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Hus KK, Buczkowicz J, Pietrowska M, Petrilla V, Petrillová M, Legáth J, Litschka-Koen T, Bocian A. Venom diversity in Naja mossambica: Insights from proteomic and immunochemical analyses reveal intraspecific differences. PLoS Negl Trop Dis 2024; 18:e0012057. [PMID: 38557658 PMCID: PMC11008852 DOI: 10.1371/journal.pntd.0012057] [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: 10/31/2023] [Revised: 04/11/2024] [Accepted: 03/07/2024] [Indexed: 04/04/2024] Open
Abstract
BACKGROUND Intraspecific variations in snake venom composition have been extensively documented, contributing to the diverse clinical effects observed in envenomed patients. Understanding these variations is essential for developing effective snakebite management strategies and targeted antivenom therapies. We aimed to comprehensively investigate venoms from three distinct populations of N. mossambica from Eswatini, Limpopo, and KwaZulu-Natal regions in Africa in terms of their protein composition and reactivity with three commercial antivenoms (SAIMR polyvalent, EchiTAb+ICP, and Antivipmyn Africa). METHODOLOGY/PRINCIPAL FINDINGS Naja mossambica venoms from Eswatini region exhibited the highest content of neurotoxic proteins, constituting 20.70% of all venom proteins, compared to Limpopo (13.91%) and KwaZulu-Natal (12.80%), and was characterized by the highest diversity of neurotoxic proteins, including neurotoxic 3FTxs, Kunitz-type inhibitors, vespryns, and mamba intestinal toxin 1. KwaZulu-Natal population exhibited considerably lower cytotoxic 3FTx, higher PLA2 content, and significant diversity in low-abundant proteins. Conversely, Limpopo venoms demonstrated the least diversity as demonstrated by electrophoretic and mass spectrometry analyses. Immunochemical assessments unveiled differences in venom-antivenom reactivity, particularly concerning low-abundance proteins. EchiTAb+ICP antivenom demonstrated superior reactivity in serial dilution ELISA assays compared to SAIMR polyvalent. CONCLUSIONS/SIGNIFICANCE Our findings reveal a substantial presence of neurotoxic proteins in N. mossambica venoms, challenging previous understandings of their composition. Additionally, the detection of numerous peptides aligning to uncharacterized proteins or proteins with unknown functions underscores a critical issue with existing venom protein databases, emphasizing the substantial gaps in our knowledge of snake venom protein components. This underscores the need for enhanced research in this domain. Moreover, our in vitro immunological assays suggest EchiTAb+ICP's potential as an alternative to SAIMR antivenom, requiring confirmation through prospective in vivo neutralization studies.
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Affiliation(s)
- Konrad K. Hus
- Department of Biotechnology and Bioinformatics, Faculty of Chemistry, Rzeszow University of Technology, Rzeszow, Poland
| | - Justyna Buczkowicz
- Department of Biotechnology and Bioinformatics, Faculty of Chemistry, Rzeszow University of Technology, Rzeszow, Poland
| | - Monika Pietrowska
- Maria Sklodowska-Curie National Research Institute of Oncology, Gliwice, Poland
| | - Vladimír Petrilla
- Department of Biology and Physiology, University of Veterinary Medicine and Pharmacy, Košice, Slovakia
- Zoological Department, Zoological Garden Košice, Košice-Kavečany, Slovakia
| | - Monika Petrillová
- Department of General Competencies, University of Veterinary Medicine and Pharmacy, Košice, Slovakia
| | - Jaroslav Legáth
- Department of Biotechnology and Bioinformatics, Faculty of Chemistry, Rzeszow University of Technology, Rzeszow, Poland
- Department of Pharmacology and Toxicology, University of Veterinary Medicine and Pharmacy, Košice, Slovakia
| | | | - Aleksandra Bocian
- Department of Biotechnology and Bioinformatics, Faculty of Chemistry, Rzeszow University of Technology, Rzeszow, Poland
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Benhammou D, Chippaux JP, Ntone R, Madec Y, Amta P, Noel G, Karl FN, Perilhou A, Matchim L, Sanchez M, Ndifon M, Clauteaux P, Eteki L, Boum Y, Nkwescheu AS, Taieb F. Snakebites in Cameroon: Tolerance of a Snake Antivenom (Inoserp™ PAN-AFRICA) in Africa in Real-Life Conditions. Toxins (Basel) 2024; 16:165. [PMID: 38668590 PMCID: PMC11053651 DOI: 10.3390/toxins16040165] [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: 02/06/2024] [Revised: 03/08/2024] [Accepted: 03/15/2024] [Indexed: 04/29/2024] Open
Abstract
Snakebite envenomation (SBE) is a public health issue in sub-Saharan countries. Antivenom is the only etiological treatment. Excellent tolerance is essential in managing SBE successfully. This study aimed to evaluate tolerance of InoserpTM PAN-AFRICA (IPA). It was conducted on fourteen sites across Cameroon. IPA was administered intravenously and repeated at the same dose every two hours if needed. Early and late tolerance was assessed by the onset of clinical signs within two hours and at a visit two weeks or more after the first IPA administration, respectively. Over 20 months, 447 patients presenting with a snakebite were included. One dose of IPA was administered to 361 patients and repeated at least once in 106 patients. No significant difference was shown between the proportion of adverse events in patients who received IPA (266/361, 73.7%) and those who did not (69/85, 81.2%) (p = 0.95). Adverse reactions, probably attributable to IPA, were identified in four (1.1%) patients, including one severe (angioedema) and three mild. All these reactions resolved favorably. None of the serious adverse events observed in twelve patients were attributed to IPA. No signs of late intolerance were observed in 302 patients. Tolerance appears to be satisfactory. The availability of effective and well-tolerated antivenoms would reduce the duration of treatment and prevent most disabilities and/or deaths.
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Affiliation(s)
- David Benhammou
- Emerging Diseases Epidemiology Unit, Institut Pasteur, Paris Cité University, F-75015 Paris, France; (D.B.)
| | - Jean-Philippe Chippaux
- MERIT Unit, Institut de Recherche pour le Développement, Paris Cité University, F-75006 Paris, France
| | - Rodrigue Ntone
- Epicentre Yaounde, Yaounde BP 12069, Cameroon; (R.N.); (F.N.K.); (L.M.); (M.N.); (L.E.)
| | - Yoann Madec
- Emerging Diseases Epidemiology Unit, Institut Pasteur, Paris Cité University, F-75015 Paris, France; (D.B.)
| | - Pierre Amta
- Tokombere Hospital, Tokombere, Mora BP 74, Cameroon;
| | - Gaëlle Noel
- Institut Pasteur, Translational Research Center, Paris Cité University, F-75015 Paris, France; (G.N.); (P.C.)
| | - Fai Njuwa Karl
- Epicentre Yaounde, Yaounde BP 12069, Cameroon; (R.N.); (F.N.K.); (L.M.); (M.N.); (L.E.)
| | - Anaïs Perilhou
- Institut Pasteur, Clinical Research Coordination Center, Paris Cité University, F-75015 Paris, France;
| | - Lucrece Matchim
- Epicentre Yaounde, Yaounde BP 12069, Cameroon; (R.N.); (F.N.K.); (L.M.); (M.N.); (L.E.)
| | - Marie Sanchez
- Institut Pasteur, Data Management Core Facility, Paris Cité University, F-75015 Paris, France;
| | - Mark Ndifon
- Epicentre Yaounde, Yaounde BP 12069, Cameroon; (R.N.); (F.N.K.); (L.M.); (M.N.); (L.E.)
| | - Pedro Clauteaux
- Institut Pasteur, Translational Research Center, Paris Cité University, F-75015 Paris, France; (G.N.); (P.C.)
| | - Lucrèce Eteki
- Epicentre Yaounde, Yaounde BP 12069, Cameroon; (R.N.); (F.N.K.); (L.M.); (M.N.); (L.E.)
| | - Yap Boum
- Epicentre Yaounde, Yaounde BP 12069, Cameroon; (R.N.); (F.N.K.); (L.M.); (M.N.); (L.E.)
- Institut Pasteur de Bangui, Bangui BP 923, Central African Republic
- Faculté de Médecine et de Sciences Biomédicales, Yaounde I University, Yaounde BP 1364, Cameroon
| | | | - Fabien Taieb
- Institut Pasteur Medical Center, Paris Cité University, F-75015 Paris, France
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Solano G, Cunningham S, Edge RJ, Duran G, Sanchez A, Villalta M, Clare RH, Wilkinson MC, Marriott AE, Abada C, Menzies SK, Keen M, Lalloo DG, Stienstra Y, Abouyannis M, Casewell NR, León G, Ainsworth S. African polyvalent antivenom can maintain pharmacological stability and ability to neutralise murine venom lethality for decades post-expiry: evidence for increasing antivenom shelf life to aid in alleviating chronic shortages. BMJ Glob Health 2024; 9:e014813. [PMID: 38485142 PMCID: PMC10941113 DOI: 10.1136/bmjgh-2023-014813] [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] [Accepted: 02/25/2024] [Indexed: 03/17/2024] Open
Abstract
INTRODUCTION Antivenom is a lifesaving medicine for treating snakebite envenoming, yet there has been a crisis in antivenom supply for many decades. Despite this, substantial quantities of antivenom stocks expire before use. This study has investigated whether expired antivenoms retain preclinical quality and efficacy, with the rationale that they could be used in emergency situations when in-date antivenom is unavailable. METHODS Using WHO guidelines and industry test requirements, we examined the in vitro stability and murine in vivo efficacy of eight batches of the sub-Saharan African antivenom, South African Institute for Medical Research polyvalent, that had expired at various times over a period of 30 years. RESULTS We demonstrate modest declines in immunochemical stability, with antivenoms older than 25 years having high levels of turbidity. In vitro preclinical analysis demonstrated all expired antivenoms retained immunological recognition of venom antigens and the ability to inhibit key toxin families. All expired antivenoms retained comparable in vivo preclinical efficacy in preventing the lethal effects of envenoming in mice versus three regionally and medically important venoms. CONCLUSIONS This study provides strong rationale for stakeholders, including manufacturers, regulators and health authorities, to explore the use of expired antivenom more broadly, to aid in alleviating critical shortages in antivenom supply in the short term and the extension of antivenom shelf life in the longer term.
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Affiliation(s)
- Gabriela Solano
- Instituto Clodomiro Picado, Universidad de Costa Rica, San Jose, Costa Rica
| | | | - Rebecca J Edge
- Liverpool School of Tropical Medicine, Liverpool, UK
- Department of Infection Biology and Microbiomes, University of Liverpool, Liverpool, UK
| | - Gina Duran
- Instituto Clodomiro Picado, Universidad de Costa Rica, San Jose, Costa Rica
| | - Adriana Sanchez
- Instituto Clodomiro Picado, Universidad de Costa Rica, San Jose, Costa Rica
| | - Mauren Villalta
- Instituto Clodomiro Picado, Universidad de Costa Rica, San Jose, Costa Rica
| | | | | | - Amy E Marriott
- Liverpool School of Tropical Medicine, Liverpool, UK
- Department of Infection Biology and Microbiomes, University of Liverpool, Liverpool, UK
| | - Camille Abada
- Liverpool School of Tropical Medicine, Liverpool, UK
| | | | - Molly Keen
- Liverpool School of Tropical Medicine, Liverpool, UK
| | - David G Lalloo
- Liverpool School of Tropical Medicine, Liverpool, UK
- Malawi Liverpool Wellcome Trust Clinical Research Programme, Blantyre, Malawi
| | - Ymkje Stienstra
- Liverpool School of Tropical Medicine, Liverpool, UK
- Department of Internal Medicine/Infectious Diseases, University of Groningen, Groningen, The Netherlands
| | | | | | - Guillermo León
- Instituto Clodomiro Picado, Universidad de Costa Rica, San Jose, Costa Rica
| | - Stuart Ainsworth
- Liverpool School of Tropical Medicine, Liverpool, UK
- Department of Infection Biology and Microbiomes, University of Liverpool, Liverpool, UK
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Borri J, Gutiérrez JM, Knudsen C, Habib AG, Goldstein M, Tuttle A. Landscape of toxin-neutralizing therapeutics for snakebite envenoming (2015-2022): Setting the stage for an R&D agenda. PLoS Negl Trop Dis 2024; 18:e0012052. [PMID: 38530781 PMCID: PMC10965046 DOI: 10.1371/journal.pntd.0012052] [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: 10/05/2023] [Accepted: 03/05/2024] [Indexed: 03/28/2024] Open
Abstract
BACKGROUND Progress in snakebite envenoming (SBE) therapeutics has suffered from a critical lack of data on the research and development (R&D) landscape. A database characterising this information would be a powerful tool for coordinating and accelerating SBE R&D. To address this need, we aimed to identify and categorise all active investigational candidates in development for SBE and all available or marketed products. METHODOLOGY/PRINCIPAL FINDINGS In this landscape study, publicly available data and literature were reviewed to canvas the state of the SBE therapeutics market and research pipeline by identifying, characterising, and validating all investigational drug and biologic candidates with direct action on snake venom toxins, and all products available or marketed from 2015 to 2022. We identified 127 marketed products and 196 candidates in the pipeline, describing a very homogenous market of similar but geographically bespoke products and a diverse but immature pipeline, as most investigational candidates are at an early stage of development, with only eight candidates in clinical development. CONCLUSIONS/SIGNIFICANCE Further investment and research is needed to address the shortfalls in products already on the market and to accelerate R&D for new therapeutics. This should be accompanied by efforts to converge on shared priorities and reshape the current SBE R&D ecosystem to ensure translation of innovation and access.
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Affiliation(s)
- Juliette Borri
- Policy Cures Research, Sydney, New South Wales, Australia
| | - José María Gutiérrez
- Instituto Clodomiro Picado, Facultad de Microbiología, Universidad de Costa Rica, San José, Costa Rica
| | | | - Abdulrazaq G. Habib
- Infectious and Tropical Diseases Unit, Department of Medicine, Bayero University, Kano, Nigeria
| | - Maya Goldstein
- Policy Cures Research, Sydney, New South Wales, Australia
| | - Andrew Tuttle
- Policy Cures Research, Sydney, New South Wales, Australia
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Bhaumik S, Habib AG, Santra V. Strategic priorities for accelerating action to reduce the burden of snakebite. PLOS GLOBAL PUBLIC HEALTH 2024; 4:e0002866. [PMID: 38315692 PMCID: PMC10843099 DOI: 10.1371/journal.pgph.0002866] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2024]
Affiliation(s)
- Soumyadeep Bhaumik
- Injury Division, George Institute for Global Health, New Delhi, India
- Meta-research and Evidence Synthesis Unit, Health Systems Science, George Institute for Global Health, Sydney, Australia
| | - Abdulrazaq G. Habib
- Infectious Disease and Tropical Medicine Unit, Department of Medicine, College of Health Science, Bayero University, Kano, Nigeria
| | - Vishal Santra
- Society for Nature Conservation, Research and Community Engagement (CONCERN), Nalikul, Hooghly, West Bengal, India
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Nyarko E, Ameho EK, Iddi S, Asiedu L. Challenges associated with the availability, accessibility, and use of antivenoms for treating snakebite envenoming in Ghana: A MaxDiff experiment design. Toxicon 2024; 238:107594. [PMID: 38191031 DOI: 10.1016/j.toxicon.2023.107594] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2023] [Revised: 12/20/2023] [Accepted: 12/30/2023] [Indexed: 01/10/2024]
Abstract
Successful snakebite envenoming (SBE) treatment requires safe, effective, and quality-assured antivenom products specifically tailored to combat endemic venomous snake species. This study aims to identify the challenges associated with the availability, accessibility, and use of antivenoms for treating SBE. The data for this study were obtained from a cross-sectional study involving healthcare workers from two districts (namely Afram Plains North and Afram Plains South) in the Eastern Region of Ghana. Through the MaxDiff design methodology, we quantify the challenges associated with the availability, accessibility, and use of antivenoms. Responses from a simple random sample of 203 healthcare workers were included in this study. Participants identified the high cost of antivenoms as the most challenging factor that limits the availability, accessibility, and use of antivenoms for treating SBE. Other important challenges were the lack of access to effective antivenoms in remote areas when needed and the increased use of unorthodox and harmful practices, followed by resort to unorthodox and harmful practices and the lack of effective antivenoms to address envenoming from local species in some instances. However, poor outcomes from using substandard antivenoms, stock-outs, inadequate number of manufacturers, and the resort to substandard, cheap, and harmful antivenoms were traded off. Also, poor utilization of antivenoms, suboptimal utilization of antivenoms (low quality, under-dose), use of ineffective, substandard antivenoms, and flooding of the market with products that have not been evaluated thoroughly were underscored. Our findings provide essential data to guide discussions on barriers to the availability, accessibility, and use of antivenoms for treating SBE to improve the supply of antivenoms, enhance the effectiveness of snakebite treatment, and improve patient care quality in Ghana. Multi-component strategies are needed to address the challenges identified, such as intensified advocacy, ongoing education and community engagement, healthcare worker training, and leveraging institutional and governance structures.
