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Alfa-Ibrahim Adio A, Malami I, Lawal N, Jega AY, Abubakar B, Bello MB, Ibrahim KG, Abubakar MB, Abdussamad A, Imam MU. Neurotoxic snakebites in Africa: Clinical implications, therapeutic strategies, and antivenom efficacy. Toxicon 2024; 247:107811. [PMID: 38917892 DOI: 10.1016/j.toxicon.2024.107811] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2024] [Revised: 05/23/2024] [Accepted: 06/16/2024] [Indexed: 06/27/2024]
Abstract
Snakebite is a significant health concern in Africa, particularly due to neurotoxic envenomation which can lead to neuromuscular paralysis and respiratory failure. In Nigeria, snakes from the Elapidae family are a notable cause of envenomation cases, though these incidents are underreported. This review examined case reports of neurotoxic envenomation in Africa, highlighting the clinical impacts and the efficacy of available antivenoms. Preclinical studies showed that the polyvalent antivenom from the South African Institute for Medical Research (SAIMR) was highly effective against neurotoxicity with a protective efficacy (R) of 1346.80 mg/mL, while clinical assessment emphasized the need for high-dose antivenom therapy along with supportive measures like mechanical ventilation. Unlike hemorrhagic envenomation, where antivenom promptly resolves bleeding, neurotoxic cases often require additional interventions. The review underscores the necessity for tailored approaches in antivenom therapy to address the complexities of neurotoxic snakebites and reduce their public health burden in Africa.
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Affiliation(s)
- Abdulbaki Alfa-Ibrahim Adio
- Centre for Advanced Medical Research and Training, Usmanu Danfodiyo University, Sokoto, Nigeria; Department of Biochemistry and Molecular Biology, Faculty of Chemical and Life Sciences, Usmanu Danfodiyo University, Sokoto, Nigeria
| | - Ibrahim Malami
- Centre for Advanced Medical Research and Training, Usmanu Danfodiyo University, Sokoto, Nigeria; Department of Pharmacognosy and Ethnopharmacy, Faculty of Pharmaceutical Sciences, Usmanu Danfodiyo University, Sokoto, Nigeria
| | - Nafiu Lawal
- Centre for Advanced Medical Research and Training, Usmanu Danfodiyo University, Sokoto, Nigeria; Department of Veterinary Microbiology, Faculty of Veterinary Medicine, Usmanu Danfodiyo University, Sokoto, Nigeria
| | - Amina Yusuf Jega
- Department of Pharmaceutical and Medicinal Chemistry, Faculty of Pharmaceutical Sciences, Usmanu Danfodiyo University, Sokoto, Nigeria
| | - Bilyaminu Abubakar
- Centre for Advanced Medical Research and Training, Usmanu Danfodiyo University, Sokoto, Nigeria; Department of Pharmacology and Toxicology, Faculty of Pharmaceutical Sciences, Usmanu Danfodiyo University, Sokoto, Nigeria
| | - Muhammad Bashir Bello
- Centre for Advanced Medical Research and Training, Usmanu Danfodiyo University, Sokoto, Nigeria; Department of Veterinary Microbiology, Faculty of Veterinary Medicine, Usmanu Danfodiyo University, Sokoto, Nigeria; Vaccine Development Unit, Infectious Disease Research Development, King Abdullah International Medical Research Center, Riyadh, Saudi Arabia
| | - Kasimu Ghandi Ibrahim
- Centre for Advanced Medical Research and Training, Usmanu Danfodiyo University, Sokoto, Nigeria; Department of Basic Medical and Dental Sciences, Faculty of Dentistry, Zarqa University, P.O. Box 2000, Zarqa, 13110, Jordan; Department of Physiology, Faculty of Basic Medical Sciences, College of Health Sciences, Usmanu Danfodiyo University, Sokoto, Nigeria
| | - Murtala Bello Abubakar
- Centre for Advanced Medical Research and Training, Usmanu Danfodiyo University, Sokoto, Nigeria; Department of Physiology, Faculty of Basic Medical Sciences, College of Health Sciences, Usmanu Danfodiyo University, Sokoto, Nigeria
| | - Abdussamad Abdussamad
- Department of Veterinary Physiology and Biochemistry, Faculty of Veterinary Medicine, Bayero University, Kano, Nigeria
| | - Mustapha Umar Imam
- Centre for Advanced Medical Research and Training, Usmanu Danfodiyo University, Sokoto, Nigeria; Department of Medical Biochemistry, Faculty of Basic Medical Sciences, College of Health Sciences, Usmanu Danfodiyo University, Sokoto, Nigeria.
