mba
- Nigeria Centre for Disease Control, Abuja, FCT, Nigeria
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16
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Adeke A, Ajayi N, Azuogu B, Chika-Igwenyi N, Onwe E. The Role of Partnership in Lassa Fever Prevention and Control in a Tertiary Health Facility in Southeastern Nigeria. NIGERIAN JOURNAL OF MEDICINE 2022. [DOI: 10.4103/njm.njm_32_21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
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17
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Thielebein A, Ighodalo Y, Taju A, Olokor T, Omiunu R, Esumeh R, Ebhodaghe P, Ekanem A, Igenegbale G, Giwa R, Renevey A, Hinzmann J, Müller J, Pallasch E, Pahlmann M, Guedj J, Nwatuzor J, Femi Babatunde O, Adomeh DI, Asogun D, Akpede N, Okogbenin S, Günther S, Oestereich L, Duraffour S, Ogbaini-Emovon E. Virus persistence after recovery from acute Lassa fever in Nigeria: a 2-year interim analysis of a prospective longitudinal cohort study. THE LANCET MICROBE 2022; 3:e32-e40. [DOI: 10.1016/s2666-5247(21)00178-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Revised: 05/22/2021] [Accepted: 06/30/2021] [Indexed: 12/13/2022] Open
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18
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Obionu IM, Ochu CL, Ukponu W, Okwor T, Dan-Nwafor C, Ilori E, Ihekweazu C. Evaluation of infection prevention and control practices in Lassa fever treatment centers in north-central Nigeria during an ongoing Lassa fever outbreak. J Infect Prev 2021; 22:275-282. [PMID: 34880950 DOI: 10.1177/17571774211035838] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2020] [Accepted: 07/12/2021] [Indexed: 11/16/2022] Open
Abstract
Background Outbreaks of Lassa fever (LF) in Nigeria have become more frequent, with increasing more healthcare worker infections. Prevention of infection is dependent on strict compliance to infection prevention and control (IPC) practices in treatment centres where patients are managed. Objective To evaluate IPC practices during an ongoing LF outbreak in the two major tertiary hospitals serving as the referral LF treatment centres in the north-central region of Nigeria. Methods This cross-sectional survey was carried out by the IPC subteam of the National Rapid Response Team of the Nigeria Centre for Disease Control (NCDC) deployed to Plateau State, north-central Nigeria during the 2019 LF outbreak. Information on IPC in these facilities was collected using the NCDC viral haemorrhagic fevers (VHFs) isolation and treatment facility IPC survey tool. Results Both treatment centres had national VHF IPC isolation guidelines and few health workers had received IPC training. In both centres, there were no clearly demarcated entry points for staff going into clinical areas after putting on personal protective equipment, and there were also no standard operating procedures in place for reporting occupational exposure of staff to infected blood or body fluids in both centres. Discussion The LF treatment centers located in Plateau State during the 2019 LF outbreak were not fully implementing the national VHF IPC guidelines. Periodic assessments of IPC are recommended for proper management of cases and effective control of LF in the State.
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Affiliation(s)
- Ifeoma Maureen Obionu
- Department of Community Medicine, University of Nigeria Teaching Hospital, Enugu, Nigeria
| | - Chinwe Lucia Ochu
- Nigeria Centre for Disease Control, Abuja, Federal Capital Territory, Nigeria
| | - Winifred Ukponu
- Nigeria Centre for Disease Control, Abuja, Federal Capital Territory, Nigeria
| | - Tochi Okwor
- Nigeria Centre for Disease Control, Abuja, Federal Capital Territory, Nigeria
| | - Chioma Dan-Nwafor
- Nigeria Centre for Disease Control, Abuja, Federal Capital Territory, Nigeria
| | - Elsie Ilori
- Nigeria Centre for Disease Control, Abuja, Federal Capital Territory, Nigeria
| | - Chikwe Ihekweazu
- Nigeria Centre for Disease Control, Abuja, Federal Capital Territory, Nigeria
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19
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Nwafor CD, Ilori E, Olayinka A, Ochu C, Olorundare R, Edeh E, Okwor T, Oyebanji O, Namukose E, Ukponu W, Olugbile M, Adekanye U, Chandra N, Bolt H, Namara G, Ipadeola O, Furuse Y, Woldetsadik S, Akano A, Iniobong A, Amedu M, Anueyiagu C, Bakare L, Ahumibe A, Joseph G, Eneh C, Saleh M, Dhamari N, Okoli I, Kachalla M, Okea R, Okenyi C, Makava F, Makwe C, Ugbogulu N, Fonkeng F, Aniaku E, Agogo E, Mba N, Aruna O, Nguku P, Ihekweazu C. The One Health approach to incident management of the 2019 Lassa fever outbreak response in Nigeria. One Health 2021; 13:100346. [PMID: 34820499 PMCID: PMC8600060 DOI: 10.1016/j.onehlt.2021.100346] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2021] [Revised: 11/07/2021] [Accepted: 11/07/2021] [Indexed: 11/18/2022] Open
Abstract
Globally, effective emergency response to disease outbreaks is usually affected by weak coordination. However, coordination using an incident management system (IMS) in line with a One Health approach involving human, environment, and animal health with collaborations between government and non-governmental agencies result in improved response outcome for zoonotic diseases such as Lassa fever (LF). We provide an overview of the 2019 LF outbreak response in Nigeria using the IMS and One Health approach. The response was coordinated via ten Emergency Operation Centre (EOC) response pillars. Cardinal response activities included activation of EOC, development of an incident action plan, deployment of One Health rapid response teams to support affected states, mid-outbreak review and after-action review meetings. Between 1st January and 29th December 2019, of the 5057 people tested for LF, 833 were confirmed positive from 23 States, across 86 Local Government Areas. Of the 833 confirmed cases, 650 (78%) were from hotspot States of Edo (36%), Ondo (26%) and Ebonyi (16%). Those in the age-group 21–40 years (47%) were mostly affected, with a male to female ratio of 1:1. Twenty healthcare workers were affected. Two LF naïve states Kebbi and Zamfara, reported confirmed cases for the first time during this period. The outbreak peaked earlier in the year compared to previous years, and the emergency phase of the outbreak was declared over by epidemiological week 17 based on low national threshold composite indicators over a period of six consecutive weeks. Multisectoral and multidisciplinary strategic One Health EOC coordination at all levels facilitated the swift containment of Nigeria's large LF outbreak in 2019. It is therefore imperative to embrace One Health approach embedded within the EOC to holistically address the increasing LF incidence in Nigeria.