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Affiliation(s)
- Eric Nyarko
- Department of Statistics and Actuarial Science, School of Physical and Mathematical Sciences, University of Ghana, Box LG 115, Legon, Accra, Ghana.
| | - Ebenezer Kwesi Ameho
- Department of Statistics and Actuarial Science, School of Physical and Mathematical Sciences, University of Ghana, Box LG 115, Legon, Accra, Ghana
| | - Samuel Iddi
- Department of Statistics and Actuarial Science, School of Physical and Mathematical Sciences, University of Ghana, Box LG 115, Legon, Accra, Ghana
| | - Louis Asiedu
- Department of Statistics and Actuarial Science, School of Physical and Mathematical Sciences, University of Ghana, Box LG 115, Legon, Accra, Ghana
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McFarlane LO, Pukala TL. Proteomic Investigation of Cape Cobra ( Naja nivea) Venom Reveals First Evidence of Quaternary Protein Structures. Toxins (Basel) 2024; 16:63. [PMID: 38393141 PMCID: PMC10892407 DOI: 10.3390/toxins16020063] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2023] [Revised: 01/10/2024] [Accepted: 01/19/2024] [Indexed: 02/25/2024] Open
Abstract
Naja nivea (N. nivea) is classed as a category one snake by the World Health Organization since its envenomation causes high levels of mortality and disability annually. Despite this, there has been little research into the venom composition of N. nivea, with only one full venom proteome published to date. Our current study separated N. nivea venom using size exclusion chromatography before utilizing a traditional bottom-up proteomics approach to unravel the composition of the venom proteome. As expected by its clinical presentation, N. nivea venom was found to consist mainly of neurotoxins, with three-finger toxins (3FTx), making up 76.01% of the total venom proteome. Additionally, cysteine-rich secretory proteins (CRISPs), vespryns (VESPs), cobra venom factors (CVFs), 5'-nucleotidases (5'NUCs), nerve growth factors (NGFs), phospholipase A2s (PLA2), acetylcholinesterases (AChEs), Kunitz-type serine protease inhibitor (KUN), phosphodiesterases (PDEs), L-amino acid oxidases (LAAOs), hydrolases (HYDs), snake venom metalloproteinases (SVMPs), and snake venom serine protease (SVSP) toxins were also identified in decreasing order of abundance. Interestingly, contrary to previous reports, we find PLA2 toxins in N. nivea venom. This highlights the importance of repeatedly profiling the venom of the same species to account for intra-species variation. Additionally, we report the first evidence of covalent protein complexes in N. nivea venom, which likely contribute to the potency of this venom.
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Affiliation(s)
| | - Tara L. Pukala
- Department of Chemistry, The University of Adelaide, Adelaide 5005, Australia;
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Thumtecho S, Burlet NJ, Ljungars A, Laustsen AH. Towards better antivenoms: navigating the road to new types of snakebite envenoming therapies. J Venom Anim Toxins Incl Trop Dis 2023; 29:e20230057. [PMID: 38116472 PMCID: PMC10729942 DOI: 10.1590/1678-9199-jvatitd-2023-0057] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2023] [Accepted: 12/01/2023] [Indexed: 12/21/2023] Open
Abstract
Snakebite envenoming is a significant global health challenge, and for over a century, traditional plasma-derived antivenoms from hyperimmunized animals have been the primary treatment against this infliction. However, these antivenoms have several inherent limitations, including the risk of causing adverse reactions when administered to patients, batch-to-batch variation, and high production costs. To address these issues and improve treatment outcomes, the development of new types of antivenoms is crucial. During this development, key aspects such as improved clinical efficacy, enhanced safety profiles, and greater affordability should be in focus. To achieve these goals, modern biotechnological methods can be applied to the discovery and development of therapeutic agents that can neutralize medically important toxins from multiple snake species. This review highlights some of these agents, including monoclonal antibodies, nanobodies, and selected small molecules, that can achieve broad toxin neutralization, have favorable safety profiles, and can be produced on a large scale with standardized manufacturing processes. Considering the inherent strengths and limitations related to the pharmacokinetics of these different agents, a combination of them might be beneficial in the development of new types of antivenom products with improved therapeutic properties. While the implementation of new therapies requires time, it is foreseeable that the application of biotechnological advancements represents a promising trajectory toward the development of improved therapies for snakebite envenoming. As research and development continue to advance, these new products could emerge as the mainstay treatment in the future.
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Affiliation(s)
- Suthimon Thumtecho
- Division of Toxicology, Department of Medicine, Chulalongkorn University, King Chulalongkorn Memorial Hospital, the Thai Red Cross Society, Bangkok, Thailand
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Nick J. Burlet
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Anne Ljungars
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Andreas H. Laustsen
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kongens Lyngby, Denmark
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Werner RM, Soffa AN. Considerations for the development of a field-based medical device for the administration of adjunctive therapies for snakebite envenoming. Toxicon X 2023; 20:100169. [PMID: 37661997 PMCID: PMC10474190 DOI: 10.1016/j.toxcx.2023.100169] [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: 05/31/2023] [Revised: 07/27/2023] [Accepted: 08/12/2023] [Indexed: 09/05/2023] Open
Abstract
The timely administration of antivenom is the most effective method currently available to reduce the burden of snakebite envenoming (SBE), a neglected tropical disease that most often affects rural agricultural global populations. There is increasing interest in the development of adjunctive small molecule and biologic therapeutics that target the most problematic venom components to bridge the time-gap between initial SBE and the administration antivenom. Unique combinations of these therapeutics could provide relief from the toxic effects of regional groupings of medically relevant snake species. The application a PRISMA/PICO literature search methodology demonstrated an increasing interest in the rapid administration of therapies to improve patient symptoms and outcomes after SBE. Advice from expert interviews and considerations regarding the potential routes of therapy administration, anatomical bite location, and species-specific venom delivery have provided a framework to identify ideal metrics and potential hurdles for the development of a field-based medical device that could be used immediately after SBE to deliver adjunctive therapies. The use of subcutaneous (SC) or intramuscular (IM) injection were identified as potential routes of administration of both small molecule and biologic therapies. The development of a field-based medical device for the delivery of adjunctive SBE therapies presents unique challenges that will require a collaborative and transdisciplinary approach to be successful.
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10
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Chippaux JP, Ntone R, Benhammou D, Madec Y, Noël G, Perilhou A, Karl F, Amta P, Sanchez M, Matchim L, Clauteaux P, Eteki L, Ndifon M, Boum Y, Nkwescheu AS, Taieb F. Real life condition evaluation of Inoserp PAN-AFRICA antivenom effectiveness in Cameroon. PLoS Negl Trop Dis 2023; 17:e0011707. [PMID: 37939111 PMCID: PMC10659212 DOI: 10.1371/journal.pntd.0011707] [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: 12/20/2022] [Revised: 11/20/2023] [Accepted: 10/09/2023] [Indexed: 11/10/2023] Open
Abstract
BACKGROUND Snakebites is a serious public health issue but remains a neglected tropical disease. Data on antivenom effectiveness are urgently needed in Africa. We assessed effectiveness of Inoserp PAN-AFRICA (IPA), the recommended antivenom available in Cameroon. METHODOLOGY/PRINCIPAL FINDINGS We enrolled 447 patients presenting with snakebite in 14 health facilities across Cameroon. At presentation, cytotoxicity, coagulation troubles and neurotoxicity were graded. We administered two to four vials of antivenom to patients based on hemotoxic or neurotoxic signs. We renewed antivenom administration to patients with persistence of bleedings or neurotoxicity 2 hours after each injection. We defined early improvement as a reduction of the grade of envenomation symptoms 2 hours after first injection. Medium-term effectiveness was investigated looking at disappearance of symptoms during hospitalization. After hospital discharge, a home visit was planned to assess long-term outcomes. Between October 2019 and May 2021, we enrolled 447 (93.7%), including 72% from the savannah regions. The median [IQR] age was 25 [14-40]. Envenomation was diagnosed in 369 (82.6%) participants. The antivenom was administered to 356 patients (96.5%) of whom 256 (71.9%) received one administration. Among these patients, cytotoxic symptoms were observed in 336 (94.4%) participants, coagulation disorders in 234 (65.7%) participants and neurotoxicity in 23 (6.5%) participants. Two hours after the first administration of antivenom, we observed a decrease in coagulation disorders or neurotoxicity in 75.2% and 39.1% of patients, respectively. Complete cessation of bleedings and neurotoxicity occurred in 96% and 93% of patients within 24 hours, respectively. Sequelae have been observed in 9 (3%) patients at the home visit 15 days after hospital admission and 11 (3%) died including one before antivenom injection. CONCLUSIONS/SIGNIFICANCE We confirmed good effectiveness of the IPA and highlighted the rapid improvement in bleeding or neurotoxicity after the first administration. Sequential administrations of low doses of antivenom, rigorously assessed at short intervals for an eventual renewal, can preserve patient safety and save antivenom. TRIAL REGISTRATION NCT03326492.
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Affiliation(s)
- Jean-Philippe Chippaux
- Université Paris Cité, Institut de Recherche pour le développement, MERIT, Paris, France
- Institut Pasteur, Université Paris Cité, Centre de Recherche Translationnelle, Paris, France
| | | | - David Benhammou
- Institut Pasteur, Université Paris Cité, Emerging Diseases Epidemiology unit, Paris, France
| | - Yoann Madec
- Institut Pasteur, Université Paris Cité, Emerging Diseases Epidemiology unit, Paris, France
| | - Gaëlle Noël
- Institut Pasteur, Université Paris Cité, Centre de Recherche Translationnelle, Paris, France
| | - Anais Perilhou
- Institut Pasteur, Université Paris Cité, Centre de Recherche Translationnelle, Paris, France
| | - Fai Karl
- Epicentre Yaoundé, Yaoundé, Cameroon
| | | | - Marie Sanchez
- Institut Pasteur, Université Paris Cité, Data management core facility, Paris, France
| | | | - Pedro Clauteaux
- Institut Pasteur, Université Paris Cité, Centre de Recherche Translationnelle, Paris, France
| | | | | | - Yap Boum
- Epicentre Yaoundé, Yaoundé, Cameroon
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Warrell DA, Williams DJ. Clinical aspects of snakebite envenoming and its treatment in low-resource settings. Lancet 2023; 401:1382-1398. [PMID: 36931290 DOI: 10.1016/s0140-6736(23)00002-8] [Citation(s) in RCA: 18] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/15/2022] [Revised: 11/26/2022] [Accepted: 12/18/2022] [Indexed: 03/16/2023]
Abstract
There is increasing recognition of the public health importance of snakebite envenoming. Worldwide annual incidence is likely to be 5 million bites, with mortality exceeding 150 000 deaths, and the resulting physical and psychological morbidity leads to substantial social and economic repercussions. Prevention through community education by trained health workers is the most effective and economically viable strategy for reducing risk of bites and envenoming. Clinical challenges to effective treatment are most substantial in rural areas of low-resource settings, where snakebites are most common. Classic skills of history taking, physical examination, and use of affordable point-of-care tests should be followed by monitoring of evolving local and systemic envenoming. Despite the profusion of new ideas for interventions, hyperimmune equine or ovine plasma-derived antivenoms remain the only specific treatment for snakebite envenoming. The enormous interspecies and intraspecies complexity and diversity of snake venoms, revealed by modern venomics, demands a radical redesign of many current antivenoms.
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Affiliation(s)
- David A Warrell
- Nuffield Department of Clinical Medicine, University of Oxford, Oxford, UK; Experimental Medicine Division, John Radcliffe Hospital, Headington, UK.
| | - David J Williams
- Regulation and Prequalification Department, World Health Organization, Geneva, Switzerland
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Husain Z, Wicaksono AC, Renault A, Md Zhahir SS, Ismail AK. A case of fatal envenomation by a captive puff adder (Bitis arietans) in Malaysia. Toxicon 2023; 224:107023. [PMID: 36640813 DOI: 10.1016/j.toxicon.2023.107023] [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: 11/15/2022] [Revised: 01/01/2023] [Accepted: 01/05/2023] [Indexed: 01/13/2023]
Abstract
The Puff Adder (Bitis arietans) is a viper native to Africa and the Middle East. Envenomation by this species often requires the administration of appropriate antivenom in order to achieve a favorable outcome. A patient was bitten in both hands by a captive B. arietans presented to a teaching hospital in Malaysia. The patient developed painful progressive swelling on both limbs that extended to the chest, hypotension, hypokalemia with worsening anemia, thrombocytopenia, coagulopathy, and severe metabolic acidosis. The patient was managed supportively while waiting for the appropriate antivenom, Antivipmyn-Africa, from the Singapore Zoo. The patient developed cardiorespiratory arrest twice and did not recover from the second. The patient was pronounced dead 23 hours post-incident. The local unavailability of the appropriate antivenom may be the most important factor that contributed to the patient's death. There is also a need to amend the Malaysian Wildlife Act in order to prevent such cases from recurring.
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Affiliation(s)
- Zulfahimi Husain
- Department of Emergency Medicine, Faculty of Medicine, University Kebangsaan Malaysia, Jalan Yaacob Latif, Bandar Tun Razak, Kuala Lumpur, Malaysia
| | - Aji Caesar Wicaksono
- Department of Emergency Medicine, Faculty of Medicine, University Kebangsaan Malaysia, Jalan Yaacob Latif, Bandar Tun Razak, Kuala Lumpur, Malaysia
| | - Asyhok Renault
- Department of Emergency Medicine, Faculty of Medicine, University Kebangsaan Malaysia, Jalan Yaacob Latif, Bandar Tun Razak, Kuala Lumpur, Malaysia
| | - Siti Sarah Md Zhahir
- Department of Emergency Medicine, Faculty of Medicine, University Kebangsaan Malaysia, Jalan Yaacob Latif, Bandar Tun Razak, Kuala Lumpur, Malaysia
| | - Ahmad Khaldun Ismail
- Department of Emergency Medicine, Faculty of Medicine, University Kebangsaan Malaysia, Jalan Yaacob Latif, Bandar Tun Razak, Kuala Lumpur, Malaysia.
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Lermer A, Marks CJ, Kellermann TA. Snakebite in South Africa: A retrospective review May 2015-June 2020. Toxicon 2023; 224:107031. [PMID: 36669533 DOI: 10.1016/j.toxicon.2023.107031] [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: 10/27/2022] [Revised: 01/15/2023] [Accepted: 01/16/2023] [Indexed: 01/19/2023]
Abstract
Snakebite envenoming in Sub-Saharan Africa present a significant public health problem. An investigation into how often species responsible for envenomation were correctly identified, as well as which venomous species caused the most frequent and problematic envenomation symptomatology were conducted to establish severity of this problem from a South African context. Descriptive statistics were used to quantitatively describe the variables in snakebite related Telelog call records reported to the Poison Information Helpline of the Western Cape (PIHWC) over a five-year period. A total of 1411 snakebite related calls were received. In 44% of all snakebite calls the bite was inflicted by an unidentified snake specie. The most snakebites occurred during the summer months from December-March. The most bites occurred in males (20-39 years). The incidence of snakebite in South Africa was 2.39 per 100 000 population, with the highest incidence of snakebite in North-West province of South Africa. In sub-Saharan Africa there is a major underestimation of the incidence of snakebite due to under reporting and absence of physical attendance to health care facilities. The PIHWC provides an invaluable service in assisting and in-forming medical personnel and the public on the management of snakebites. Data collected by centers provides a source of information on the prevalence of snakebites and medically important species that research should be aimed towards.