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Affiliation(s)
| | - Elsie Ilori
- Nigeria Centre for Disease Control, Abuja, Nigeria
| | | | - Chinwe Ochu
- Nigeria Centre for Disease Control, Abuja, Nigeria
| | | | - Edwin Edeh
- World Health Organisation, Abuja, Nigeria
| | - Tochi Okwor
- Nigeria Centre for Disease Control, Abuja, Nigeria.,World Health Organisation, Abuja, Nigeria
| | | | | | | | | | - Usman Adekanye
- Nigeria Ministry of Defense, Health Implementation Program, Nigeria
| | | | - Hikaru Bolt
- UK Public Health Rapid Support Team, London, United Kingdom
| | | | | | | | | | | | | | | | | | - Lawal Bakare
- Nigeria Centre for Disease Control, Abuja, Nigeria.,World Health Organisation, Abuja, Nigeria
| | | | | | - Chibuzo Eneh
- Nigeria Centre for Disease Control, Abuja, Nigeria
| | | | | | - Ihekerenma Okoli
- Federal Ministry of Agriculture and Rural Development, Abuja, Nigeria
| | - Mairo Kachalla
- Federal Ministry of Agriculture and Rural Development, Abuja, Nigeria
| | - Rita Okea
- Federal Ministry of Environment, Abuja, Nigeria
| | | | | | | | | | | | | | | | - Nwando Mba
- Nigeria Centre for Disease Control, Abuja, Nigeria
| | - Olusola Aruna
- Public Health England, International Health Regulations (IHR) Strengthening Project, Abuja, Nigeria
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20
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Spruill-Harrell B, Pérez-Umphrey A, Valdivieso-Torres L, Cao X, Owen RD, Jonsson CB. Impact of Predator Exclusion and Habitat on Seroprevalence of New World Orthohantavirus Harbored by Two Sympatric Rodents within the Interior Atlantic Forest. Viruses 2021; 13:1963. [PMID: 34696393 PMCID: PMC8538774 DOI: 10.3390/v13101963] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Revised: 09/19/2021] [Accepted: 09/24/2021] [Indexed: 11/17/2022] Open
Abstract
Understanding how perturbations to trophic interactions influence virus-host dynamics is essential in the face of ongoing biodiversity loss and the continued emergence of RNA viruses and their associated zoonoses. Herein, we investigated the role of predator exclusion on rodent communities and the seroprevalence of hantaviruses within the Reserva Natural del Bosque Mbaracayú (RNBM), which is a protected area of the Interior Atlantic Forest (IAF). In the IAF, two sympatric rodent reservoirs, Akodon montensis and Oligoryzomys nigripes, harbor Jaborá and Juquitiba hantavirus (JABV, JUQV), respectively. In this study, we employed two complementary methods for predator exclusion: comprehensive fencing and trapping/removal. The goal of exclusion was to preclude the influence of predation on small mammals on the sampling grids and thereby potentially reduce rodent mortality. Following baseline sampling on three grid pairs with different habitats, we closed the grids and began predator removal. By sampling three habitat types, we controlled for habitat-specific effects, which is important for hantavirus-reservoir dynamics in neotropical ecosystems. Our six-month predator exclusion experiment revealed that the exclusion of terrestrial mammalian predators had little influence on the rodent community or the population dynamics of A. montensis and O. nigripes. Instead, fluctuations in species diversity and species abundances were influenced by sampling session and forest degradation. These results suggest that seasonality and landscape composition play dominant roles in the prevalence of hantaviruses in rodent reservoirs in the IAF ecosystem.
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Affiliation(s)
- Briana Spruill-Harrell
- Department of Microbiology, Immunology and Biochemistry, University of Tennessee Health Science Center, Memphis, TN 38163, USA;
| | - Anna Pérez-Umphrey
- School of Renewable Natural Resources, Louisiana State University and AgCenter, 227 RNR Building, Baton Rouge, LA 70803, USA;
| | | | - Xueyuan Cao
- Department of Nursing-Acute/Tert Care, University of Tennessee Health Science Center, Memphis, TN 38163, USA;
| | - Robert D. Owen
- Centro para el Desarrollo de la Investigación Científica, Asunción C.P. 1371, Paraguay;
- Department of Biological Sciences, Texas Tech University, Lubbock, TX 79409, USA
| | - Colleen B. Jonsson
- Department of Microbiology, Immunology and Biochemistry, University of Tennessee Health Science Center, Memphis, TN 38163, USA;
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21
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Merson L, Bourner J, Jalloh S, Erber A, Salam AP, Flahault A, Olliaro PL. Clinical characterization of Lassa fever: A systematic review of clinical reports and research to inform clinical trial design. PLoS Negl Trop Dis 2021; 15:e0009788. [PMID: 34547033 PMCID: PMC8486098 DOI: 10.1371/journal.pntd.0009788] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2021] [Revised: 10/01/2021] [Accepted: 09/03/2021] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Research is urgently needed to reduce the morbidity and mortality of Lassa fever (LF), including clinical trials to test new therapies and to verify the efficacy and safety of the only current treatment recommendation, ribavirin, which has a weak clinical evidence base. To help establish a basis for the development of an adaptable, standardised clinical trial methodology, we conducted a systematic review to identify the clinical characteristics and outcomes of LF and describe how LF has historically been defined and assessed in the scientific literature. METHODOLOGY Primary clinical studies and reports of patients with suspected and confirmed diagnosis of LF published in the peer-reviewed literature before 15 April 2021 were included. Publications were selected following a two-stage screening of abstracts, then full-texts, by two independent reviewers at each stage. Data were extracted, verified, and summarised using descriptive statistics. RESULTS 147 publications were included, primarily case reports (36%), case series (28%), and cohort studies (20%); only 2 quasi-randomised studies (1%) were found. Data are mostly from Nigeria (52% of individuals, 41% of publications) and Sierra Leone (42% of individuals, 31% of publications). The results corroborate the World Health Organisation characterisation of LF presentation. However, a broader spectrum of presenting symptoms is evident, such as gastrointestinal illness and other nervous system and musculoskeletal disorders that are not commonly included as indicators of LF. The overall case fatality ratio was 30% in laboratory-confirmed cases (1896/6373 reported in 109 publications). CONCLUSION Systematic review is an important tool in the clinical characterisation of diseases with limited publications. The results herein provide a more complete understanding of the spectrum of disease which is relevant to clinical trial design. This review demonstrates the need for coordination across the LF research community to generate harmonised research methods that can contribute to building a strong evidence base for new treatments and foster confidence in their integration into clinical care.