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Affiliation(s)
- A Lermer
- Division of Clinical Pharmacology, Department of Medicine, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, Western Cape, South Africa.
| | - C J Marks
- Division of Clinical Pharmacology, Department of Medicine, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, Western Cape, South Africa
| | - T A Kellermann
- Division of Clinical Pharmacology, Department of Medicine, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, Western Cape, South Africa
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14
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Bala AA, Mohammed M, Umar S, Ungogo MA, Al-Kassim Hassan M, Abdussalam US, Ahmad MH, Ishaq DU, Mana D, Sha'aban A, Jatau AI, Jibril M, Kurfi B, Raji I, Ringim AS, Gulma K, Malami S, Michael GC, Chedi BAZ. Pre-clinical efficacy of African medicinal plants used in the treatment of snakebite envenoming: A systematic review. Toxicon 2023; 224:107035. [PMID: 36706926 DOI: 10.1016/j.toxicon.2023.107035] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2022] [Revised: 01/19/2023] [Accepted: 01/19/2023] [Indexed: 01/26/2023]
Abstract
The World Health Organization has listed Snakebite Envenoming (SBE) as a priority neglected tropical disease, with a worldwide annual snakebite affecting 5.4 million people and injuring 2.7 million lives. In many parts of rural areas of Africa and Asia, medicinal plants have been used as alternatives to conventional antisnake venom (ASV) due in part to inaccessibility to hospitals. Systemic reviews (SR) of laboratory-based preclinical studies play an essential role in drug discovery. We conducted an SR to evaluate the relationship between interventional medicinal plants and their observed effects on venom-induced experiments. This SR was reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses. The Modified collaborative approach to meta-analysis and review of animal data from experimental studies (CAMARADES) and SYRCLE's risk of bias tools were used to appraise the included studies. Data were searched online in Medline via PubMed, Embase via OVID, and Scopus. Studies reporting in vivo and in vitro pharmacological activities of African medicinal plants/extracts/constituents against venom-induced pathologies were identified and included for screening. Data from the included studies were extracted and synthesized. Ten studies reported statistically significant percentage protection (40-100%) of animals against venom-induced lethality compared with control groups that received no medicinal plant intervention. Sixteen studies reported significant effects (p ≤ 0.05) against venom-induced pathologies compared with the control group; these include hemolytic, histopathologic, necrotic, and anti-enzymatic effects. The plant family Fabaceae has the highest number of studies reporting its efficacy, followed by Annonaceae, Malvaceae, Combretaceae, Sterculiaceae, and Olacaceae. Some African medicinal plants are preclinically effective against venom-induced lethality, hematotoxicity, and cytotoxicity. The evidence was extracted from three in vitro studies, nine in vivo studies, and five studies that combined both in vivo and in vitro models. The effective plants belong to the Fabaceae family, followed by Malvaceae, and Annonaceae.
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Affiliation(s)
- Auwal A Bala
- Department of Pharmacology, College of Medicine and Health Sciences, Federal University Dutse, Nigeria; Department of Pharmacology and Therapeutics, Bayero University, Kano, Nigeria.
| | - Mustapha Mohammed
- School of Pharmaceutical Sciences, Universiti Sains Malaysia, Penang, Pulau Pinang, Malaysia; Department of Clinical Pharmacy and Pharmacy Practice, Faculty of Pharmaceutical Sciences, Ahmadu Bello University, Zaria, Kaduna, Nigeria
| | - Saifullahi Umar
- Department of Pharmacognosy and Herbal Medicine, Faculty of Pharmaceutical Sciences, College of Natural and Pharmaceutical Sciences, Bayero University Kano, Nigeria
| | - Marzuq A Ungogo
- Department of Veterinary Pharmacology and Toxicology, Faculty of Veterinary Medicine, Ahmadu Bello University, Zaria, 810107, Kaduna State, Nigeria; Roslin Institute, Royal (Dick) School of Veterinary Studies, University of Edinburgh, UK
| | | | - Umar S Abdussalam
- Department of Pharmacology and Therapeutics, Bayero University, Kano, Nigeria
| | - Mubarak Hussaini Ahmad
- Department of Pharmacology and Therapeutics, Ahmadu Bello University, Zaria, Nigeria; Department of Pharmacology and Therapeutics, Faculty of Pharmaceutical Sciences, Capital City University, Kano State, Nigeria
| | - Daha U Ishaq
- Department of Biochemistry, Faculty of Basic Medical Sciences, College of Health Science,Bayero University, Kano, Nigeria; Center for Mitochondrial Biology & Medicine, Xi'an Jiaotong University (XJTU), Xi'an, China
| | - Dillos Mana
- Department of Community Medicine and Primary Healthcare, Bingham University, Abuja, Nigeria
| | - Abubakar Sha'aban
- School of Medicine, Cardiff University, Heath Park, Cardiff, CF14 4YS, UK
| | - Abubakar I Jatau
- School of Pharmacy and Pharmacology, University of Tasmania, Hobart, Australia
| | - Murtala Jibril
- Department of Pharmacology and Therapeutics, Bayero University, Kano, Nigeria
| | - Binta Kurfi
- Department of Biochemistry, Faculty of Basic Medical Sciences, College of Health Science,Bayero University, Kano, Nigeria
| | - Ismaila Raji
- Department of Pharmacology, College of Medicine and Health Sciences, Federal University Dutse, Nigeria
| | - Abubakar S Ringim
- Morgan State University, Patuxent Environmental and Aquatic Research Laboratory, Maryland, USA; Department of Biological Sciences, Federal University Dutse, Jigawa State, Nigeria
| | - Kabiru Gulma
- School of Global Health and Bioethics, Euclid University, Gambia
| | - Sani Malami
- Department of Pharmacology and Therapeutics, Bayero University, Kano, Nigeria
| | - Godpower C Michael
- Department of Family Medicine, Aminu Kano Teaching Hospital, Kano, Nigeria
| | - Basheer A Z Chedi
- Department of Pharmacology and Therapeutics, Bayero University, Kano, Nigeria; Venom-Antivenom Research Project (VASP) and Nigeria- Snakebite Research and Intervention Centre(NSRIC), Nigeria
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15
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Palasuberniam P, Tan KY, Chan YW, Blanco FB, Tan CH. Decomplexation proteomic analysis and purity assessment of a biologic for snakebite envenoming: Philippine Cobra Antivenom. Trans R Soc Trop Med Hyg 2023:6972591. [PMID: 36611268 DOI: 10.1093/trstmh/trac125] [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: 05/09/2022] [Revised: 11/02/2022] [Accepted: 12/10/2022] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND Philippine Cobra Antivenom (PCAV) is the only snake antivenom manufactured in the Philippines. It is used clinically to treat envenoming caused by the Philippine Spitting Cobra (Naja philippinensis). While PCAV is effective pharmacologically, it is crucial to ensure the safety profile of this biologic that is derived from animal plasma. METHODS This study examined the composition purity of PCAV through a decomplexation proteomic approach, applying size-exclusion chromatography (SEC), sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and tandem mass spectrometry liquid chromatography-tandem mass spectrometry (LC-MS/MS). RESULTS SDS-PAGE and SEC showed that the major protein in PCAV (constituting ∼80% of total proteins) is approximately 110 kDa, consistent with the F(ab')2 molecule. This protein is reducible into two subunits suggestive of the light and heavy chains of immunoglobulin G. LC-MS/MS further identified the proteins as equine immunoglobulins, representing the key therapeutic ingredient of this biologic product. However, protein impurities, including fibrinogens, alpha-2-macroglobulins, albumin, transferrin, fibronectin and plasminogen, were detected at ∼20% of the total antivenom proteins, unveiling a concern for hypersensitivity reactions. CONCLUSIONS Together, the findings show that PCAV contains a favorable content of F(ab')2 for neutralization, while the antibody purification process awaits improvement to minimize the presence of protein impurities.
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Affiliation(s)
- Praneetha Palasuberniam
- Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, University Malaysia Sabah, 88400 Kota Kinabalu, Sabah, Malaysia.,Venom Research & Toxicology Laboratory, Department of Pharmacology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Kae Yi Tan
- Protein and Interactomics Laboratory, Department of Molecular Medicine, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Yi Wei Chan
- Department of Emergency Medicine, Ospital ng Muntinlupa, 1781 Muntinlupa, Manila, Philippines
| | - Francis Bonn Blanco
- Department of Emergency Medicine, Ospital ng Muntinlupa, 1781 Muntinlupa, Manila, Philippines.,Department of Internal Medicine, Davao Medical School Foundation Hospital, 8000 Davao City, Philippines
| | - Choo Hock Tan
- Venom Research & Toxicology Laboratory, Department of Pharmacology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
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16
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Snakebite envenoming at MSF: A decade of clinical challenges and antivenom access issues. Toxicon X 2022; 17:100146. [PMID: 36619819 PMCID: PMC9813776 DOI: 10.1016/j.toxcx.2022.100146] [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: 12/09/2022] [Accepted: 12/19/2022] [Indexed: 12/24/2022] Open
Abstract
The medical humanitarian organization Médecins Sans Frontières (MSF) provides medical care in more than 70 countries and admits more than 7000 cases of snakebite in its facilities each year. We describe our activities against snakebite in three African countries: Central African Republic, South Sudan and Ethiopia, in which different models of care have been developed. A standard protocol using two different antivenoms depending on the patient's syndrome has been introduced, and a simple blood coagulation test is performed to detect venom-induced coagulopathy. Other services, including surgery for necrotizing wounds, are offered in the facilities where MSF admits a large number of snakebite patients. All services, including provision of antivenom, are offered free-of-charge in MSF-supported facilities. Community-based activities focusing on preventive measures and prompt transport to hospital have been developed in a few MSF projects. The provision of quality care and treatment, including effective antivenoms, without out-of-pocket payments by the patients, probably explains why MSF has admitted an increasing number of snakebite victims over the last years. This model requires significant resources and monitoring, including regular training of healthcare workers on treatment protocols and a considerable budget for antivenom procurement.
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17
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Tan CH, Wong KY, Huang LK, Tan KY, Tan NH, Wu WG. Snake Venomics and Antivenomics of Cape Cobra ( Naja nivea) from South Africa: Insights into Venom Toxicity and Cross-Neutralization Activity. Toxins (Basel) 2022; 14:toxins14120860. [PMID: 36548757 PMCID: PMC9783313 DOI: 10.3390/toxins14120860] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2022] [Revised: 11/24/2022] [Accepted: 11/30/2022] [Indexed: 12/14/2022] Open
Abstract
Naja nivea (Cape Cobra) is endemic to southern Africa. Envenoming by N. nivea is neurotoxic, resulting in fatal paralysis. Its venom composition, however, has not been studied in depth, and specific antivenoms against it remain limited in supply. Applying a protein decomplexation approach, this study unveiled the venom proteome of N. nivea from South Africa. The major components in the venom are cytotoxins/cardiotoxins (~75.6% of total venom proteins) and alpha-neurotoxins (~7.4%), which belong to the three-finger toxin family. Intriguingly, phospholipase A2 (PLA2) was undetected-this is a unique venom phenotype increasingly recognized in the African cobras of the Uraeus subgenus. The work further showed that VINS African Polyvalent Antivenom (VAPAV) exhibited cross-reactivity toward the venom and immunorecognized its toxin fractions. In mice, VAPAV was moderately efficacious in cross-neutralizing the venom lethality with a potency of 0.51 mg/mL (amount of venom completely neutralized per milliliter of antivenom). In the challenge-rescue model, VAPAV prevented death in 75% of experimentally envenomed mice, with slow recovery from neurotoxicity up to 24 h. The finding suggests the potential para-specific utility of VAPAV for N. nivea envenoming, although a higher dose or repeated administration of the antivenom may be required to fully reverse the neurotoxic effect of the venom.
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Affiliation(s)
- Choo Hock Tan
- Venom Research and Toxicology Laboratory, Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia
- Institute of Bioinformatics and Structural Biology, Department of Life Science, National Tsing Hua University, Hsinchu 300044, Taiwan
- Correspondence: or
| | - Kin Ying Wong
- Venom Research and Toxicology Laboratory, Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia
- Institute of Bioinformatics and Structural Biology, Department of Life Science, National Tsing Hua University, Hsinchu 300044, Taiwan
| | - Li-Kun Huang
- Institute of Bioinformatics and Structural Biology, Department of Life Science, National Tsing Hua University, Hsinchu 300044, Taiwan
| | - Kae Yi Tan
- Protein and Interactomics Laboratory, Department of Molecular Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia
| | - Nget Hong Tan
- Protein and Interactomics Laboratory, Department of Molecular Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia
| | - Wen-Guey Wu
- Institute of Bioinformatics and Structural Biology, Department of Life Science, National Tsing Hua University, Hsinchu 300044, Taiwan
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Aron MB, Kachimanga C, Kreuels B, Mailosi B, Sambani C, Matanje BL, Blessmann J, Chunga M, Momba G, Ndarama E, Kambalame DM, Connolly E, Rosenthal A, Munyaneza F. Health care workers' knowledge on identification, management and treatment of snakebite cases in rural Malawi: A descriptive study. PLoS Negl Trop Dis 2022; 16:e0010841. [PMID: 36409666 PMCID: PMC9678285 DOI: 10.1371/journal.pntd.0010841] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Accepted: 09/23/2022] [Indexed: 11/22/2022] Open
Abstract
Snakebite envenoming remains a public health threat in many African countries, including Malawi. However, there is a shortage of literature on the knowledge of Health Care Workers (HCWs) and the prevalence of snakebite cases in Malawi. We interviewed HCWs in Neno District to assess their knowledge of snake identification and management of snakebites. We further reviewed patient registers from 2018 to 2021 in all 15 health facilities in the district. We used descriptive statistics to characterize the survey population, knowledge, snake antivenom (SAV) administration, and snake identification. Using "shapefiles" from Open Street Maps, we mapped villages with snakebite cases. Of the 105 HCWs interviewed, 58% were males, and 60% had worked for less than five years. The majority (n = 93, 89%) reported that snakebite envenoming was a problem in the district. Among the clinicians, 42% said they had prescribed SAV previously, while among nurses, only 26% had ever administered SAV. There were discrepancies among clinicians regarding the dosing of snake antivenom. Significant gaps in knowledge also existed regarding snake identification. While two-thirds of HCWs could correctly name and identify venomous snake species, most (> 90%) failed for non-venomous snakes. Most (n = 100, 95%) reported that snakebite victims visit traditional healers more than the hospital. Between 2018 and 2021, the Neno District registered 185 snakebites with a yearly average of 36 cases per 100,000 population. Fifty-two percent (n = 97) were treated as an inpatient; of these cases, 72% were discharged in less than three days, and two died. More snakebite cases were recorded in the eastern part of the district. Significant knowledge gaps exist among HCWs in Neno regarding prescription and administration of SAV and snake identification, which likely challenges the quality of services offered to snakebite victims.