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Affiliation(s)
- Laura Merson
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
- Institute of Global Health, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Josephine Bourner
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
| | | | - Astrid Erber
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
- Department of Epidemiology, Center for Public Health, Medical University of Vienna, Vienna, Austria
| | - Alex Paddy Salam
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Antoine Flahault
- Institute of Global Health, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Piero L. Olliaro
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
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22
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Holt A, Hornsey E, Seale AC, Rohan H, Bausch DG, Ihekweazu C, Okwor T. A mixed-methods analysis of personal protective equipment used in Lassa fever treatment centres in Nigeria. Infect Prev Pract 2021; 3:100168. [PMID: 34430843 PMCID: PMC8367797 DOI: 10.1016/j.infpip.2021.100168] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Accepted: 07/28/2021] [Indexed: 11/09/2022] Open
Abstract
Background Lassa fever (LF) is a viral haemorrhagic fever endemic in West Africa. Lassa virus is maintained in and spread to humans from rodents, with occasional secondary human-to-human transmission. Present recommendations for personal protective equipment (PPE) for care of patients with LF generally follow those for filovirus diseases. However, the need for such high-level PPE for LF, which is thought to be considerably less transmissible between humans than filoviruses, is unclear. Aim In Nigerian Lassa Treatment Centres (LTCs) we aimed to describe current PPE practices, identify barriers and facilitators to implementation of existing guidance, and assess healthcare workers' understanding. This would inform the development of future PPE guidelines for LF. Methods We performed a mixed-methods study, including short cross-sectional surveys of PPE used in LTCs, observations of practice, and in-depth interviews with key informants. We described the quantitative data and we conducted a thematic analysis of qualitative data. Findings Our survey of 74 HCWs found that approximately half reported problems with recommended PPE. In three LTCs PPE was used highly variably. Full PPE, as recommended in Nigeria CDC guidelines, was used in less than a quarter (21%) of interactions. In-depth interviews suggested this was based on availability and HCWs' own risk assessments. Conclusion Without specific guidance on Lassa, the current approach is both resource and labour-intensive, where these are both limited. This has led to low adherence by health care workers, whose own experience indicates lower risk. The evidence-base to inform PPE required for LF must be improved to inform a more tailored approach.
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Affiliation(s)
- Andrew Holt
- London School of Hygiene & Tropical Medicine, London, UK
| | - Emilio Hornsey
- UK Public Health Rapid Support Team, London, UK.,Public Health England, UK
| | - Anna C Seale
- London School of Hygiene & Tropical Medicine, London, UK.,UK Public Health Rapid Support Team, London, UK
| | - Hana Rohan
- London School of Hygiene & Tropical Medicine, London, UK.,UK Public Health Rapid Support Team, London, UK
| | - Daniel G Bausch
- London School of Hygiene & Tropical Medicine, London, UK.,UK Public Health Rapid Support Team, London, UK.,Public Health England, UK
| | | | - Tochi Okwor
- Nigeria Center for Disease Control, Abuja, Nigeria
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23
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Common Themes in Zoonotic Spillover and Disease Emergence: Lessons Learned from Bat- and Rodent-Borne RNA Viruses. Viruses 2021; 13:v13081509. [PMID: 34452374 PMCID: PMC8402684 DOI: 10.3390/v13081509] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Revised: 07/22/2021] [Accepted: 07/28/2021] [Indexed: 12/18/2022] Open
Abstract
Rodents (order Rodentia), followed by bats (order Chiroptera), comprise the largest percentage of living mammals on earth. Thus, it is not surprising that these two orders account for many of the reservoirs of the zoonotic RNA viruses discovered to date. The spillover of these viruses from wildlife to human do not typically result in pandemics but rather geographically confined outbreaks of human infection and disease. While limited geographically, these viruses cause thousands of cases of human disease each year. In this review, we focus on three questions regarding zoonotic viruses that originate in bats and rodents. First, what biological strategies have evolved that allow RNA viruses to reside in bats and rodents? Second, what are the environmental and ecological causes that drive viral spillover? Third, how does virus spillover occur from bats and rodents to humans?
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24
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Arruda LB, Haider N, Olayemi A, Simons D, Ehichioya D, Yinka-Ogunleye A, Ansumana R, Thomason MJ, Asogun D, Ihekweazu C, Fichet-Calvet E, Kock RA. The niche of One Health approaches in Lassa fever surveillance and control. Ann Clin Microbiol Antimicrob 2021; 20:29. [PMID: 33894784 PMCID: PMC8067790 DOI: 10.1186/s12941-021-00431-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Accepted: 04/12/2021] [Indexed: 12/20/2022] Open
Abstract
Lassa fever (LF), a zoonotic illness, represents a public health burden in West African countries where the Lassa virus (LASV) circulates among rodents. Human exposure hinges significantly on LASV ecology, which is in turn shaped by various parameters such as weather seasonality and even virus and rodent-host genetics. Furthermore, human behaviour, despite playing a key role in the zoonotic nature of the disease, critically affects either the spread or control of human-to-human transmission. Previous estimations on LF burden date from the 80s and it is unclear how the population expansion and the improvement on diagnostics and surveillance methods have affected such predictions. Although recent data have contributed to the awareness of epidemics, the real impact of LF in West African communities will only be possible with the intensification of interdisciplinary efforts in research and public health approaches. This review discusses the causes and consequences of LF from a One Health perspective, and how the application of this concept can improve the surveillance and control of this disease in West Africa.
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Affiliation(s)
- Liã Bárbara Arruda
- Centre for Clinical Microbiology, Division of Infection and Immunity, University College London, London, UK.
| | - Najmul Haider
- The Royal Veterinary College, University of London, Hatfield, UK
| | - Ayodeji Olayemi
- Natural History Museum, Obafemi Awolowo University, Ile Ife, Nigeria
| | - David Simons
- The Royal Veterinary College, University of London, Hatfield, UK
| | - Deborah Ehichioya
- Institute of Lassa Fever Research and Control, Irrua Specialist Teaching Hospital, Irrua, Nigeria.,Department of Microbiology, Ambrose Alli University, Ekpoma, Nigeria
| | | | - Rashid Ansumana
- School of Community Health Sciences, Njala University, Bo, Sierra Leone
| | - Margaret J Thomason
- Centre for Clinical Microbiology, Division of Infection and Immunity, University College London, London, UK
| | - Danny Asogun
- Institute of Lassa Fever Research and Control, Irrua Specialist Teaching Hospital, Irrua, Nigeria
| | | | | | - Richard A Kock
- The Royal Veterinary College, University of London, Hatfield, UK
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25
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Hansen F, Jarvis MA, Feldmann H, Rosenke K. Lassa Virus Treatment Options. Microorganisms 2021; 9:microorganisms9040772. [PMID: 33917071 PMCID: PMC8067676 DOI: 10.3390/microorganisms9040772] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2021] [Revised: 04/02/2021] [Accepted: 04/03/2021] [Indexed: 12/27/2022] Open
Abstract
Lassa fever causes an approximate 5000 to 10,000 deaths annually in West Africa and cases have been imported into Europe and the Americas, challenging public health. Although Lassa virus was first described over 5 decades ago in 1969, no treatments or vaccines have been approved to treat or prevent infection. In this review, we discuss current therapeutics in the development pipeline for the treatment of Lassa fever, focusing on those that have been evaluated in humans or animal models. Several treatments, including the antiviral favipiravir and a human monoclonal antibody cocktail, have shown efficacy in preclinical rodent and non-human primate animal models and have potential for use in clinical settings. Movement of the promising preclinical treatment options for Lassa fever into clinical trials is critical to continue addressing this neglected tropical disease.