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Affiliation(s)
- Moses Banda Aron
- Partners In Health / Abwenzi Pa Za Umoyo, Neno, Malawi
- Research Group Snakebite Envenoming, Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany
- * E-mail:
| | | | - Benno Kreuels
- Research Group Snakebite Envenoming, Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany
- Section for Tropical Medicine, I. Department of Medicine, University Medical Center Hamburg, Germany
| | | | - Clara Sambani
- Department of Research, Ministry of Health, Lilongwe, Malawi
| | | | - Joerg Blessmann
- Research Group Snakebite Envenoming, Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany
| | - Mwayi Chunga
- Partners In Health / Abwenzi Pa Za Umoyo, Neno, Malawi
| | - Grace Momba
- Neno District Health Office, Ministry of Health, Neno, Malawi
| | - Enoch Ndarama
- Neno District Health Office, Ministry of Health, Neno, Malawi
| | | | - Emilia Connolly
- Partners In Health / Abwenzi Pa Za Umoyo, Neno, Malawi
- Division of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States of America
- Division of Hospital Medicine, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio, United States of America
| | - Anat Rosenthal
- Department of Health Policy and Management, Ben-Gurion University of the Negev, Beersheba, Israel
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Offor BC, Muller B, Piater LA. A Review of the Proteomic Profiling of African Viperidae and Elapidae Snake Venoms and Their Antivenom Neutralisation. Toxins (Basel) 2022; 14:toxins14110723. [PMID: 36355973 PMCID: PMC9694588 DOI: 10.3390/toxins14110723] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2022] [Revised: 10/17/2022] [Accepted: 10/20/2022] [Indexed: 11/06/2022] Open
Abstract
Snakebite envenoming is a neglected tropical disease (NTD) that results from the injection of snake venom of a venomous snake into animals and humans. In Africa (mainly in sub-Saharan Africa), over 100,000 envenomings and over 10,000 deaths per annum from snakebite have been reported. Difficulties in snakebite prevention and antivenom treatment are believed to result from a lack of epidemiological data and underestimated figures on snakebite envenoming-related morbidity and mortality. There are species- and genus-specific variations associated with snake venoms in Africa and across the globe. These variations contribute massively to diverse differences in venom toxicity and pathogenicity that can undermine the efficacy of adopted antivenom therapies used in the treatment of snakebite envenoming. There is a need to profile all snake venom proteins of medically important venomous snakes endemic to Africa. This is anticipated to help in the development of safer and more effective antivenoms for the treatment of snakebite envenoming within the continent. In this review, the proteomes of 34 snake venoms from the most medically important snakes in Africa, namely the Viperidae and Elipdae, were extracted from the literature. The toxin families were grouped into dominant, secondary, minor, and others based on the abundance of the protein families in the venom proteomes. The Viperidae venom proteome was dominated by snake venom metalloproteinases (SVMPs-41%), snake venom serine proteases (SVSPs-16%), and phospholipase A2 (PLA2-17%) protein families, while three-finger toxins (3FTxs-66%) and PLA2s (16%) dominated those of the Elapidae. We further review the neutralisation of these snake venoms by selected antivenoms widely used within the African continent. The profiling of African snake venom proteomes will aid in the development of effective antivenom against snakebite envenoming and, additionally, could possibly reveal therapeutic applications of snake venom proteins.
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Affiliation(s)
- Benedict C. Offor
- Department of Biochemistry, Faculty of Science, University of Johannesburg, Auckland Park 2006, South Africa
| | - Beric Muller
- South Africa Venom Suppliers CC, Louis Trichardt 0920, South Africa
| | - Lizelle A. Piater
- Department of Biochemistry, Faculty of Science, University of Johannesburg, Auckland Park 2006, South Africa
- Correspondence: ; Tel.: +27-11-559-2403
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20
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Menzies SK, Litschka-Koen T, Edge RJ, Alsolaiss J, Crittenden E, Hall SR, Westhorpe A, Thomas B, Murray J, Shongwe N, Padidar S, Lalloo DG, Casewell NR, Pons J, Harrison RA. Two snakebite antivenoms have potential to reduce Eswatini's dependency upon a single, increasingly unavailable product: Results of preclinical efficacy testing. PLoS Negl Trop Dis 2022; 16:e0010496. [PMID: 36108067 PMCID: PMC9529146 DOI: 10.1371/journal.pntd.0010496] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Revised: 10/03/2022] [Accepted: 08/15/2022] [Indexed: 11/24/2022] Open
Abstract
BACKGROUND Snakebite is a major public health concern in Eswatini, where treatment relies upon one antivenom-SAIMR Polyvalent. Although effective in treating snakebite, SAIMR Polyvalent is difficult to source outside its manufacturing country (South Africa) and is dauntingly expensive. We compared the preclinical venom-neutralising efficacy of two alternative antivenoms with that of SAIMR Polyvalent against the lethal and tissue-destructive effects of venoms from five species of medically important snakes using in vivo murine assays. The test antivenoms were 'Panafrican' manufactured by Instituto Clodomiro Picado and 'PANAF' manufactured by Premium Serums & Vaccines. PRINCIPAL FINDINGS In vivo murine preclinical studies identified both test antivenoms were equally or more effective than SAIMR Polyvalent at neutralising lethal and tissue-destructive effects of Naja mossambica venom. Both test antivenoms were less effective than SAIMR Polyvalent at neutralising the lethal effects of Bitis arietans, Dendroaspis polylepis, Hemachatus haemachatus and Naja annulifera venoms, but similarly effective at neutralising tissue damage induced by B. arietans and H. haemachatus venoms. In vitro immunological assays identified that the titres and toxin-specificities of immunoglobulins (iGs) in the test antivenoms were comparable to that of SAIMR Polyvalent. Plasma clotting disturbances by H. haemachatus and N. mossambica were neutralised by the test antivenoms, whereas SAIMR Polyvalent failed to neutralise this bioactivity of N. mossambica venom. B. arietans SVMP activity was equally reduced by all three antivenoms, and H. haemachatus and N. mossambica PLA2 activities were neutralised by all three antivenoms. CONCLUSIONS While both Panafrican and PANAF antivenoms exhibited promising preclinical efficacies, both were less poly-specifically effective than SAIMR Polyvalent in these murine assays. The efficacy of these antivenoms against the lethal and tissue-destructive effects of N. mossambica venom, the most common biting species in Eswatini, identify that Panafrican and PANAF antivenoms offer effective alternatives to SAIMR Polyvalent for the treatment of snakebite in Eswatini, and potentially for neighbouring countries.
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Affiliation(s)
- Stefanie K. Menzies
- Centre for Snakebite Research and Interventions, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
- Centre for Drugs and Diagnostics, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Thea Litschka-Koen
- Eswatini Snakebite Research and Intervention Centre, Simunye, Eswatini
- Eswatini Antivenom Foundation, Simunye, Eswatini
| | - Rebecca J. Edge
- Centre for Snakebite Research and Interventions, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Jaffer Alsolaiss
- Centre for Snakebite Research and Interventions, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Edouard Crittenden
- Centre for Snakebite Research and Interventions, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Steven R. Hall
- Centre for Snakebite Research and Interventions, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Adam Westhorpe
- Centre for Snakebite Research and Interventions, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Brent Thomas
- Centre for Snakebite Research and Interventions, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - James Murray
- Eswatini Snakebite Research and Intervention Centre, Simunye, Eswatini
- Eswatini Antivenom Foundation, Simunye, Eswatini
| | - Nondusimo Shongwe
- Eswatini Snakebite Research and Intervention Centre, Simunye, Eswatini
- Eswatini Antivenom Foundation, Simunye, Eswatini
| | - Sara Padidar
- Eswatini Snakebite Research and Intervention Centre, Simunye, Eswatini
- Eswatini Antivenom Foundation, Simunye, Eswatini
- Department of Biological Sciences, University of Eswatini, Kwaluseni, Eswatini
| | - David G. Lalloo
- Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Nicholas R. Casewell
- Centre for Snakebite Research and Interventions, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
- Centre for Drugs and Diagnostics, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Jonathan Pons
- Eswatini Snakebite Research and Intervention Centre, Simunye, Eswatini
- Eswatini Antivenom Foundation, Simunye, Eswatini
| | - Robert A. Harrison
- Centre for Snakebite Research and Interventions, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
- Centre for Drugs and Diagnostics, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
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Computer-Aided Analysis of West Sub-Saharan Africa Snakes Venom towards the Design of Epitope-Based Poly-Specific Antivenoms. Toxins (Basel) 2022; 14:toxins14060418. [PMID: 35737079 PMCID: PMC9229730 DOI: 10.3390/toxins14060418] [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: 05/03/2022] [Revised: 06/10/2022] [Accepted: 06/16/2022] [Indexed: 02/01/2023] Open
Abstract
Snakebite envenomation is a neglected tropical disease that causes over 100,000 deaths each year. The only effective treatment consists of antivenoms derived from animal sera, but these have been deemed with highly variable potency and are usually inaccessible and too costly for victims. The production of antivenoms by venom-independent techniques, such as the immunization with multi-epitope constructs, could circumvent those drawbacks. Herein, we present a knowledge-based pipeline to prioritize potential epitopes of therapeutic relevance from toxins of medically important snakes in West Sub-Saharan Africa. It is mainly based on sequence conservation and protein structural features. The ultimately selected 41 epitopes originate from 11 out of 16 snake species considered of highest medical importance in the region and 3 out of 10 of those considered as secondary medical importance. Echis ocellatus, responsible for the highest casualties in the area, would be covered by 12 different epitopes. Remarkably, this pipeline is versatile and customizable for the analysis of snake venom sequences from any other region of the world.
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Menzies SK, Clare RH, Xie C, Westhorpe A, Hall SR, Edge RJ, Alsolaiss J, Crittenden E, Marriott AE, Harrison RA, Kool J, Casewell NR. In vitro and in vivo preclinical venom inhibition assays identify metalloproteinase inhibiting drugs as potential future treatments for snakebite envenoming by Dispholidus typus. Toxicon X 2022; 14:100118. [PMID: 35321116 PMCID: PMC8935517 DOI: 10.1016/j.toxcx.2022.100118] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2021] [Revised: 02/18/2022] [Accepted: 03/07/2022] [Indexed: 11/23/2022] Open
Abstract
Snakebite envenoming affects more than 250,000 people annually in sub-Saharan Africa. Envenoming by Dispholidus typus (boomslang) results in venom-induced consumption coagulopathy (VICC), whereby highly abundant prothrombin-activating snake venom metalloproteinases (SVMPs) consume clotting factors and deplete fibrinogen. The only available treatment for D. typus envenoming is the monovalent SAIMR Boomslang antivenom. Treatment options are urgently required because this antivenom is often difficult to source and, at US$6000/vial, typically unaffordable for most snakebite patients. We therefore investigated the in vitro and in vivo preclinical efficacy of four SVMP inhibitors to neutralise the effects of D. typus venom; the matrix metalloproteinase inhibitors marimastat and prinomastat, and the metal chelators dimercaprol and DMPS. The venom of D. typus exhibited an SVMP-driven procoagulant phenotype in vitro. Marimastat and prinomastat demonstrated equipotent inhibition of the SVMP-mediated procoagulant activity of the venom in vitro, whereas dimercaprol and DMPS showed considerably lower potency. However, when tested in preclinical murine models of envenoming using mixed sex CD1 mice, DMPS and marimastat demonstrated partial protection against venom lethality, demonstrated by prolonged survival times of experimental animals, whereas dimercaprol and prinomastat failed to confer any protection at the doses tested. The preclinical results presented here demonstrate that DMPS and marimastat show potential as novel small molecule-based therapeutics for D. typus snakebite envenoming. These two drugs have been previously shown to be effective against Echis ocellatus VICC in preclinical models, and thus we conclude that marimastat and DMPS should be further explored as potentially valuable early intervention therapeutics to broadly treat VICC following snakebite envenoming in sub-Saharan Africa.
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Affiliation(s)
- Stefanie K. Menzies
- Centre for Snakebite Research and Interventions, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, England, UK
- Centre for Drugs and Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, England, UK
| | - Rachel H. Clare
- Centre for Snakebite Research and Interventions, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, England, UK
- Centre for Drugs and Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, England, UK
| | - Chunfang Xie
- Amsterdam Institute of Molecular and Life Sciences, Division of BioAnalytical Chemistry, Department of Chemistry and Pharmaceutical Sciences, Faculty of Science, Vrije Universiteit Amsterdam, De Boelelaan 1085, 1081HV, Amsterdam, the Netherlands
| | - Adam Westhorpe
- Centre for Snakebite Research and Interventions, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, England, UK
- Centre for Drugs and Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, England, UK
| | - Steven R. Hall
- Centre for Snakebite Research and Interventions, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, England, UK
- Centre for Drugs and Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, England, UK
| | - Rebecca J. Edge
- Centre for Snakebite Research and Interventions, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, England, UK
- Centre for Drugs and Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, England, UK
| | - Jaffer Alsolaiss
- Centre for Snakebite Research and Interventions, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, England, UK
- Centre for Drugs and Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, England, UK
| | - Edouard Crittenden
- Centre for Snakebite Research and Interventions, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, England, UK
- Centre for Drugs and Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, England, UK
| | - Amy E. Marriott
- Centre for Snakebite Research and Interventions, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, England, UK
- Centre for Drugs and Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, England, UK
| | - Robert A. Harrison
- Centre for Snakebite Research and Interventions, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, England, UK
- Centre for Drugs and Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, England, UK
| | - Jeroen Kool
- Amsterdam Institute of Molecular and Life Sciences, Division of BioAnalytical Chemistry, Department of Chemistry and Pharmaceutical Sciences, Faculty of Science, Vrije Universiteit Amsterdam, De Boelelaan 1085, 1081HV, Amsterdam, the Netherlands
| | - Nicholas R. Casewell
- Centre for Snakebite Research and Interventions, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, England, UK
- Centre for Drugs and Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, England, UK
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Larson PS, Ndemwa M, Thomas AF, Tamari N, Diela P, Changoma M, Mohamed A, Larson MC, Ketenci KC, Goto K, Kaneko S. Snakebite victim profiles and treatment-seeking behaviors in two regions of Kenya: results from a health demographic surveillance system. Trop Med Health 2022; 50:31. [PMID: 35488352 PMCID: PMC9052588 DOI: 10.1186/s41182-022-00421-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Accepted: 04/11/2022] [Indexed: 11/10/2022] Open
Abstract
INTRODUCTION Snakebites are a major cause of permanent injury and death among poor, rural populations in developing countries, including those in East Africa. This research characterizes snakebite incidence, risk factors, and subsequent health-seeking behaviors in two regions of Kenya using a mixed methods approach. METHODS As a part of regular activities of a health demographic surveillance system, household-level survey on snakebite incidence was conducted in two areas of Kenya: Kwale along the Kenyan Coast and Mbita on Lake Victoria. If someone in the home was reported to have been bitten in the 5 years previous to the visit, a survey instrument was administered. The survey gathered contextual information on the bite, treatment-seeking behavior and clinical manifestations. To obtain deeper, contextual information, respondents were also asked to narrate the bite incident, subsequent behavior and outcomes. RESULTS 8775 and 9206 households were surveyed in Kwale and Mbita, respectively. Out of these, 453 (5.17%) and 92 (1.00%) households reported that at least one person had been bitten by a snake in the past 5 years. Deaths from snakebites were rare (4.04%), but patterns of treatment seeking varied. Treatment at formal care facilities were sought for 50.8% and at traditional healers for 53.3%. 18.4% sought treatment from both sources. Victims who delayed receiving treatment from a formal facility were more likely to have consulted a traditional healer (OR 8.8995% CI [3.83, 20.64]). Delays in treatment seeking were associated with significantly increased odds of having a severe outcome, including death, paralysis or loss of consciousness (OR 3.47 95% CI [1.56; 7.70]). CONCLUSION Snakebite incidence and outcomes vary by region in Kenya, and treatment-seeking behaviors are complex. Work needs to be done to better characterize the spatial distribution of snakebite incidence in Kenya and efforts need to be made to ensure that victims have sufficient access to effective treatments to prevent death and serious injury.