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Affiliation(s)
- Frederick Hansen
- Laboratory of Virology, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, MT 59840, USA
| | - Michael A Jarvis
- The Vaccine Group Ltd., University of Plymouth, Plymouth PL4 8AA, UK
| | - Heinz Feldmann
- Laboratory of Virology, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, MT 59840, USA
| | - Kyle Rosenke
- Laboratory of Virology, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, MT 59840, USA
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26
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Lassa fever outcomes and prognostic factors in Nigeria (LASCOPE): a prospective cohort study. LANCET GLOBAL HEALTH 2021; 9:e469-e478. [PMID: 33740408 PMCID: PMC7970450 DOI: 10.1016/s2214-109x(20)30518-0] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Revised: 11/11/2020] [Accepted: 12/03/2020] [Indexed: 12/17/2022]
Abstract
Background Lassa fever is a viral haemorrhagic fever endemic in parts of west Africa. New treatments are needed to decrease mortality, but pretrial reference data on the disease characteristics are scarce. We aimed to document baseline characteristics and outcomes for patients hospitalised with Lassa fever in Nigeria. Methods We did a prospective cohort study (LASCOPE) at the Federal Medical Centre in Owo, Nigeria. All patients admitted with confirmed Lassa fever were invited to participate and asked to give informed consent. Patients of all ages, including newborn infants, were eligible for inclusion, as were pregnant women. All participants received standard supportive care and intravenous ribavirin according to Nigeria Centre for Disease Control guidelines and underwent systematic biological monitoring for 30 days. Patients' characteristics, care received, mortality, and associated factors were recorded using standard WHO forms. We used univariable and multivariable logistic regression models to investigate an association between baseline characteristics and mortality at day 30. Findings Between April 5, 2018, and March 15, 2020, 534 patients with confirmed Lassa fever were admitted to hospital, of whom 510 (96%) gave consent and were included in the analysis. The cohort included 258 (51%) male patients, 252 (49%) female patients, 426 (84%) adults, and 84 (16%) children (younger than 18 years). The median time between first symptoms and hospital admission was 8 days (IQR 7–13). At baseline, 176 (38%) of 466 patients had a Lassa fever RT-PCR cycle threshold (Ct) lower than 30. From admission to end of follow-up, 120 (25%) of 484 reached a National Early Warning Score (second version; NEWS2) of 7 or higher, 67 (14%) of 495 reached a Kidney Disease–Improving Global Outcome (KDIGO) stage of 2 or higher, and 41 (8%) of 510 underwent dialysis. All patients received ribavirin for a median of 10 days (IQR 9–13). 62 (12%) patients died (57 [13%] adults and five [6%] children). The median time to death was 3 days (1–6). The baseline factors independently associated with mortality were the following: age 45 years or older (adjusted odds ratio 16·30, 95% CI 5·31–50·30), NEWS2 of 7 or higher (4·79, 1·75–13·10), KDIGO grade 2 or higher (7·52, 2·66–21·20), plasma alanine aminotransferase 3 or more times the upper limit of normal (4·96, 1·69–14·60), and Lassa fever RT-PCR Ct value lower than 30 (4·65, 1·50–14·50). Interpretation Our findings comprehensively document clinical and biological characteristics of patients with Lassa fever and their relationship with mortality, providing prospective estimates that could be useful for designing future therapeutic trials. Such trials comparing new Lassa fever treatments to a standard of care should take no more than 15% as the reference mortality rate and consider adopting a combination of mortality and need for dialysis as the primary endpoint. Funding Institut National de la Santé et de la Recherche Médicale, University of Oxford, EU, UK Department for International Development, Wellcome Trust, French Ministry of Foreign Affairs, Agence Nationale de Recherches sur le SIDA et les hépatites virales, French National Research Institute for Sustainable Development.
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27
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Fischer RJ, Purushotham JN, van Doremalen N, Sebastian S, Meade-White K, Cordova K, Letko M, Jeremiah Matson M, Feldmann F, Haddock E, LaCasse R, Saturday G, Lambe T, Gilbert SC, Munster VJ. ChAdOx1-vectored Lassa fever vaccine elicits a robust cellular and humoral immune response and protects guinea pigs against lethal Lassa virus challenge. NPJ Vaccines 2021; 6:32. [PMID: 33654106 PMCID: PMC7925663 DOI: 10.1038/s41541-021-00291-x] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Accepted: 01/27/2021] [Indexed: 01/31/2023] Open
Abstract
Lassa virus (LASV) infects hundreds of thousands of individuals each year, highlighting the need for the accelerated development of preventive, diagnostic, and therapeutic interventions. To date, no vaccine has been licensed for LASV. ChAdOx1-Lassa-GPC is a chimpanzee adenovirus-vectored vaccine encoding the Josiah strain LASV glycoprotein precursor (GPC) gene. In the following study, we show that ChAdOx1-Lassa-GPC is immunogenic, inducing robust T-cell and antibody responses in mice. Furthermore, a single dose of ChAdOx1-Lassa-GPC fully protects Hartley guinea pigs against morbidity and mortality following lethal challenge with a guinea pig-adapted LASV (strain Josiah). By contrast, control vaccinated animals reached euthanasia criteria 10-12 days after infection. Limited amounts of LASV RNA were detected in the tissues of vaccinated animals. Viable LASV was detected in only one animal receiving a single dose of the vaccine. A prime-boost regimen of ChAdOx1-Lassa-GPC in guinea pigs significantly increased antigen-specific antibody titers and cleared viable LASV from the tissues. These data support further development of ChAdOx1-Lassa-GPC and testing in non-human primate models of infection.