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Affiliation(s)
- Peter S Larson
- Nagasaki University Institute of Tropical Medicine-Kenya Medical Research Institute (NUITM-KEMRI) Project, Kenya, Nagasaki, Nagasaki, Japan. .,Department of Epidemiology, University of Michigan School of Public Health, Ann Arbor, MI, USA. .,University of Michigan Institute for Social Research, Ann Arbor, MI, USA.
| | - Morris Ndemwa
- Nagasaki University Institute of Tropical Medicine-Kenya Medical Research Institute (NUITM-KEMRI) Project, Kenya, Nagasaki, Nagasaki, Japan
| | - Aleksandra F Thomas
- University of Michigan, Literature, Science and the Arts, Ann Arbor, MI, USA
| | - Noriko Tamari
- Nagasaki University Institute of Tropical Medicine-Kenya Medical Research Institute (NUITM-KEMRI) Project, Kenya, Nagasaki, Nagasaki, Japan
| | - Paul Diela
- Nagasaki University Institute of Tropical Medicine-Kenya Medical Research Institute (NUITM-KEMRI) Project, Kenya, Nagasaki, Nagasaki, Japan
| | - Mwatasa Changoma
- Nagasaki University Institute of Tropical Medicine-Kenya Medical Research Institute (NUITM-KEMRI) Project, Kenya, Nagasaki, Nagasaki, Japan.,Kenya Medical Research Institute, Nairobi, Kenya
| | | | | | - Kaan Cem Ketenci
- University of Michigan Institute for Social Research, Ann Arbor, MI, USA
| | - Kensuke Goto
- Division of Health and Safety Sciences Education, Osaka Kyoiku University, Osaka, Japan
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Snakebite Treatment in Tanzania: Identifying Gaps in Community Practices and Hospital Resources. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:ijerph19084701. [PMID: 35457571 PMCID: PMC9024466 DOI: 10.3390/ijerph19084701] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Revised: 04/09/2022] [Accepted: 04/11/2022] [Indexed: 01/18/2023]
Abstract
Snakebite envenoming causes more than 140,000 deaths annually and at least triple this number of disabilities. The World Health Organization classified snakebite as a Neglected Tropical Disease in 2017 and developed a strategy to halve death and disability from snakebite by 2030. To achieve this goal, snakebite victims need to receive safe and effective treatment. This descriptive, cross-sectional study surveyed student health professionals (N = 312) in Dar es Salaam, Tanzania, and was designed to identify major gaps in community practices and hospital resources for snakebite treatment. Participants reported using traditional community practices (44%, 95% confidence interval (CI) = 39–50%), allopathic practices (7%, 95% CI = 5–11%), or a combination of both (49%, 95% CI = 43–54%) to treat snakebite. Harmful practices included tight arterial tourniquets (46%, 95% CI = 41–52%) and wound incisions (15%, 95% CI = 11–19%). Many participants (35%, 95% CI = 29–40%) also turned to traditional healers. Students who treated snakebite injuries within the last 5 years (N = 69) also reported their general experiences with snakebite in hospitals. Hospitals often lacked essential resources to treat snakebite victims, and 44% (95% CI = 30–59%) of snakebite victims arrived at a hospital only three or more hours after the bite. A significant percentage of snakebite victims experienced lasting damage (32%, 95% CI = 20–47%) or death (14%, 95% CI = 7–25%). Snakebite outcomes could likely be improved if hospitals were universally and consistently equipped with the essential resources to treat snakebite victims, such as antivenoms. Educational interventions aimed at communities should focus on discouraging tourniquet use and tampering with the wound. Collaboration between the allopathic and traditional health system could further boost snakebite outcomes because traditional healers are often the first health workers to see snakebite victims.
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25
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Steegemans I, Sisay K, Nshimiyimana E, Gebrewold G, Piening T, Menberu Tessema E, Sahelie B, Alcoba G, Gebretsadik FS, Essink D, Collin S, Lucero E, Ritmeijer K. Treatment outcomes among snakebite patients in north-west Ethiopia-A retrospective analysis. PLoS Negl Trop Dis 2022; 16:e0010148. [PMID: 35139079 PMCID: PMC8863263 DOI: 10.1371/journal.pntd.0010148] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Revised: 02/22/2022] [Accepted: 01/05/2022] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Millions of people are bitten by venomous snakes annually, causing high mortality and disability, but the true burden of this neglected health issue remains unknown. Since 2015, Médecins Sans Frontières has been treating snakebite patients in a field hospital in north-west Ethiopia. Due to the poor market situation for effective and safe antivenoms for Sub-Saharan Africa, preferred antivenom was not always available, forcing changes in choice of antivenom used. This study describes treatment outcomes and the effectiveness and safety of different antivenoms used. METHODOLOGY / PRINCIPAL FINDINGS This retrospective observational study included 781 snakebite patients presenting at the field hospital between 2015 and 2019. Adjusted odds ratios, 95%-CI and p-values were used to compare the treatment outcome of patients treated with Fav-Afrique (n = 149), VacSera (n = 164), and EchiTAb-PLUS-ICP (n = 156) antivenom, and to identify the risk of adverse reactions for each antivenom. Whereas only incidental snakebite cases presented before 2015, after treatment was made available, cases rapidly increased to 1,431 in 2019. Envenomation was mainly attributed to North East African saw-scaled viper (Echis pyramidum) and puff adder (Bitis arietans). Patients treated with VacSera antivenom showed lower chance of uncomplicated treatment outcome (74.4%) compared to Fav-Afrique (93.2%) and EchiTAb-PLUS-ICP (90.4%). VacSera and EchiTAb-PLUS-ICP were associated with 16- and 6-fold adjusted odds of treatment reaction compared to Fav-Afrique, respectively, and VacSera was weakly associated with higher odds of death. CONCLUSIONS / SIGNIFICANCE Snakebite frequency is grossly underreported unless treatment options are available. Although EchiTAb-PLUS-ICP showed favorable outcomes in this retrospective analysis, prospective randomized trials are needed to evaluate the effectiveness and safety of the most promising antivenoms for Sub-Saharan Africa. Structural investment in sustained production and supply of antivenom is urgently needed.
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Affiliation(s)
- Inge Steegemans
- Médecins Sans Frontières, Amsterdam, The Netherlands
- VU University, Amsterdam, The Netherlands
| | | | | | | | | | | | | | | | | | | | - Simon Collin
- Federal University of Espírito Santo, Vitória, Brazil
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26
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Pelle RP, Engelbrecht A, Lalloo V. Case Report: Safe Tourniquet Removal in Black Mamba (Dendroaspis polylepis) Bites. Am J Trop Med Hyg 2022; 106:338-341. [PMID: 34724630 PMCID: PMC8733543 DOI: 10.4269/ajtmh.21-0374] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2021] [Accepted: 07/16/2021] [Indexed: 01/03/2023] Open
Abstract
The black mamba is known for its notorious potent neurotoxic venom. For this reason, their bites are often erroneously treated in the field with the application of a tourniquet in the hope of delaying systemic spread of the venom. Observational studies have shown that inappropriate tourniquet application is a common, harmful practice. An arterial tourniquet is not a recommended first aid measure because of the risk of limb ischemia and gangrene. When inappropriately applied, the rapid removal of the tourniquet in the emergency department may precipitate a life-threatening venom and metabolic toxin rush, leading to respiratory arrest. We present two cases of black mamba bites in Gauteng, South Africa, where gradual tourniquet removal was used to avoid a venom rush and rapid respiratory paralysis. Venom and metabolic toxin rush with potentially fatal respiratory muscle paralysis may be averted by gradual, cautious removal of field-applied tourniquets with concomitant antivenom administration.
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Affiliation(s)
- Ratang Pholosho Pelle
- Emergency Medicine, University of Pretoria, Pretoria, South Africa,Address correspondence to Ratang Pholosho Pelle, Emergency Department, Steve Biko Academic Hospital, Prinsoff, Gauteng, South Africa. E-mail:
| | | | - Vidya Lalloo
- Emergency Medicine, University of Pretoria, Pretoria, South Africa
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27
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Mender MM, Bolton F, Berry C, Young M. Antivenom: An immunotherapy for the treatment of snakebite envenoming in sub-Saharan Africa. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2021; 129:435-477. [PMID: 35305724 DOI: 10.1016/bs.apcsb.2021.11.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Snakebite envenoming (SBE) leads to significant morbidity and mortality, resulting in over 90,000 deaths and approximately 400,000 amputations annually. In sub-Saharan Africa (SSA) alone, SBE accounts for over 30,000 deaths per annum. Since 2017, SBE has been classified as a priority Neglected Tropical Disease (NTD) by the World Health Organisation (WHO). The major species responsible for mortality from SBE within SSA are from the Bitis, Dendroaspis, Echis and Naja genera. Pharmacologically active toxins such as metalloproteinases, serine proteinases, 3-finger toxins, kunitz-type toxins, and phospholipase A2s are the primary snake venom components. These toxins induce cytotoxicity, coagulopathy, hemorrhage, and neurotoxicity in envenomed victims. Antivenom is currently the only available venom-specific treatment for SBE and contains purified equine or ovine polyclonal antibodies, collected from donor animals repeatedly immunized with low doses of adjuvanted venom. The resulting plasma or serum contains a high titre of specific antibodies, which can then be collected and stored until required. The purified antibodies are either whole IgG, monovalent fragment antibody (Fab) or divalent fragment antibody F(ab')2. Despite pharmacokinetic and pharmacodynamic differences, all three are effective in the treatment of SBE. No antivenom is without adverse reactions but, the level of their impact and severity varies from benign early adverse reactions to the rarely occurring fatal anaphylactic shock. However, the major side effects are largely reversible with immediate administration of adrenaline and corticosteroids. There are 16 different antivenoms marketed within SSA, but the efficacy and safety profiles are only published for less than 50% of these products.
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Affiliation(s)
- Mender M Mender
- School of Bioscience, Cardiff University, Cardiff, United Kingdom; Department of Research and Development, MicroPharm Ltd, Newcastle Emlyn, United Kingdom.
| | - Fiona Bolton
- Department of Research and Development, MicroPharm Ltd, Newcastle Emlyn, United Kingdom
| | - Colin Berry
- School of Bioscience, Cardiff University, Cardiff, United Kingdom
| | - Mark Young
- School of Bioscience, Cardiff University, Cardiff, United Kingdom
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28
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Jenkins TP, Ahmadi S, Bittenbinder MA, Stewart TK, Akgun DE, Hale M, Nasrabadi NN, Wolff DS, Vonk FJ, Kool J, Laustsen AH. Terrestrial venomous animals, the envenomings they cause, and treatment perspectives in the Middle East and North Africa. PLoS Negl Trop Dis 2021; 15:e0009880. [PMID: 34855751 PMCID: PMC8638997 DOI: 10.1371/journal.pntd.0009880] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
The Middle East and Northern Africa, collectively known as the MENA region, are inhabited by a plethora of venomous animals that cause up to 420,000 bites and stings each year. To understand the resultant health burden and the key variables affecting it, this review describes the epidemiology of snake, scorpion, and spider envenomings primarily based on heterogenous hospital data in the MENA region and the pathologies associated with their venoms. In addition, we discuss the venom composition and the key medically relevant toxins of these venomous animals, and, finally, the antivenoms that are currently in use to counteract them. Unlike Asia and sub-Saharan Africa, scorpion stings are significantly more common (approximately 350,000 cases/year) than snakebites (approximately 70,000 cases/year) and present the most significant contributor to the overall health burden of envenomings, with spider bites being negligible. However, this review also indicates that there is a substantial lack of high-quality envenoming data available for the MENA region, rendering many of these estimates speculative. Our understanding of the venoms and the toxins they contain is also incomplete, but already presents clear trends. For instance, the majority of snake venoms contain snake venom metalloproteinases, while sodium channel-binding toxins and potassium channel-binding toxins are the scorpion toxins that cause most health-related challenges. There also currently exist a plethora of antivenoms, yet only few are clinically validated, and their high cost and limited availability present a substantial health challenge. Yet, some of the insights presented in this review might help direct future research and policy efforts toward the appropriate prioritization of efforts and aid the development of future therapeutic solutions, such as next-generation antivenoms.
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Affiliation(s)
- Timothy P Jenkins
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Shirin Ahmadi
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Matyas A Bittenbinder
- Naturalis Biodiversity Center, Leiden, the Netherlands
- Amsterdam Institute for Molecular and Life Sciences, Division of BioAnalytical Chemistry, Department of Chemistry and Pharmaceutical Sciences, Faculty of Sciences, Vrije Universiteit Amsterdam, Amsterdam, the Netherlands
- Centre for Analytical Sciences Amsterdam (CASA), Amsterdam, the Netherlands
| | - Trenton K Stewart
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Dilber E Akgun
- Department of Biomedical Engineering, Faculty of Engineering and Architecture, Eskişehir Osmangazi University, Eskişehir, Turkey
| | - Melissa Hale
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Nafiseh N Nasrabadi
- Pharmaceutical Sciences Research Centre, Student Research Commitee, School of Pharmacy, Shahid Beheshti University of Medical Sciences, Tehran, Iran
- Department of Venomous Animals and Antivenom Production, Razi Vaccine, and Serum Research Institute, Karaj, Iran
| | - Darian S Wolff
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Freek J Vonk
- Naturalis Biodiversity Center, Leiden, the Netherlands
- Amsterdam Institute for Molecular and Life Sciences, Division of BioAnalytical Chemistry, Department of Chemistry and Pharmaceutical Sciences, Faculty of Sciences, Vrije Universiteit Amsterdam, Amsterdam, the Netherlands
| | - Jeroen Kool
- Amsterdam Institute for Molecular and Life Sciences, Division of BioAnalytical Chemistry, Department of Chemistry and Pharmaceutical Sciences, Faculty of Sciences, Vrije Universiteit Amsterdam, Amsterdam, the Netherlands
- Centre for Analytical Sciences Amsterdam (CASA), Amsterdam, the Netherlands
| | - Andreas H Laustsen
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kongens Lyngby, Denmark
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29
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Potet J, Beran D, Ray N, Alcoba G, Habib AG, Iliyasu G, Waldmann B, Ralph R, Faiz MA, Monteiro WM, de Almeida Gonçalves Sachett J, di Fabio JL, Cortés MDLÁ, Brown NI, Williams DJ. Access to antivenoms in the developing world: A multidisciplinary analysis. Toxicon X 2021; 12:100086. [PMID: 34786555 PMCID: PMC8578041 DOI: 10.1016/j.toxcx.2021.100086] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Revised: 10/01/2021] [Accepted: 10/04/2021] [Indexed: 11/21/2022] Open
Abstract
Access to safe, effective, quality-assured antivenom products that are tailored to endemic venomous snake species is a crucial component of recent coordinated efforts to reduce the global burden of snakebite envenoming. Multiple access barriers may affect the journey of antivenoms from manufacturers to the bedsides of patients. Our review describes the antivenom ecosystem at different levels and identifies solutions to overcome these challenges. At the global level, there is insufficient manufacturing output to meet clinical needs, notably for antivenoms intended for use in regions with a scarcity of producers. At national level, variable funding and deficient regulation of certain antivenom markets can lead to the procurement of substandard antivenom. This is particularly true when producers fail to seek registration of their products in the countries where they should be used, or where weak assessment frameworks allow registration without local clinical evaluation. Out-of-pocket expenses by snakebite victims are often the main source of financing antivenoms, which results in the underuse or under-dosing of antivenoms, and a preference for low-cost products regardless of efficacy. In resource-constrained rural areas, where the majority of victims are bitten, supply of antivenom in peripheral health facilities is often unreliable. Misconceptions about treatment of snakebite envenoming are common, further reducing demand for antivenom and exacerbating delays in reaching facilities equipped for antivenom use. Multifaceted interventions are needed to improve antivenom access in resource-limited settings. Particular attention should be paid to the comprehensive list of actions proposed within the WHO Strategy for Prevention and Control of Snakebite Envenoming.
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Affiliation(s)
- Julien Potet
- Médecins Sans Frontières Access Campaign, Geneva, Switzerland
| | - David Beran
- Division of Tropical and Humanitarian Medicine, Geneva University Hospitals, Geneva, Switzerland
- Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Nicolas Ray
- GeoHealth Group, Institute of Global Health, Faculty of Medicine, University of Geneva, Geneva, Switzerland
- Institute for Environmental Sciences, University of Geneva, Geneva, Switzerland
| | - Gabriel Alcoba
- Division of Tropical and Humanitarian Medicine, Geneva University Hospitals, Geneva, Switzerland
- Médecins Sans Frontières, Medical Department, Operational Center Geneva, Geneva, Switzerland
| | - Abdulrazaq Garba Habib
- Infectious Disease and Tropical Medicine Unit, Department of Medicine, College of Health Science, Bayero University Kano, Nigeria
| | - Garba Iliyasu
- Infectious Disease and Tropical Medicine Unit, Department of Medicine, College of Health Science, Bayero University Kano, Nigeria
| | | | - Ravikar Ralph
- Department of Internal Medicine & Poisons Information Center, Christian Medical College, Vellore, 632004, Tamil Nadu, India
| | | | - Wuelton Marcelo Monteiro
- Department of Research, Fundação de Medicina Tropical Dr. Heitor Vieira Dourado, Manaus, Brazil
- School of Health Sciences, Universidade Do Estado Do Amazonas, Manaus, Brazil
| | | | | | | | - Nicholas I. Brown
- Global Snakebite Initiative, 19 Haig Street, Ashgrove, Qld, 4060, Australia
- University of Queensland, Australia
| | - David J. Williams
- Global Snakebite Initiative, 19 Haig Street, Ashgrove, Qld, 4060, Australia
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Chowdhury A, Lewin MR, Zdenek CN, Carter R, Fry BG. The Relative Efficacy of Chemically Diverse Small-Molecule Enzyme-Inhibitors Against Anticoagulant Activities of African Spitting Cobra ( Naja Species) Venoms. Front Immunol 2021; 12:752442. [PMID: 34691069 PMCID: PMC8529177 DOI: 10.3389/fimmu.2021.752442] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Accepted: 09/22/2021] [Indexed: 11/23/2022] Open
Abstract
African spitting cobras are unique among cobras for their potent anticoagulant venom activity arising from strong inhibition of Factor Xa. This anticoagulant effect is exerted by venom phospholipase A2 (Group I PLA2) toxins whose activity contributes to the lethality of these species. This anticoagulant toxicity is particularly problematic as it is not neutralized by current antivenoms. Previous work demonstrated this trait for Naja mossambica, N. nigricincta, N. nigricollis, and N. pallida. The present work builds upon previous research by testing across the full taxonomical range of African spitting cobras, demonstrating that N. ashei, N. katiensis, and N. nubiae are also potently anticoagulant through the inhibition of Factor Xa, and therefore the amplification of potent anticoagulant activity occurred at the base of the African spitting cobra radiation. Previous work demonstrated that the enzyme-inhibitor varespladib was able to neutralize this toxic action for N. mossambica, N. nigricincta, N. nigricollis, and N. pallida venoms. The current work demonstrates that varespladib was also able to neutralize N. ashei, N. katiensis, and N. nubiae. Thus varespladib is shown to have broad utility across the full range of African spitting cobras. In addition, we examined the cross-reactivity of the metalloprotease inhibitor prinomastat, which had been previously intriguingly indicated as being capable of neutralizing viperid venom PLA2 (Group II PLA2). In this study prinomastat inhibited the FXa-inhibiting PLA2 toxins of all the African spitting cobras at the same concentration at which it has been shown to inhibit metalloproteases, and thus was comparably effective in its cross-reactivity. In addition we showed that the metalloprotease-inhibitor marimastat was also able to cross-neutralize PLA2 but less effectively than prinomastat. Due to logistical (cold-chain requirement) and efficacy (cross-reactivity across snake species) limitations of traditional antivenoms, particularly in developing countries where snakebite is most common, these small molecule inhibitors (SMIs) might hold great promise as initial, field-based, treatments for snakebite envenoming as well as addressing fundamental limitations of antivenom in the clinical setting where certain toxin effects are unneutralized.
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Affiliation(s)
- Abhinandan Chowdhury
- Venom Evolution Lab, School of Biological Science, University of Queensland, St. Lucia, QLD, Australia.,Department of Biochemistry & Microbiology, North South University, Dhaka, Bangladesh
| | - Matthew R Lewin
- California Academy of Sciences, San Francisco, CA, United States.,Ophirex, Inc., Corte Madera, CA, United States
| | - Christina N Zdenek
- Venom Evolution Lab, School of Biological Science, University of Queensland, St. Lucia, QLD, Australia
| | | | - Bryan G Fry
- Venom Evolution Lab, School of Biological Science, University of Queensland, St. Lucia, QLD, Australia
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Yusuf AJ, Aleku GA, Bello UR, Liman DU. Prospects and Challenges of Developing Plant-Derived Snake Antivenin Natural Products: A Focus on West Africa. ChemMedChem 2021; 16:3635-3648. [PMID: 34585514 DOI: 10.1002/cmdc.202100478] [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: 07/06/2021] [Revised: 09/23/2021] [Indexed: 11/06/2022]
Abstract
Snakebite envenomation (SBE) is an important public health issue that is now receiving renewed attention following its reclassification as a Neglected Tropical Disease (NTD). Most incidences occur in rural areas of resource-limited countries, as such, timely and appropriate medical care for SBE is often inaccessible. The administration of anti-snake venom serum (ASV) is the only effective definitive treatment of SBE, but treatment failure to available ASVs is not uncommon. Emerging evidence highlights the potential of small-molecule compounds as inhibitors against toxins of snake venom. This presents an encouraging prospect to develop an alternative therapeutic option for the treatment SBE, that may be amenable for use at the point of care in resource-constraint settings. In view of the pivotal role of natural products in modern drug discovery programmes, there is considerable interest in ethno-pharmacological mining of medicinal plants and plant-derived medicinal compounds toward developing novel snake venom-neutralising therapeutics. In this review, we compile a collection of medicinal plants used in the treatment of SBE in West Africa and highlight their promise as potential botanical drugs or as sources of novel small-molecule compounds for the treatment of SBE. The challenges that must be surmounted to bring this to fruition including the need for (sub) regional collaboration have been discussed.
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Affiliation(s)
- Amina J Yusuf
- Department of Pharmaceutical & Medicinal Chemistry, Usmanu Danfodiyo University, Sokoto, Nigeria
| | - Godwin A Aleku
- Department of Biochemistry, University of Cambridge, Cambridge, CB2 1GA, UK
| | - Usman Rabiu Bello
- Biotechnology unit, Department of Life Sciences, Mewar University, Gangrar, Chittorgarh, Rajasthan, India
| | - Dahiru Umar Liman
- Department of Pharmaceutical & Medicinal Chemistry, Usmanu Danfodiyo University, Sokoto, Nigeria
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Menzies SK, Thomas AO, Tianyi FL, Abubakar SB, Nasidi A, Durfa N, Patel R, Trelfa A, Lalloo DG, Habib AG, Harrison RA. Livestock herding and Fulani ethnicity are a combined risk factor for development of early adverse reactions to antivenom treatment: Findings from a cross-sectional study in Nigeria. PLoS Negl Trop Dis 2021; 15:e0009518. [PMID: 34383742 PMCID: PMC8384187 DOI: 10.1371/journal.pntd.0009518] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2021] [Revised: 08/24/2021] [Accepted: 05/29/2021] [Indexed: 12/05/2022] Open
Abstract
Background Adverse reactions to antivenom considerably complicate the clinical management of snakebite envenomed patients because it necessitates a temporary suspension of life-saving antivenom, increases costs and can compromise patient outcomes. This study sought to explore the association between cattle-herding occupation and ethnic group and the occurrence of early adverse reactions to antivenom. Methods This cross-sectional study was conducted between the 25th April and 11th July 2011 at the Kaltungo General Hospital in north east Nigeria. The exposure variable of cattle-herding occupation showed a strong correlation with the ethnic group variable, thus these were combined into a new variable with three categories (Fulani and herder, either Fulani or herder, and neither Fulani nor herder). The outcome variable was the occurrence of early adverse reactions, defined as any new symptoms occurring within 6 hours of antivenom administration. Odds Ratios were estimated using multivariable logistic regression models controlling for potential confounders. Results Among 231 envenomed snakebite victims, the overall incidence of early adverse reactions was 11.9% (95% confidence intervals: 8.0–16.9%). Patients who were Fulani and herders had a higher incidence of early adverse reactions compared to patients who were neither Fulani nor herders (20% vs 5.7%). After adjusting for age and gender, victims who were Fulani and herders were 5.9 times more likely to have an early adverse reaction, compared to victims who were neither Fulani nor herders (95% CI: 1.88–18.59; p = 0.002). Interpretation To the best of our knowledge, this is the first study to provide evidence of higher odds of early adverse reactions among patients from a particular occupation and/or ethnic group. We recommend that snake envenomed patients of Fulani origin be especially closely monitored for adverse reactions, that hospitals receiving these patients be appropriately resourced to manage both envenoming and adverse reactions and that premedication with adrenaline should be considered. Our findings provide an argument for speculation on the influence of immunological or lifestyle-related differences on the occurrence of early adverse reactions to antivenom. Antivenom is the first-choice treatment of systemic snake envenoming that annually affects between 1.8–2.7 million victims globally. Access to antivenom is especially poor for those in greatest need because they typically reside in impoverished, rural tropical communities dependent upon health facilities with limited resources. In addition, clinical treatment of snakebite victims is further complicated by early adverse reactions (EARs) to antivenom-treatment. The causes of antivenom-associated EARs are poorly understood and under-researched. Despite antivenom producers instituting costly remedial manufacturing steps (removal of pyrogens and other impurities) to make their products safer, EARs still affect a high proportion of antivenom-treated patients. Instigated by anecdotal observations to the corresponding author from clinicians in rural Nigerian hospitals that snakebite victims of cattle-herding occupation, and especially those of Fulani ethnicity, suffer more frequent EARs than other groups, this cross-sectional study identified that risks of developing EARs to antivenom treatment include the ethnicity and pastoral lifestyle of snakebite patients. To our knowledge, this is the first study to identify that EARs to antivenom-treatment include factors associated with the victim, as well as factors related to the antivenom itself. We emphasise the need for more research on the causes of adverse reactions to antivenom so that strategies to reduce incidence can be implemented.
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Affiliation(s)
- Stefanie K Menzies
- Centre for Snakebite Research and Interventions, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, United Kingdom.,Centre for Drugs and Diagnostics, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Aniekan O Thomas
- Centre for Snakebite Research and Interventions, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Frank-Leonel Tianyi
- Centre for Snakebite Research and Interventions, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, United Kingdom.,Centre for Drugs and Diagnostics, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | | | | | - Nandul Durfa
- Special Projects Unit, Federal Ministry of Health, Abuja, Nigeria
| | - Rohit Patel
- Centre for Snakebite Research and Interventions, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, United Kingdom.,Centre for Drugs and Diagnostics, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Anna Trelfa
- Centre for Snakebite Research and Interventions, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - David G Lalloo
- Centre for Snakebite Research and Interventions, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, United Kingdom.,Centre for Drugs and Diagnostics, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | | | - Robert A Harrison
- Centre for Snakebite Research and Interventions, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, United Kingdom.,Centre for Drugs and Diagnostics, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
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Ooms GI, van Oirschot J, Okemo D, Waldmann B, Erulu E, Mantel-Teeuwisse AK, van den Ham HA, Reed T. Availability, affordability and stock-outs of commodities for the treatment of snakebite in Kenya. PLoS Negl Trop Dis 2021; 15:e0009702. [PMID: 34398889 PMCID: PMC8389522 DOI: 10.1371/journal.pntd.0009702] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Revised: 08/26/2021] [Accepted: 08/03/2021] [Indexed: 11/25/2022] Open
Abstract
BACKGROUND Annually, about 2.7 million snakebite envenomings occur globally. Alongside antivenom, patients usually require additional care to treat envenoming symptoms and antivenom side effects. Efforts are underway to improve snakebite care, but evidence from the ground to inform this is scarce. This study, therefore, investigated the availability, affordability, and stock-outs of antivenom and commodities for supportive snakebite care in health facilities across Kenya. METHODOLOGY/PRINCIPAL FINDINGS This study used an adaptation of the standardised World Health Organization (WHO)/Health Action International methodology. Data on commodity availability, prices and stock-outs were collected in July-August 2020 from public (n = 85), private (n = 36), and private not-for-profit (n = 12) facilities in Kenya. Stock-outs were measured retrospectively for a twelve-month period, enabling a comparison of a pre-COVID-19 period to stock-outs during COVID-19. Affordability was calculated using the wage of a lowest-paid government worker (LPGW) and the impoverishment approach. Accessibility was assessed combining the WHO availability target (≥80%) and LPGW affordability (<1 day's wage) measures. Overall availability of snakebite commodities was low (43.0%). Antivenom was available at 44.7% of public- and 19.4% of private facilities. Stock-outs of any snakebite commodity were common in the public- (18.6%) and private (11.7%) sectors, and had worsened during COVID-19 (10.6% versus 17.0% public sector, 8.4% versus 11.7% private sector). Affordability was not an issue in the public sector, while in the private sector the median cost of one vial of antivenom was 14.4 days' wage for an LPGW. Five commodities in the public sector and two in the private sector were deemed accessible. CONCLUSIONS Access to snakebite care is problematic in Kenya and seemed to have worsened during COVID-19. To improve access, efforts should focus on ensuring availability at both lower- and higher-level facilities, and improving the supply chain to reduce stock-outs. Including antivenom into Universal Health Coverage benefits packages would further facilitate accessibility.
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Affiliation(s)
- Gaby Isabelle Ooms
- Health Action International, Amsterdam, The Netherlands
- Utrecht Centre for Pharmaceutical Policy and Regulation, Division of Pharmacoepidemiology and Clinical Pharmacology, Utrecht Institute for Pharmaceutical Sciences (UIPS), Utrecht University, Utrecht, The Netherlands
| | | | | | | | | | - Aukje K Mantel-Teeuwisse
- Utrecht Centre for Pharmaceutical Policy and Regulation, Division of Pharmacoepidemiology and Clinical Pharmacology, Utrecht Institute for Pharmaceutical Sciences (UIPS), Utrecht University, Utrecht, The Netherlands
| | - Hendrika A van den Ham
- Utrecht Centre for Pharmaceutical Policy and Regulation, Division of Pharmacoepidemiology and Clinical Pharmacology, Utrecht Institute for Pharmaceutical Sciences (UIPS), Utrecht University, Utrecht, The Netherlands
| | - Tim Reed
- Health Action International, Amsterdam, The Netherlands
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Abouyannis M, Aggarwal D, Lalloo DG, Casewell NR, Hamaluba M, Esmail H. Clinical outcomes and outcome measurement tools reported in randomised controlled trials of treatment for snakebite envenoming: A systematic review. PLoS Negl Trop Dis 2021; 15:e0009589. [PMID: 34339410 PMCID: PMC8360524 DOI: 10.1371/journal.pntd.0009589] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Revised: 08/12/2021] [Accepted: 06/24/2021] [Indexed: 02/02/2023] Open
Abstract
BACKGROUND Snakebite is a priority neglected tropical disease and causes a range of complications that vary depending on the snake species. Randomised clinical trials have used varied outcome measures that do not allow results to be compared or combined. In accordance with the Core Outcomes Measurements in Effectiveness Trials (COMET) initiative, this systematic review aims to support the development of a globally relevant core outcome set for snakebite. METHODS All randomised controlled trials, secondary analyses of randomised controlled trials and study protocols investigating the efficacy of therapeutics for human snakebite envenoming were eligible for inclusion. Study screening and data extraction were conducted in duplicate by two independent reviewers. All primary and secondary outcome measures were extracted and compiled, as were adverse event outcome measures. Similar outcome measures were grouped into domains. The study was prospectively registered with PROSPERO: CRD42020196160. RESULTS This systematic review included 43 randomised controlled trials, two secondary analyses and 13 study protocols. A total of 382 outcome measures were extracted and, after duplicates were merged, there were 153 unique outcomes. The most frequently used outcome domain ('venom antigenaemia') was included in less than one third of the studies. The unique outcomes were classified into 60 outcome domains. Patient-centred outcomes were used in only three of the studies. DISCUSSION Significant heterogeneity in outcome measures exists in snakebite clinical trials. Consensus is needed to select outcome measures that are valid, reliable, patient-centred and feasible. The results of this systematic review strongly support the development of a core outcome set for use in snakebite clinical trials.
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Affiliation(s)
- Michael Abouyannis
- Centre for Snakebite Research and Interventions, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
- KEMRI-Wellcome Research Programme, Kilifi, Kenya
| | - Dinesh Aggarwal
- Department of Medicine, University of Cambridge, Cambridge, United Kingdom
| | - David G. Lalloo
- Centre for Snakebite Research and Interventions, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Nicholas R. Casewell
- Centre for Snakebite Research and Interventions, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Mainga Hamaluba
- KEMRI-Wellcome Research Programme, Kilifi, Kenya
- Centre for Tropical Medicine & Global Health, Nuffield Department of Medicine, Oxford, United Kingdom
| | - Hanif Esmail
- MRC clinical trials unit at UCL, London, United Kingdom
- Institute for Global Health, University College London, London, United Kingdom
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Duda R, Monteiro WM, Giles-Vernick T. Integrating lay knowledge and practice into snakebite prevention and care in central Africa, a hotspot for envenomation. Toxicon X 2021; 11:100077. [PMID: 34381993 PMCID: PMC8334740 DOI: 10.1016/j.toxcx.2021.100077] [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: 04/20/2021] [Revised: 07/12/2021] [Accepted: 07/14/2021] [Indexed: 11/23/2022] Open
Abstract
The WHO has identified the goal of halving deaths and disability from snakebite envenomation (SBE) by 2030 through a four-pillar program that promotes accessible and affordable treatments, strengthens health systems, promotes community and multi-level engagement, and mobilizes partnerships, coordination and resources to advocate for global action. This initiative could accelerate multi-disciplinary research and action in central Africa, a “hotspot” for SBE, but it offers little specific guidance about anthropological research to be conducted. This commentary develops that research agenda. It surveys anthropological, ethnohistorical investigations in the central African forest to elaborate the socio-cultural and historical significance and practices around snakes and snakebites. It draws from south and southeast Asian and Latin American literatures to illustrate anthropological contributions to SBE research. It then outlines a Central African research agenda employing ethnobiological investigation of snake ecologies, participatory evaluations of humans-snake contacts, and interviews and participant-observation of local prevention and treatment practices and knowledge. This research will co-develop policies and practices with forest communities and leaders and regional and national authorities to reduce the burden of SBE. Central African forests are a hotspot for snakebite envenomation. SBE research in central Africa has not mobilized anthropological literatures or methodologies. Policies to reduce SBE burden in central Africa should build on participatory research. Policies to reduce SBE burden should be co-developed with local and national stakeholders.