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Affiliation(s)
- Robert J. Fischer
- grid.419681.30000 0001 2164 9667Laboratory of Virology, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rocky Mountain Laboratories, Hamilton, MT USA
| | - Jyothi N. Purushotham
- grid.419681.30000 0001 2164 9667Laboratory of Virology, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rocky Mountain Laboratories, Hamilton, MT USA ,grid.4991.50000 0004 1936 8948The Jenner Institute, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Neeltje van Doremalen
- grid.419681.30000 0001 2164 9667Laboratory of Virology, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rocky Mountain Laboratories, Hamilton, MT USA
| | - Sarah Sebastian
- grid.4991.50000 0004 1936 8948The Jenner Institute, Nuffield Department of Medicine, University of Oxford, Oxford, UK ,Present Address: Vaccitech Limited, Oxford, UK
| | - Kimberly Meade-White
- grid.419681.30000 0001 2164 9667Laboratory of Virology, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rocky Mountain Laboratories, Hamilton, MT USA
| | - Kathleen Cordova
- grid.419681.30000 0001 2164 9667Rocky Mountain Veterinary Branch, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, MT USA
| | - Michael Letko
- grid.419681.30000 0001 2164 9667Laboratory of Virology, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rocky Mountain Laboratories, Hamilton, MT USA ,grid.30064.310000 0001 2157 6568Paul G. Allen School of Global Animal Health, Washington State University, Pullman, WA USA
| | - M. Jeremiah Matson
- grid.419681.30000 0001 2164 9667Laboratory of Virology, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rocky Mountain Laboratories, Hamilton, MT USA ,grid.36425.360000 0001 2216 9681Marshall University Joan C. Edwards School of Medicine, Huntington, WV USA
| | - Friederike Feldmann
- grid.419681.30000 0001 2164 9667Rocky Mountain Veterinary Branch, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, MT USA
| | - Elaine Haddock
- grid.419681.30000 0001 2164 9667Laboratory of Virology, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rocky Mountain Laboratories, Hamilton, MT USA
| | - Rachel LaCasse
- grid.419681.30000 0001 2164 9667Rocky Mountain Veterinary Branch, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, MT USA
| | - Greg Saturday
- grid.419681.30000 0001 2164 9667Rocky Mountain Veterinary Branch, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, MT USA
| | - Teresa Lambe
- grid.4991.50000 0004 1936 8948The Jenner Institute, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Sarah C. Gilbert
- grid.4991.50000 0004 1936 8948The Jenner Institute, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Vincent J. Munster
- grid.419681.30000 0001 2164 9667Laboratory of Virology, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rocky Mountain Laboratories, Hamilton, MT USA
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Chika-Igwenyi NM, Harrison RE, Psarra C, Gil-Cuesta J, Gulamhusein M, Onwe EO, Onoh RC, Unigwe US, Ajayi NA, Nnadozie UU, Ojide CK, Nwidi DU, Ezeanosike O, Sampson E, Adeke AS, Ugwu CN, Anebonam U, Tshiang JK, Maikere J, Reid A. Early onset of neurological features differentiates two outbreaks of Lassa fever in Ebonyi state, Nigeria during 2017-2018. PLoS Negl Trop Dis 2021; 15:e0009169. [PMID: 33684118 PMCID: PMC7984835 DOI: 10.1371/journal.pntd.0009169] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Revised: 03/22/2021] [Accepted: 01/22/2021] [Indexed: 01/15/2023] Open
Abstract
Lassa fever (LF) is an acute viral haemorrhagic illness with various non-specific clinical manifestations. Neurological symptoms are rare at the early stage of the disease, but may be seen in late stages, in severely ill patients.The aim of this study was to describe the epidemiological evolution, socio-demographic profiles, clinical characteristics, and outcomes of patients seen during two Lassa fever outbreaks in Ebonyi State, between December 2017 and December 2018. Routinely collected clinical data from all patients admitted to the Virology Centre of the hospital during the period were analysed retrospectively. Out of a total of 83 cases, 70(84.3%) were RT-PCR confirmed while 13 (15.7%) were probable cases. Sixty-nine (83.1%) patients were seen in outbreak 1 of whom 53.6% were urban residents, while 19%, 15%, and 10% were farmers, students and health workers respectively. There were 14 (16.8%) patients, seen in second outbreak with 92.9% rural residents. There were differences in clinical symptoms, signs and laboratory findings between the two outbreaks. The case fatality rates were 29.9% in outbreak 1 and 85.7% for outbreak 2. Neurological features and abnormal laboratory test results were associated with higher mortality rate, seen in outbreak 2. This study revealed significant differences between the two outbreaks. Of particular concern was the higher case fatality during the outbreak 2 which may be from a more virulent strain of the Lassa virus. This has important public health implications and further molecular studies are needed to better define its characteristics.
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Affiliation(s)
- Nneka M. Chika-Igwenyi
- Department of Medicine, Alex Ekwueme Federal University Teaching Hospital Abakaliki, Abakaliki, Ebonyi, Nigeria
| | | | - Christina Psarra
- Médecins sans Frontières Operational Research Unit (LuxOR), Operational Centre Brussels, Belgium
| | - Julita Gil-Cuesta
- Médecins sans Frontières Operational Research Unit (LuxOR), Operational Centre Brussels, Belgium
| | - Maria Gulamhusein
- Médecins sans Frontières Operational Research Unit (LuxOR), Operational Centre Brussels, Belgium
| | - Emeka O. Onwe
- Department of Paediatrics, Alex Ekwueme Federal University Teaching Hospital Abakaliki, Abakaliki, Ebonyi, Nigeria
| | - Robinson C. Onoh
- Department of Obstetrics and Gynaecology, Alex Ekwueme Federal University Teaching Hospital Abakaliki, Abakaliki, Ebonyi, Nigeria
| | - Uche S. Unigwe
- Department of Medicine, Alex Ekwueme Federal University Teaching Hospital Abakaliki, Abakaliki, Ebonyi, Nigeria
- University of Nigeria Teaching Hospital, Ituku Ozalla Enugu, Nigeria
| | - Nnennaya A. Ajayi
- Department of Medicine, Alex Ekwueme Federal University Teaching Hospital Abakaliki, Abakaliki, Ebonyi, Nigeria
| | - Ugochukwu U. Nnadozie
- Division of Plastic Surgery, Department of Surgery, Alex Ekwueme Federal University Teaching Hospital Abakaliki, Abakaliki, Ebonyi, Nigeria
| | - Chiedozie K. Ojide
- Department of Medical Microbiology, Alex Ekwueme Federal University Teaching Hospital Abakaliki, Abakaliki, Ebonyi, Nigeria
- Virology Laboratory, Virology Centre,AlexEkwueme Federal University Teaching Hospital Abakaliki, Abakaliki, Ebonyi, Nigeria
| | - Damian U. Nwidi
- Department of Medicine, Alex Ekwueme Federal University Teaching Hospital Abakaliki, Abakaliki, Ebonyi, Nigeria
| | - Obumneme Ezeanosike
- Department of Paediatrics, Alex Ekwueme Federal University Teaching Hospital Abakaliki, Abakaliki, Ebonyi, Nigeria
| | - Emeka Sampson
- Ebonyi State Ministry of Health, Abakaliki, Ebonyi, Nigeria
| | - Azuka S. Adeke
- Department of Community Medicine, Alex Ekwueme Federal University Teaching Hospital Abakiliki, Abakaliki, Ebonyi, Nigeria
| | - Collins N. Ugwu
- Department of Medicine, Alex Ekwueme Federal University Teaching Hospital Abakaliki, Abakaliki, Ebonyi, Nigeria
| | | | | | | | - Anthony Reid
- Médecins sans Frontières Operational Research Unit (LuxOR), Operational Centre Brussels, Belgium
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29
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Furuse Y. [Epidemiology of Viral Hemorrhagic Fever in Africa]. Uirusu 2021; 71:11-18. [PMID: 35526990 DOI: 10.2222/jsv.71.11] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
A variety of viral hemorrhagic fevers such as Ebola virus disease exist in Africa and impose a great threat in public health due to their high fatality. It is considered to be difficult to eradicate the etiological agents of viral hemorrhagic fever because they have non-human natural hosts. Therefore, the importance of public health measures remains high in addition to the urgent need for the development of medicines for treatment and prevention. Furthermore, public health measures directly lead to the accumulation of epidemiological knowledge about the diseases. As an infectious disease consultant for the World Health Organization, I have been involved with public health activities including the development of clinical guidelines, the establishment of laboratory diagnostic systems, the training for infection, prevention and control, the planning of budget for outbreak response, and the analysis of epidemiological data. On the last point, I reported the situation of Ebola virus disease outbreak in Liberia, 2014-2015 and Lassa fever outbreak in Nigeria, 2018-2019 describing the risk factors, morbidity, and mortality of the diseases.
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Affiliation(s)
- Yuki Furuse
- Institute for Frontier Life and Medical Sciences, Kyoto University
- Hakubi Center for Advanced Research, Kyoto University
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30
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Wilkason C, Lee C, Sauer LM, Nuzzo J, McClelland A. Assessing and Reducing Risk to Healthcare Workers in Outbreaks. Health Secur 2020; 18:205-211. [PMID: 32559156 DOI: 10.1089/hs.2019.0131] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
The 2014-2016 West African Ebola epidemic was devastating in many respects, not least of which was the impact on healthcare systems and their health workforce. Healthcare workers-including physicians, clinical officers, nurses, midwives, and community health workers-serve on the front lines of efforts to detect, control, and stop the spread of disease. Risk mitigation strategies, including infection prevention and control (IPC) practices, are meant to keep healthcare workers safe from occupational exposure to disease and to protect patients from healthcare-associated infections. Despite ongoing IPC efforts, steady rates of both healthcare-associated and healthcare worker infections signal that these mitigation measures have been inadequate at all levels and present a potential critical point of failure in efforts to limit and control the spread of outbreaks. The fact that healthcare workers continue to be infected or are a source of infection during public health emergencies reveals a weakness in global preparedness efforts. Identification of key points of failure-both within the health system and during emergencies-is the first step to mitigating risk of exposure. A 2-pronged solution is proposed to address long-term gaps in the health system that impact infection control and emergency response: prioritization of IPC for epidemic preparedness at a global level and development and use of rapid risk assessments to prioritize risk mitigation strategies for IPC. Without global support, evidence, and systems in place to support the lives of healthcare workers, the lives of their patients and the health system in general are also at risk.
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Affiliation(s)
- Colby Wilkason
- Colby Wilkason, MPH, is Technical Advisor for Prevent Epidemics
| | - Christopher Lee
- Christopher T. Lee, MD, is Senior Technical Advisor for Prevent Epidemics
| | - Lauren M Sauer
- Lauren M. Sauer, MS, is Director of Operations and an Assistant Professor, Department of Emergency Medicine, Johns Hopkins Office of Critical Event Preparedness and Response, Johns Hopkins University School of Medicine
| | - Jennifer Nuzzo
- Jennifer Nuzzo, DrPH, SM, is a Senior Scholar, Johns Hopkins Center for Health Security, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD
| | - Amanda McClelland
- Amanda McClelland, MPHTM, is Senior Vice President; all are at Resolve to Save Lives, New York, New York
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31
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Okoro OA, Bamgboye E, Dan-Nwafor C, Umeokonkwo C, Ilori E, Yashe R, Balogun M, Nguku P, Ihekweazu C. Descriptive epidemiology of Lassa fever in Nigeria, 2012-2017. Pan Afr Med J 2020; 37:15. [PMID: 33062117 PMCID: PMC7532845 DOI: 10.11604/pamj.2020.37.15.21160] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Accepted: 05/08/2020] [Indexed: 11/23/2022] Open
Abstract
Introduction Lassa fever, an acute viral hemorrhagic zoonotic disease is endemic in some parts of Nigeria. The disease alert and outbreak threshold are known; however, there has been a shift from the previous seasonal transmission pattern to an all year-round transmission. We described data on Lassa fever and highlighted the magnitude of the disease over a six-year period. Methods we conducted a secondary data analyses of Lassa fever specific surveillance data from the Integrated Disease Surveillance and Response (IDSR) records of all states in Nigeria over a six-year period (2012-2017). Results a total of 5974 suspected cases were reported within the study period; of these, 759 (12.7%) were confirmed by laboratory diagnosis. Highest number of cases was recorded in 2012. Edo and Ondo states in the southern region of the country were mostly affected within the study period. The seasonal trend of Lassa fever cases showed peaks within January to March, except for year 2015. Conclusion there was a high burden of Lassa fever in Nigeria especially in the southern part. Lassa fever transmission occurs all year-round with peaks in January and March. There is need to develop preparedness plans and define thresholds for Lassa fever epidemic.
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Affiliation(s)
| | - Eniola Bamgboye
- Department of Epidemiology and Medical Statistics, University of Ibadan, Ibadan, Nigeria
| | | | - Chukwuma Umeokonkwo
- Department of Community Medicine, Alex Ekwueme Federal University Teaching Hospital Abakaliki, Ebonyi State, Nigeria
| | - Elsie Ilori
- Nigeria Centre for Disease Control, Abuja, Nigeria
| | | | - Muhammad Balogun
- African Field Epidemiology Network, Nigeria Country Office, Abuja, Nigeria
| | - Patrick Nguku
- African Field Epidemiology Network, Nigeria Country Office, Abuja, Nigeria
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32
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Bayesian estimation of Lassa virus epidemiological parameters: Implications for spillover prevention using wildlife vaccination. PLoS Negl Trop Dis 2020; 14:e0007920. [PMID: 32956349 PMCID: PMC7529244 DOI: 10.1371/journal.pntd.0007920] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2019] [Revised: 10/01/2020] [Accepted: 07/20/2020] [Indexed: 12/31/2022] Open
Abstract
Lassa virus is a significant burden on human health throughout its endemic region in West Africa, with most human infections the result of spillover from the primary rodent reservoir of the virus, the natal multimammate mouse, M. natalensis. Here we develop a Bayesian methodology for estimating epidemiological parameters of Lassa virus within its rodent reservoir and for generating probabilistic predictions for the efficacy of rodent vaccination programs. Our approach uses Approximate Bayesian Computation (ABC) to integrate mechanistic mathematical models, remotely-sensed precipitation data, and Lassa virus surveillance data from rodent populations. Using simulated data, we show that our method accurately estimates key model parameters, even when surveillance data are available from only a relatively small number of points in space and time. Applying our method to previously published data from two villages in Guinea estimates the time-averaged R0 of Lassa virus to be 1.74 and 1.54 for rodent populations in the villages of Bantou and Tanganya, respectively. Using the posterior distribution for model parameters derived from these Guinean populations, we evaluate the likely efficacy of vaccination programs relying on distribution of vaccine-laced baits. Our results demonstrate that effective and durable reductions in the risk of Lassa virus spillover into the human population will require repeated distribution of large quantities of vaccine. Lassa virus is a chronic source of illness throughout West Africa, and is considered to be a threat for widespread emergence. Because most human infections result from contact with infected rodents, interventions that reduce the number of rodents infected with Lassa virus represent promising opportunities for reducing the public health burden of this disease. Evaluating how well alternative interventions are likely to perform is complicated by our relatively poor understanding of viral epidemiology within the reservoir population. Here we develop a novel statistical approach that couples mathematical models and viral surveillance data from rodent populations to robustly estimate key epidemiological parameters. Applying our method to existing data from Guinea yields well-resolved parameter estimates and allows us to simulate a variety of rodent vaccination programs. Together, our results demonstrate that rodent vaccination alone is unlikely to be an effective tool for reducing the public health burden of Lassa fever within West Africa.