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Affiliation(s)
- Romain Duda
- Anthropology & Ecology of Disease Emergence Unit, Institut Pasteur, Paris, France
| | - Wuelton M Monteiro
- School of Health Sciences, Universidade Do Estado Do Amazonas, Manaus, Brazil.,Department of Research, Fundação de Medicina Tropical Dr. Heitor Vieira Dourado, Manaus, Brazil
| | - Tamara Giles-Vernick
- Anthropology & Ecology of Disease Emergence Unit, Institut Pasteur, Paris, France
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Kasturiratne A, Lalloo DG, Janaka de Silva H. Chronic health effects and cost of snakebite. Toxicon X 2021; 9-10:100074. [PMID: 34355162 PMCID: PMC8321925 DOI: 10.1016/j.toxcx.2021.100074] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Revised: 06/29/2021] [Accepted: 07/07/2021] [Indexed: 11/29/2022] Open
Abstract
The burden of disability among survivors and the socio-economic impact of snakebite have not been adequately researched. We reviewed original research articles, case reports and small case series relating to chronic physical, mental and psycho-social disability and economic burden of snakebite. Both physical and psychological health problems seem common in snakebite survivors and can lead to disability and loss of productivity. Chronic physical health effects, musculoskeletal disability being the commonest, can be largely attributed to limited and delayed access to optimal treatment of acute envenoming. The economic burden is considerable, and includes health system costs, out-of-pocket expenditure and opportunity costs, with regional variations. Health systems should be more responsive to needs and circumstances of bite victims, and a more holistic approach should be developed in the treatment of snakebite which incorporates the management of chronic health effects. Limited attention has been paid to chronic disability and the socio-economic impact of snakebite. Physical and psychological health problems occur in snakebite survivors leading to disability and loss of productivity. Chronic health effects can be largely attributed to limited and delayed access to optimal treatment of acute envenoming. Economic burden includes health system costs, out-of-pocket expenditure and opportunity costs. Health systems should be responsive to needs and circumstances of bite victims including care of chronic health effects.
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Ahmed S, Koudou GB, Bagot M, Drabo F, Bougma WR, Pulford C, Bockarie M, Harrison RA. Health and economic burden estimates of snakebite management upon health facilities in three regions of southern Burkina Faso. PLoS Negl Trop Dis 2021; 15:e0009464. [PMID: 34153048 PMCID: PMC8248599 DOI: 10.1371/journal.pntd.0009464] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Revised: 07/01/2021] [Accepted: 05/11/2021] [Indexed: 11/29/2022] Open
Abstract
Background Snakebite has become better recognized as a significant cause of death and disability in Sub-Saharan Africa, but the health economic consequences to victims and health infrastructures serving them remain poorly understood. This information gap is important as it provides an evidence-base guiding national and international health policy decision making on the most cost-effective interventions to better manage snakebite. Here, we assessed hospital-based data to estimate the health economic burden of snakebite in three regions of Burkina Faso (Centre-Ouest, Hauts Bassins and Sud-Ouest). Methodology Primary data of snakebite victims admitted to regional and district health facilities (eg, number of admissions, mortality, hospital bed days occupied) was collected in three regions over 17 months in 2013/14. The health burden of snakebite was assessed using Disability-Adjusted Life Years (DALYs) calculations based upon hospitalisation, mortality and disability data from admitted patients amongst other inputs from secondary sources (eg, populations, life-expectancy and age-weighting constants). An activity-based costing approach to determine the direct cost of snake envenoming included unit costs of clinical staff wages, antivenom, supportive care and equipment extracted from context-relevant literature. Findings The 10,165 snakebite victims admitted to hospital occupied 28,164 hospital bed days over 17 months. The annual rate of hospitalisation and mortality of admitted snakebite victims was 173 and 1.39/100,000 population, respectively. The estimated annual (i) DALYs lost was 2,153 (0.52/1,000) and (ii) cost to hospitals was USD 506,413 (USD 49/hospitalisation) in these three regions of Burkina Faso. These costs appeared to be influenced by the number of patients receiving antivenom (10.90% in total) in each area (highest in Sud-Ouest) and the type of health facility. Conclusion The economic burden of snake envenoming is primarily shouldered by the rural health centres closest to snakebite victims–facilities that are typically least well equipped or resourced to manage this burden. Our study highlights the need for more research in other regions/countries to demonstrate the burden of snakebite and the socioeconomic benefits of its management. This evidence can guide the most cost-effective intervention from government and development partners to meet the snakebite-management needs of rural communities and their health centres. The World Health Organisation has established a strategy to halve snakebite mortality and morbidity by 2030. Achieving this ambitious target within a decade will require substantial investment from governments of countries most affected by snakebite. The burden of snakebite however, is typically greatest in low-middle income countries with already limited health budgets. Acquiring government support to prioritise snakebite over other prevailing diseases will require evidence of the scale, causes, precise geographies and health economic impacts of snakebite. While the snakebite research community has progressed the delivery of some of these evidence types, it has been weak at providing evidence of the health economic burden of snakebite. Our hospital-based study identifies the health (Disability-Adjusted Life Years) and financial burdens of snakebite to three districts of Burkina Faso. We argue that funding of more health economic research, performed at greater depth and that includes cost-effectiveness of snakebite treatment and other remedial interventions is arguably the most effective tool to advocate for the policy support and investment required of national and international health agencies to deliver WHO’s laudable 2030 target for snakebite.
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Affiliation(s)
- Sayem Ahmed
- The Centre for Snakebite Research & Interventions, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
- The Centre for Neglected Tropical Diseases, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
- Mathematical Modelling Group, Oxford University Clinical Research Unit (OUCRU), Ho Chi Minh City, Vietnam
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, United Kingdom
| | - Guibehi B. Koudou
- The Centre for Neglected Tropical Diseases, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
- Centre Suisse de Recherches Scientifiques, Abidjan, Cote d’Ivoire
| | - Maïwenn Bagot
- The Centre for Snakebite Research & Interventions, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - François Drabo
- Ministère de la Santé, Direction de la Promotion de la Santé, Ouagadougou, Burkina Faso
| | - Windtaré R. Bougma
- Ministère de la Santé, Direction de la Prévention de la Santé de la Population, Programme National de lute contre les Maladies Tropicales Négligées, Ouagadougou, Burkina Faso
| | - Caisey Pulford
- The Centre for Snakebite Research & Interventions, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
- National Infection Service, Public Health England Colindale, London, United Kingdom
- Institute of infection, Veterinary and Ecological Sciences, University of Liverpool, Liverpool, United Kingdom
| | - Moses Bockarie
- The Centre for Neglected Tropical Diseases, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
- School of Community Health Sciences, Njala University, Bo Campus, Bo, Sierra Leone
| | - Robert A. Harrison
- The Centre for Snakebite Research & Interventions, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
- The Centre for Neglected Tropical Diseases, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
- * E-mail:
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Clare RH, Hall SR, Patel RN, Casewell NR. Small Molecule Drug Discovery for Neglected Tropical Snakebite. Trends Pharmacol Sci 2021; 42:340-353. [DOI: 10.1016/j.tips.2021.02.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2020] [Revised: 02/24/2021] [Accepted: 02/26/2021] [Indexed: 12/31/2022]
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'The medicine is not for sale': Practices of traditional healers in snakebite envenoming in Ghana. PLoS Negl Trop Dis 2021; 15:e0009298. [PMID: 33861735 PMCID: PMC8081335 DOI: 10.1371/journal.pntd.0009298] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2020] [Revised: 04/28/2021] [Accepted: 03/07/2021] [Indexed: 11/19/2022] Open
Abstract
Background Snakebite envenoming is a medical emergency which is common in many tropical lower- and middle-income countries. Traditional healers are frequently consulted as primary care-givers for snakebite victims in distress. Traditional healers therefore present a valuable source of information about how snakebite is perceived and handled at the community level, an understanding of which is critical to improve and extend snakebite-related healthcare. Method The study was approached from the interpretive paradigm with phenomenology as a methodology. Semi-structured interviews were conducted with 19 traditional healers who treat snakebite patients in two rural settings in Ghana. From the Ashanti and Upper West regions respectively, 11 and 8 healers were purposively sampled. Interview data was coded, collated and analysed thematically using ATLAS.ti 8 software. Demographic statistics were analysed using IBM SPSS Statistics version 26. Findings Snakebite was reportedly a frequent occurrence, perceived as dangerous and often deadly by healers. Healers felt optimistic in establishing a diagnosis of snakebite using a multitude of methods, ranging from herbal applications to spiritual consultations. They were equally confident about their therapies; encompassing the administration of plant and animal-based concoctions and manipulations of bite wounds. Traditional healers were consulted for both physical and spiritual manifestations of snakebite or after insufficient pain control and lack of antivenom at hospitals; referrals by healers to hospitals were primarily done to receive antivenom and care for wound complications. Most healers welcomed opportunities to engage more productively with hospitals and clinical staff. Conclusions The fact that traditional healers did sometimes refer victims to hospitals indicates that improvement of antivenom stocks, pain management and wound care can potentially improve health seeking at hospitals. Our results emphasize the need to explore future avenues for communication and collaboration with traditional healers to improve health seeking behaviour and the delivery of much-needed healthcare to snakebite victims. Many snakebites in tropical lower and middle-income countries are treated at the community level by traditional healers whose services are often accessible, affordable and offer care within the realms of local tradition and culture. A drawback of traditional care, however, is the associated delay or non-presentation of patients in need of antivenom and medical management at hospitals. We conducted interviews with traditional healers in two separate areas of rural Ghana to chart the socio-cultural context, perceived problems, treatment approaches, health seeking behaviors, and possibilities for future collaboration in snakebite treatment and management between hospitals and traditional healers. Healers described a holistic treatment approach, addressing physiological, psychological, and spiritual complications of snakebite. Healers reported high success rates with therapies ranging from herbal medicine to minor surgical interventions. Major factors precluding hospital health seeking of patients were identified as costs, poor accessibility, lack of antivenom and insufficient pain control. Gaps in clinical management are modifiable factors that, if improved, are likely to increase clinical health seeking. Our findings emphasize that traditional healers can provide a critical link between snakebite patients and hospitals, making their involvement crucial to the rural expansion of snakebite research and emergency care.
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Tan CH, Liew JL, Chong HP, Tan NH. Protein decomplexation and proteomics: A complementary assessment method of the physicochemical purity of antivenom. Biologicals 2021; 69:22-29. [PMID: 33431232 DOI: 10.1016/j.biologicals.2020.12.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2020] [Revised: 11/28/2020] [Accepted: 12/22/2020] [Indexed: 01/21/2023] Open
Abstract
The quality of antivenom is governed by its safety and efficacy profiles. These quality characteristics are much influenced by the purity of antivenom content. Rigorous assessment and meticulous monitoring of antivenom purity at the preclinical setting is hence crucial. This study aimed to explore an integrative proteomic method to assess the physicochemical purity of four commercially available antivenoms in the region. The antivenoms were subjected to Superdex 200 HR 10/30 size-exclusion fast-protein liquid chromatography (SE-FPLC). The proteins in each fraction were trypsin-digested and analyzed by nano-ESI-liquid chromatography-tandem mass spectrometry (LC-MS/MS). SE-FPLC resolved the antivenom proteins into three major protein components of very high (>200 kDa), high (100-120 kDa) and medium (<60 kDa) molecular weights. The major components (80-95% of total proteins) in the antivenoms were proteins of 100-120 kDa consisting of mainly the light and partially digested heavy immunoglobulin chains, consistent with F(ab')2 as the active principle of the antivenoms. However, LC-MS/MS also detected substantial quantity of large proteins (e.g. alpha-2-macroglobulins), immunoglobulin aggregates and impurities e.g. albumins in some products. The method is practical and able to unveil the quantitative and qualitative aspects of antivenom protein compositions. It is therefore a potentially useful preclinical assessment tool of antivenom purity.
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Affiliation(s)
- Choo Hock Tan
- Venom Research and Toxicology Laboratory, Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia.
| | - Jia Lee Liew
- Venom Research and Toxicology Laboratory, Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Ho Phin Chong
- Venom Research and Toxicology Laboratory, Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Nget Hong Tan
- Department of Molecular Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
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Ooms GI, van Oirschot J, Waldmann B, von Bernus S, van den Ham HA, Mantel-Teeuwisse AK, Reed T. The Current State of Snakebite Care in Kenya, Uganda, and Zambia: Healthcare Workers' Perspectives and Knowledge, and Health Facilities' Treatment Capacity. Am J Trop Med Hyg 2020; 104:774-782. [PMID: 33236717 DOI: 10.4269/ajtmh.20-1078] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Accepted: 10/08/2020] [Indexed: 11/07/2022] Open
Abstract
Snakebites continue to be a public health concern in sub-Saharan Africa, where availability of appropriate medical treatment is rare, even though death and disability can be prevented with timely intervention. A challenge is the lack of sociopolitical studies to inform health policies. This study aimed to identify snakebite patient profiles, healthcare workers' (HCWs) knowledge of snakebite, and facilities' snakebite treatment capacity in Kenya, Uganda, and Zambia to inform interventions to improve access to appropriate treatment. The research comprised a cross-sectional key informant survey among HCWs from health facilities in Kenya (n = 145), Uganda (n = 144), and Zambia (n = 108). Data were collected between March 2018 and November 2019. Most of the HCWs suggested that the number of snakebite incidents was similar between the genders, that most patients were aged 21-30 years, and most people were bitten when farming or walking. Overall, only 12% of HCWs had received formal training in snakebite management. Only about 20% of HCWs in each country said their health facility had the medicines needed to treat snakebites, with antivenom available in 0-34% of facilities across the sectors and countries, and snakebites were not systematically recorded. This research shows that an integrative approach through policies to increase resource allocation for health system strengthening, including community education, HCW training, and improved access to snakebite treatment, is needed. Part of this approach should include regulations that ensure antivenoms available in health facilities meet quality control standards and that snakebites are accommodated into routine reporting systems to assess progress.