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Kenmoe S, Tchatchouang S, Ebogo-Belobo JT, Ka'e AC, Mahamat G, Guiamdjo Simo RE, Bowo-Ngandji A, Demeni Emoh CP, Che E, Tchami Ngongang D, Amougou-Atsama M, Nzukui ND, Mbongue Mikangue CA, Mbaga DS, Kenfack S, Kingue Bebey SR, Amvongo Adjia N, Efietngab AN, Tazokong HR, Modiyinji AF, Kengne-Nde C, Sadeuh-Mba SA, Njouom R. Systematic review and meta-analysis of the epidemiology of Lassa virus in humans, rodents and other mammals in sub-Saharan Africa. PLoS Negl Trop Dis 2020; 14:e0008589. [PMID: 32845889 PMCID: PMC7478710 DOI: 10.1371/journal.pntd.0008589] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Revised: 09/08/2020] [Accepted: 07/13/2020] [Indexed: 12/27/2022] Open
Abstract
Accurate data on the Lassa virus (LASV) human case fatality rate (CFR) and the prevalence of LASV in humans, rodents and other mammals are needed for better planning of actions that will ultimately reduce the burden of LASV infection in sub-Saharan Africa. In this systematic review with meta-analysis, we searched PubMed, Scopus, Africa Journal Online, and African Index Medicus from 1969 to 2020 to obtain studies that reported enough data to calculate LASV infection CFR or prevalence. Study selection, data extraction, and risk of bias assessment were conducted independently. We extracted all measures of current, recent, and past infections with LASV. Prevalence and CFR estimates were pooled using a random-effect meta-analysis. Factors associated with CFR, prevalence, and sources of between-study heterogeneity were determined using subgroup and metaregression analyses. This review was registered with PROSPERO, CRD42020166465. We initially identified 1,399 records and finally retained 109 reports that contributed to 291 prevalence records from 25 countries. The overall CFR was 29.7% (22.3-37.5) in humans. Pooled prevalence of LASV infection was 8.7% (95% confidence interval: 6.8-10.8) in humans, 3.2% (1.9-4.6) in rodents, and 0.7% (0.0-2.3) in other mammals. Subgroup and metaregression analyses revealed a substantial statistical heterogeneity explained by higher prevalence in tissue organs, in case-control, in hospital outbreak, and surveys, in retrospective studies, in urban and hospital setting, in hospitalized patients, and in West African countries. This study suggests that LASV infections is an important cause of death in humans and that LASV are common in humans, rodents and other mammals in sub-Saharan Africa. These estimates highlight disparities between sub-regions, and population risk profiles. Western Africa, and specific key populations were identified as having higher LASV CFR and prevalence, hence, deserving more attention for cost-effective preventive interventions.
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Affiliation(s)
- Sebastien Kenmoe
- Department of Virology, Centre Pasteur of Cameroon, Yaoundé, Cameroon
| | | | - Jean Thierry Ebogo-Belobo
- Medical Research Centre, Institut of Medical Research and Medicinal Plants Studies, Yaoundé, Cameroon
| | - Aude Christelle Ka'e
- Virology Department, Chantal Biya International Reference Centre, Yaoundé, Cameroon
| | - Gadji Mahamat
- Department of Microbiology, Faculty of Science, The University of Yaounde I, Yaoundé, Cameroon
| | | | - Arnol Bowo-Ngandji
- Department of Microbiology, Faculty of Science, The University of Yaounde I, Yaoundé, Cameroon
| | | | - Emmanuel Che
- Vaccinology and Biobank, Chantal Biya International Reference Centre, Yaounde, Cameroon
| | - Dimitri Tchami Ngongang
- Department of Microbiology, Faculty of Science, The University of Yaounde I, Yaoundé, Cameroon
| | - Marie Amougou-Atsama
- Department of Virology, Centre Pasteur of Cameroon, Yaoundé, Cameroon
- Medical Research Centre, Institut of Medical Research and Medicinal Plants Studies, Yaoundé, Cameroon
| | - Nathalie Diane Nzukui
- School of Health Sciences-Catholic University of Central Africa, Department of Medical Microbiology, Yaoundé, Cameroon
| | | | - Donatien Serge Mbaga
- Department of Microbiology, Faculty of Science, The University of Yaounde I, Yaoundé, Cameroon
| | - Sorel Kenfack
- Department of Microbiology, Faculty of Science, The University of Yaounde I, Yaoundé, Cameroon
| | | | - Nathalie Amvongo Adjia
- Medical Research Centre, Institut of Medical Research and Medicinal Plants Studies, Yaoundé, Cameroon
| | - Atembeh Noura Efietngab
- Medical Research Centre, Institut of Medical Research and Medicinal Plants Studies, Yaoundé, Cameroon
| | - Hervé Raoul Tazokong
- Department of Microbiology, Faculty of Science, The University of Yaounde I, Yaoundé, Cameroon
| | - Abdou Fatawou Modiyinji
- Department of Virology, Centre Pasteur of Cameroon, Yaoundé, Cameroon
- Department of Animals Biology and Physiology, Faculty of Science, The University of Yaoundé I, Yaoundé, Cameroon
| | - Cyprien Kengne-Nde
- Epidemiological Surveillance, Evaluation and Research Unit, National AIDS Control Committee, Yaoundé, Cameroon
| | | | - Richard Njouom
- Department of Virology, Centre Pasteur of Cameroon, Yaoundé, Cameroon
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Wolf T, Ellwanger R, Goetsch U, Wetzstein N, Gottschalk R. Fifty years of imported Lassa fever: a systematic review of primary and secondary cases. J Travel Med 2020; 27:5808990. [PMID: 32219400 DOI: 10.1093/jtm/taaa035] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/27/2019] [Revised: 03/08/2020] [Indexed: 01/15/2023]
Abstract
RATIONALE FOR SYSTEMATIC REVIEW Lassa fever is the most common cause of imported haemorrhagic fevers cases in non-endemic countries. As a disease with a high case fatality rate that has regularly caused clusters of nosocomial transmission in endemic areas, prompt diagnosis is vital. We conducted a systematic review of imported cases of the last 50 years with the aim of defining the clinical and epidemiological characteristics that will enhance early diagnosis, prompt initiation of treatment and an appropriate public health response to Lassa fever cases. METHODS We performed a retrospective, systematic review of 36 primary and two secondary cases of Lassa fever in non-endemic countries outside West Africa by searching the PubMed database. This yielded 56 relevant publications that were included in our analysis. RESULTS The case fatality rate of 35.1% for imported cases was higher than that reported for endemic countries. The majority of patients showed clinical features consistent with Lassa fever and had a typical exposure. There was a considerable delay in diagnosis in imported cases with high associated numbers of contacts. Ribavirin was rarely used for post-exposure prophylaxis. Only two secondary transmissions occurred. Thirty-one percent of patients received Lassa fever-specific treatment and five required intensive care. CONCLUSIONS Although importation of Lassa fever to non-endemic countries is a rare event, it has repeatedly happened over five decades. Suspicion of Lassa fever should be based on careful consideration of clinical features and exposure history in order to assist early diagnosis in returning travellers from West Africa.