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Affiliation(s)
- Gaby I Ooms
- Health Action International, Amsterdam, The Netherlands.,Division of Pharmacoepidemiology and Clinical Pharmacology, Utrecht Centre for Pharmaceutical Policy and Regulation, Utrecht Institute for Pharmaceutical Sciences (UIPS), Utrecht University, Utrecht, The Netherlands
| | | | | | | | - Hendrika A van den Ham
- Division of Pharmacoepidemiology and Clinical Pharmacology, Utrecht Centre for Pharmaceutical Policy and Regulation, Utrecht Institute for Pharmaceutical Sciences (UIPS), Utrecht University, Utrecht, The Netherlands
| | - Aukje K Mantel-Teeuwisse
- Division of Pharmacoepidemiology and Clinical Pharmacology, Utrecht Centre for Pharmaceutical Policy and Regulation, Utrecht Institute for Pharmaceutical Sciences (UIPS), Utrecht University, Utrecht, The Netherlands
| | - Tim Reed
- Health Action International, Amsterdam, The Netherlands
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Bhaumik S, Beri D, Lassi ZS, Jagnoor J. Interventions for the management of snakebite envenoming: An overview of systematic reviews. PLoS Negl Trop Dis 2020; 14:e0008727. [PMID: 33048936 PMCID: PMC7584233 DOI: 10.1371/journal.pntd.0008727] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Revised: 10/23/2020] [Accepted: 08/17/2020] [Indexed: 01/08/2023] Open
Abstract
INTRODUCTION Snakebite is a neglected tropical disease that leads to more than 120,000 deaths every year. In 2019, World Health Organization (WHO) launched a strategy to decrease its global burden by 2030. There is a range of issues around different interventions for the management of snakebite. Decisions around these interventions should be informed by evidence from systematic reviews (SR). METHODS An overview of SRs was conducted by searching 12 electronic databases, PROSPERO, contacting experts and screening the bibliography of included reviews. Screening, data extraction, and quality assessment (through AMSTAR-2) was done by at least two overview authors independently with discrepancies sorted by consensus. A narrative synthesis was conducted. PRINCIPLE FINDINGS The overview found 13 completed SRs that has looked at various aspects of management of snakebite envenomation. There was one SR on first aid, nine on effectiveness and safety of snake anti-venom (SAV), two on drugs to prevent adverse reactions due to SAV therapy, and one on surgical interventions for management of snakebite envenomation. All, except one, SR was appraised to have critically low confidence as per AMSTAR-2 Criteria. Evidence base was restricted to few studies for most interventions. DISCUSSION High quality evidence from SRs is required to inform guidelines and health system decisions which can bring down the burden of snakebite. The review indicates the need to fund high-quality SRs, evidence gaps and core outcome sets which can inform guideline recommendations, funding priorities for conduct of future trials. Variation in species distribution as well as intra-species variation in venom composition implies the need for conduct of region or, nation or state (sub-national) specific randomised controlled trials and SRs on different SAVs and their dosing regimens.
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Affiliation(s)
- Soumyadeep Bhaumik
- The George Institute for Global Health, University of New South Wales, Sydney, New South Wales, Australia
- The George Institute for Global Health, New Delhi, India
- * E-mail:
| | - Deepti Beri
- The George Institute for Global Health, New Delhi, India
| | - Zohra S. Lassi
- Robinson Research Institute, The University of Adelaide, North Terrace, Adelaide, South Australia, Australia
| | - Jagnoor Jagnoor
- The George Institute for Global Health, University of New South Wales, Sydney, New South Wales, Australia
- The George Institute for Global Health, New Delhi, India
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Zurbano BN, Tavarone E, Viacava BG, Dokmetjian JC, Cascone O, Fingermann M. Critical aspects on traditional antivenom production processes and their optimization by factorial analysis. Biologicals 2020; 68:65-73. [PMID: 32912811 DOI: 10.1016/j.biologicals.2020.08.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2020] [Revised: 08/02/2020] [Accepted: 08/11/2020] [Indexed: 10/23/2022] Open
Abstract
Most antivenoms are produced by techniques developed over 50 years ago, with minor modifications. Herein we revise the core of traditional antivenom production processes aiming to optimize key determinants for both consistent antivenom production and the best balance between F(ab')2 quality and recovery. Factorial design analysis revealed that pepsin digestion of 1:3 saline diluted equine plasma for 60 min under pH: 3.20, 37 °C temperature and a 1:15 pepsin to protein ratio conditions, allowed to achieve maximal IgG to F(ab')2 conversion with minimal protein aggregate formation. Further downstream processing by salting out with ammonium sulfate was also studied by factorial analysis. The influence of ammonium sulfate (AS) concentration, temperature (T) and the albumin to total plasma protein ratio plasma (Alb:P) were assayed, revealing that both AS, T and their interaction have a significant impact in F(ab')2 quality and recovery. Taking into account the existing compromise between F(ab')2 monomer recovery and quality two alternative conditions were selected: 14 g/dl AS at 56 °C and, alternatively 16 g/dl AS at 30 °C. Reasonable yields (42%) and product quality (2.5% of aggregates) without significant changes in production cost of traditional methodologies was achieved under the optimized conditions found.
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Affiliation(s)
- Beatriz N Zurbano
- Instituto Nacional de Producción de Biológicos (INPB), ANLIS "Dr. Carlos G. Malbrán", Vélez Sársfield 563, 1282, Buenos Aires, Argentina
| | - Eugenia Tavarone
- Instituto Nacional de Producción de Biológicos (INPB), ANLIS "Dr. Carlos G. Malbrán", Vélez Sársfield 563, 1282, Buenos Aires, Argentina
| | - Belén González Viacava
- Instituto Nacional de Producción de Biológicos (INPB), ANLIS "Dr. Carlos G. Malbrán", Vélez Sársfield 563, 1282, Buenos Aires, Argentina
| | - José C Dokmetjian
- Instituto Nacional de Producción de Biológicos (INPB), ANLIS "Dr. Carlos G. Malbrán", Vélez Sársfield 563, 1282, Buenos Aires, Argentina
| | - Osvaldo Cascone
- Instituto Nacional de Producción de Biológicos (INPB), ANLIS "Dr. Carlos G. Malbrán", Vélez Sársfield 563, 1282, Buenos Aires, Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Godoy Cruz 2290, 1425, Buenos Aires, Argentina; Instituto de Nanobiotecnología (NANOBIOTEC), CONICET-Universidad de Buenos Aires, Junín 956, 1113, Buenos Aires, Argentina; Cátedra de Biotecnología, Departamento de Microbiología, Inmunología, Biotecnología y Genética, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Junín 956, 1113, Buenos Aires, Argentina
| | - Matías Fingermann
- Instituto Nacional de Producción de Biológicos (INPB), ANLIS "Dr. Carlos G. Malbrán", Vélez Sársfield 563, 1282, Buenos Aires, Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Godoy Cruz 2290, 1425, Buenos Aires, Argentina.
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Harrison RA, Williams DJ. Outlining progress since the first International Snakebite Awareness Day and some key challenges for next year. Trans R Soc Trop Med Hyg 2020; 113:577-578. [PMID: 31539057 DOI: 10.1093/trstmh/trz096] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2019] [Accepted: 08/08/2019] [Indexed: 11/13/2022] Open
Affiliation(s)
- Robert A Harrison
- Centre for Snakebite Research & Interventions, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, UK
| | - David J Williams
- Australia Venom Research Unit, University of Melbourne, Australia
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Habib AG, Musa BM, Iliyasu G, Hamza M, Kuznik A, Chippaux JP. Challenges and prospects of snake antivenom supply in sub-Saharan Africa. PLoS Negl Trop Dis 2020; 14:e0008374. [PMID: 32817674 PMCID: PMC7440614 DOI: 10.1371/journal.pntd.0008374] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Affiliation(s)
- Abdulrazaq G. Habib
- Health Economics & Outcomes Research (H-CORE) Group, Department of Medicine, Bayero University, Kano, Nigeria
- Venom and Antivenom Research Project (VASP), Bayero University, Kano, Nigeria
- African Snakebite Research Group (ASRG) Project, Bayero University, Kano, Nigeria
- Africa Center of Excellence in Population Health and Policy, Bayero University, Kano, Nigeria
- * E-mail:
| | - Baba M. Musa
- Health Economics & Outcomes Research (H-CORE) Group, Department of Medicine, Bayero University, Kano, Nigeria
- Africa Center of Excellence in Population Health and Policy, Bayero University, Kano, Nigeria
| | - Garba Iliyasu
- Health Economics & Outcomes Research (H-CORE) Group, Department of Medicine, Bayero University, Kano, Nigeria
- Venom and Antivenom Research Project (VASP), Bayero University, Kano, Nigeria
- African Snakebite Research Group (ASRG) Project, Bayero University, Kano, Nigeria
- Africa Center of Excellence in Population Health and Policy, Bayero University, Kano, Nigeria
| | - Muhammad Hamza
- Venom and Antivenom Research Project (VASP), Bayero University, Kano, Nigeria
- African Snakebite Research Group (ASRG) Project, Bayero University, Kano, Nigeria
| | - Andreas Kuznik
- Regeneron Pharmaceuticals, Tarrytown, New York, United States of America
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Ainsworth S, Menzies SK, Casewell NR, Harrison RA. An analysis of preclinical efficacy testing of antivenoms for sub-Saharan Africa: Inadequate independent scrutiny and poor-quality reporting are barriers to improving snakebite treatment and management. PLoS Negl Trop Dis 2020; 14:e0008579. [PMID: 32817682 PMCID: PMC7462309 DOI: 10.1371/journal.pntd.0008579] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Revised: 09/01/2020] [Accepted: 07/08/2020] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND The World Health Organization's strategy to halve snakebite mortality and morbidity by 2030 includes an emphasis on a risk-benefit process assessing the preclinical efficacy of antivenoms manufactured for sub-Saharan Africa. To assist this process, we systematically collected, standardised and analysed all publicly available data on the preclinical efficacy of antivenoms designed for sub-Saharan Africa. METHODOLOGY/PRINCIPAL FINDINGS Using a systematic search of publication databases, we focused on publicly available preclinical reports of the efficacy of 16 antivenom products available in sub Saharan Africa. Publications since 1999 reporting the industry standard intravenous pre-incubation method of murine in vivo neutralisation of venom lethality (median effective dose [ED50]) were included. Eighteen publications met the criteria. To permit comparison of the several different reported ED50 values, it was necessary to standardise these to microlitre of antivenom resulting in 50% survival of mice challenged per milligram of venom (μl/mg). We were unable to identify publicly available preclinical data on four antivenoms, whilst data for six polyspecific antivenoms were restricted to a small number of venoms. Only four antivenoms were tested against a wide range of venoms. Examination of these studies for the reporting of key metrics required for interpreting antivenom ED50s were highly variable, as evidenced by eight different units being used for the described ED50 values. CONCLUSIONS/SIGNIFICANCE There is a disturbing lack of (i) preclinical efficacy testing of antivenom for sub Saharan Africa, (ii) publicly available reports and (iii) independent scrutiny of this medically important data. Where reports do exist, the methods and metrics used are highly variable. This prevents comprehensive meta-analysis of antivenom preclinical efficacy, and severely reduces the utility of antivenom ED50 results in the decision making of physicians treating patients and of national and international health agencies. Here, we propose the use of a standardised result reporting checklist to resolve this issue. Implementation of these straightforward steps will deliver uniform evaluation of products across laboratories, facilitate meta-analyses, and contribute vital information for designing the clinical trials needed to achieve the WHO target of halving snakebite morbidity and mortality by 2030.
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Affiliation(s)
- Stuart Ainsworth
- Centre for Snakebite Research and Interventions, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, United Kingdom
| | - Stefanie K. Menzies
- Centre for Snakebite Research and Interventions, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, United Kingdom
| | - Nicholas R. Casewell
- Centre for Snakebite Research and Interventions, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, United Kingdom
| | - Robert A. Harrison
- Centre for Snakebite Research and Interventions, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, United Kingdom
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Casewell NR, Jackson TNW, Laustsen AH, Sunagar K. Causes and Consequences of Snake Venom Variation. Trends Pharmacol Sci 2020; 41:570-581. [PMID: 32564899 PMCID: PMC7116101 DOI: 10.1016/j.tips.2020.05.006] [Citation(s) in RCA: 167] [Impact Index Per Article: 41.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Revised: 05/25/2020] [Accepted: 05/31/2020] [Indexed: 11/30/2022]
Abstract
Snake venoms are mixtures of toxins that vary extensively between and within snake species. This variability has serious consequences for the management of the world’s 1.8 million annual snakebite victims. Advances in ‘omic’ technologies have empowered toxinologists to comprehensively characterize snake venom compositions, unravel the molecular mechanisms that underpin venom variation, and elucidate the ensuing functional consequences. In this review, we describe how such mechanistic processes have resulted in suites of toxin isoforms that cause diverse pathologies in human snakebite victims and we detail how variation in venom composition can result in treatment failure. Finally, we outline current therapeutic approaches designed to circumvent venom variation and deliver next-generation treatments for the world’s most lethal neglected tropical disease.
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Affiliation(s)
- Nicholas R Casewell
- Centre for Snakebite Research and Interventions, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK.
| | - Timothy N W Jackson
- Australian Venom Research Unit, Department of Pharmacology and Therapeutics, University of Melbourne, Victoria, Australia
| | - Andreas H Laustsen
- Department of Biotechnology and Biomedicine, Technical University of Denmark, DK-2800 Kongens Lyngby, Denmark
| | - Kartik Sunagar
- Evolutionary Venomics Laboratory, Centre for Ecological Sciences, Indian Institute of Science, Bangalore 560012, Karnataka, India
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Diagnostic and Therapeutic Value of Aptamers in Envenomation Cases. Int J Mol Sci 2020; 21:ijms21103565. [PMID: 32443562 PMCID: PMC7278915 DOI: 10.3390/ijms21103565] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2020] [Revised: 05/11/2020] [Accepted: 05/13/2020] [Indexed: 02/07/2023] Open
Abstract
It is now more than a century since Albert Calmette from the Institut Pasteur changed the world of envenomation by demonstrating that antibodies raised against animal venoms have the ability to treat human victims of previously fatal bites or stings. Moreover, the research initiated at that time effectively launched the discipline of toxicology, first leading to the search for toxic venom components, followed by the demonstration of venoms that also contained compounds of therapeutic value. Interest from pharmaceutical companies to treat envenomation is, however, declining, mainly for economic reasons, and hence, the World Health Organization has reclassified this public health issue to be a highest priority concern. While the production, storage, and safety of antivenom sera suffer from major inconveniences, alternative chemical and technological approaches to the problem of envenomation need to be considered that bypass the use of antibodies for toxin neutralization. Herein, we review an emerging strategy that relies on the use of aptamers and discuss how close—or otherwise—we are to finding a viable alternative to the use of antibodies for the therapy of human envenomation.
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Benjamin JM, Abo BN, Brandehoff N. Review Article: Snake Envenomation in Africa. CURRENT TROPICAL MEDICINE REPORTS 2020. [DOI: 10.1007/s40475-020-00198-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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Chippaux JP, Massougbodji A, Habib AG. The WHO strategy for prevention and control of snakebite envenoming: a sub-Saharan Africa plan. J Venom Anim Toxins Incl Trop Dis 2019; 25:e20190083. [PMID: 31839803 PMCID: PMC6892564 DOI: 10.1590/1678-9199-jvatitd-2019-0083] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2019] [Accepted: 11/08/2019] [Indexed: 11/22/2022] Open
Abstract
Snakebite is a critical public health issue in tropical countries, particularly in Africa, where 20% of snakebites globally occur. In 2017, the WHO added snakebite envenoming to the category A of neglected tropical diseases. In 2019, thanks to broad institutional and international NGO support, including strong mobilization of African experts and governments, WHO launched a strategy for prevention and control of snakebite envenoming with more ambitious goals. In sub-Saharan Africa, accessibility of antivenoms and symptomatic, adjuvant or replacement therapy is a priority. Several antivenoms are available but their evaluation has not been properly carried out and they remain expensive. To date, there are no manufacturers of antivenom in sub-Saharan Africa (except in South Africa), which requires their importation from other continents. The lack of experience in antivenom choice and its use by health authorities, health personnel and population largely explains the shortage in sub-Saharan Africa. The deficiency of epidemiological data does not allow the implementation of appropriate and efficient care. It is crucial to strengthen the health system which does not have the necessary means for emergency management in general and envenoming in particular. Providing peripheral health centers with antivenoms would decrease complications and deaths. The motivation of communities at risk, identified through the epidemiological data, would be to reduce the delay in consultation that is detrimental to the efficiency of treatment. Partnerships need to be coordinated to optimize resources from international institutions, particularly African ones, and share the burden of treatment costs among all stakeholders. We propose here a project of progressive implementation of antivenom manufacturing in sub-Saharan Africa. The various steps, from the supply of appropriate venoms to the production of purified specific antibodies and vial filling, would be financed by international, regional and local funding promoting technology transfer from current manufacturers compensated by interest on the sale of antivenoms.
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Affiliation(s)
- Jean-Philippe Chippaux
- Centre de Recherche d'Île de France, Institut de recherche pour le développement (IRD), Paris, France.,Center for Translational Science, Pasteur Institute, Paris, Île-de-France, France
| | | | - Abdulrazaq G Habib
- Department of Medicine, College of Health Sciences, Bayero University Kano (BUK), Kano, Nigeria
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