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Affiliation(s)
- Timo Wolf
- Department of Internal Medicine II-Infectious Diseases, University Hospital Frankfurtxs, Frankfurt, Germany
| | - Regina Ellwanger
- Department of Internal Medicine II-Infectious Diseases, University Hospital Frankfurtxs, Frankfurt, Germany.,Health Protection Authority, Municipality of Frankfurt am Main, Frankfurt, Germany
| | - Udo Goetsch
- Health Protection Authority, Municipality of Frankfurt am Main, Frankfurt, Germany
| | - Nils Wetzstein
- Department of Internal Medicine II-Infectious Diseases, University Hospital Frankfurtxs, Frankfurt, Germany
| | - Rene Gottschalk
- Health Protection Authority, Municipality of Frankfurt am Main, Frankfurt, Germany.,Institute of Medical Virology, University Hospital Frankfurt, Frankfurt, Germany
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35
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Asogun DA, Günther S, Akpede GO, Ihekweazu C, Zumla A. Lassa Fever: Epidemiology, Clinical Features, Diagnosis, Management and Prevention. Infect Dis Clin North Am 2020; 33:933-951. [PMID: 31668199 DOI: 10.1016/j.idc.2019.08.002] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Lassa fever outbreaks West Africa have caused up to 10,000 deaths annually. Primary infection occurs from contact with Lassa virus-infected rodents and exposure to their excreta, blood, or meat. Incubation takes 2 to 21 days. Symptoms are difficult to distinguish from malaria, typhoid, dengue, yellow fever, and other viral hemorrhagic fevers. Clinical manifestations range from asymptomatic, to mild, to severe fulminant disease. Ribavirin can improve outcomes. Overall mortality is between 1% and 15%. Lassa fever should be considered in the differential diagnosis with travel to West Africa. There is an urgent need for rapid field-friendly diagnostics and preventive vaccine.
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Affiliation(s)
- Danny A Asogun
- Department of Public Health, College of Medicine, Ambrose Alli University, Ekpoma, Nigeria; Department of Public Health, Institute of Lassa Fever Research and Control, Irrua Specialist Teaching Hospital, P.M.B 008, Kilometre 87, Benin City-Auchi Road, Irrua, Nigeria.
| | - Stephan Günther
- Bernhard-Nocht Institute for Tropical Medicine, Strab 74, Hamburg 20359, Germany; German Centre for Infection Research (DZIF), Partner Site Hamburg, Hamburg, Germany
| | - George O Akpede
- Department of Paediatrics, Faculty of Clinical Sciences, College of Medicine, Ambrose Alli University, Ekpoma, Nigeria
| | - Chikwe Ihekweazu
- Nigeria Centre for Disease Control, Plot 801, Ebitu Ukiwe Street, Jabi, Abuja, Nigeria
| | - Alimuddin Zumla
- Center for Clinical Microbiology, University College London, Royal Free Campus 2nd Floor, Rowland Hill Street, London NW3 2PF, United Kingdom
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36
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High crossreactivity of human T cell responses between Lassa virus lineages. PLoS Pathog 2020; 16:e1008352. [PMID: 32142546 PMCID: PMC7080273 DOI: 10.1371/journal.ppat.1008352] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Revised: 03/18/2020] [Accepted: 01/24/2020] [Indexed: 12/27/2022] Open
Abstract
Lassa virus infects hundreds of thousands of people each year across rural West Africa, resulting in a high number of cases of Lassa fever (LF), a febrile disease associated with high morbidity and significant mortality. The lack of approved treatments or interventions underscores the need for an effective vaccine. At least four viral lineages circulate in defined regions throughout West Africa with substantial interlineage nucleotide and amino acid diversity. An effective vaccine should be designed to elicit Lassa virus specific humoral and cell mediated immunity across all lineages. Most current vaccine candidates use only lineage IV antigens encoded by Lassa viruses circulating around Sierra Leone, Liberia, and Guinea but not Nigeria where lineages I-III are found. As previous infection is known to protect against disease from subsequent exposure, we sought to determine whether LF survivors from Nigeria and Sierra Leone harbor memory T cells that respond to lineage IV antigens. Our results indicate a high degree of cross-reactivity of CD8+ T cells from Nigerian LF survivors to lineage IV antigens. In addition, we identified regions within the Lassa virus glycoprotein complex and nucleoprotein that contributed to these responses while T cell epitopes were not widely conserved across our study group. These data are important for current efforts to design effective and efficient vaccine candidates that can elicit protective immunity across all Lassa virus lineages. Lassa virus (LASV), the causative agent of the hemorrhagic illness Lassa fever (LF), is found throughout West Africa. Humans are usually infected after contact with infected rodent excreta or aerosolized virus. The mortality rate among hospitalized LF cases is high and no effective treatments or vaccines exist. A vaccine effective against the four main lineages of LASV is needed to protect susceptible individuals across West Africa. To understand how this protection could occur, we examined the immune responses of LF survivors from two different regions of West Africa. As previous infection with Lassa virus protects from disease after subsequent exposure, the immune response of LF survivors provides a model of protective immunity that could be induced after vaccination. We found that LASV strains from lineages different from those that infected the LF survivors efficiently activated memory CD8+ T cell responses. We identified regions within LASV proteins that elicit memory responses in the majority of individuals. From these data, we propose that an effective vaccine that protects against lineages across West Africa should be designed to elicit memory CD8+ T cell responses in addition to antibody responses.
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