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Shen Y, Hu S, Bao S, Tu M. Clinical characteristics of snakebite patients attending a tertiary hospital in Hangzhou, southeast China. Trans R Soc Trop Med Hyg 2024; 118:287-292. [PMID: 38073610 DOI: 10.1093/trstmh/trad087] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Revised: 08/01/2023] [Accepted: 11/24/2023] [Indexed: 04/07/2024] Open
Abstract
BACKGROUND Venomous snakebite is a neglected yet an important public health problem in China, and few studies have focused on them so far. The aim of this study is to investigate clinical characteristics of snakebites patients in a tertiary hospital in Hangzhou, southeast China. METHODS A total of 416 snakebite cases were included in this retrospective study. The data were collected from the medical records including demographics, clinical manifestations, management and outcomes. RESULTS Of the 416 patients with venomous snakebites, 248 were male, and the average age was 54.6 years. The majority of cases occurred in rural in May to September. Out of all the venomous bites, Gloydius brevicaudus accounted for the highest percentage (55.3%). Hands were the most vulnerable site to snakebites (47.4%). Patients had clinical manifestations of pain (100%), swelling (100%), wound necrosis (25.7%), hemorrhagic blister (18.3%), and blister (8.7%). Three hundred and ninety-two patients received antivenom administration, and most were treated within six hours after bites. Twenty-six patients received surgical treatments, and 90 patients developed venom-induced consumption coagulopathy. No deaths have occurred in this study. CONCLUSION Hangzhou is one of the regions with high affecting of snakebites in China. The results of this study will increase the understanding of the clinical characteristics of venomous snakebites in Hangzhou area.
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Affiliation(s)
- Yuchen Shen
- Department of Dermatology, Hangzhou TCM Hospital Affiliated to Zhejiang Chinese Medical University, Hangzhou, Zhejiang, People's Republic of China
| | - Sipin Hu
- Department of Vascular Surgery, Tongde Hospital of Zhejiang Province, Hangzhou, Zhejiang, People's Republic of China
| | - Shuhua Bao
- Department of Clinical Laboratory, Hangzhou TCM Hospital Affiliated to Zhejiang Chinese Medical University, Hangzhou, Zhejiang, People's Republic of China
| | - Mengyun Tu
- Department of Clinical Laboratory, Hangzhou TCM Hospital Affiliated to Zhejiang Chinese Medical University, Hangzhou, Zhejiang, People's Republic of China
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Gutiérrez JM, Bolon I, Borri J, Ruiz de Castañeda R. Broadening the research landscape in the field of snakebite envenoming: Towards a holistic perspective. Toxicon 2023; 233:107279. [PMID: 37659665 DOI: 10.1016/j.toxicon.2023.107279] [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: 08/01/2023] [Revised: 08/29/2023] [Accepted: 08/30/2023] [Indexed: 09/04/2023]
Abstract
Snakebite envenoming (SBE) is a neglected tropical disease that kills and maims hundreds of thousands of people yearly, particularly in impoverished rural settings of the Global South. Understanding the complexity of SBE and tackling this disease demands a transdisciplinary, One Health approach. There is a long-standing research tradition on SBE in toxinology and human medicine. In contrast, other disciplines, such as veterinary medicine or social sciences, still need to be better developed in this field, especially in countries with a high incidence of SBE. Broadening the disciplinary landscape, connecting various research approaches, methods, and data across disciplines and sectors, and engaging with communities affected by SBE in implementing evidence-based solutions are needed. This review summarizes areas that require strengthening to better understand the complexity of SBE and to generate a robust body of knowledge to be translated into effective public health interventions.
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Affiliation(s)
- José María Gutiérrez
- Instituto Clodomiro Picado, Facultad de Microbiología, Universidad de Costa Rica, San José, Costa Rica.
| | - Isabelle Bolon
- Institute of Global Health, Department of Community Health and Medicine, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | | | - Rafael Ruiz de Castañeda
- Institute of Global Health, Department of Community Health and Medicine, Faculty of Medicine, University of Geneva, Geneva, Switzerland
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Dajel TB, Abubakar SB, Dan-Amarya NM, Azi NA, Mu'azu S, Hamza M, Iliyasu G, Gwarzo MY, Habib AG. A prospective observational phase IV study on effectiveness of animal derived polyclonal antibody antivenoms against West African carpet viper (Echis romani) induced coagulopathy and mortality. Toxicon 2023:107211. [PMID: 37393958 DOI: 10.1016/j.toxicon.2023.107211] [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: 05/05/2023] [Revised: 06/19/2023] [Accepted: 06/29/2023] [Indexed: 07/04/2023]
Abstract
Conventional polyclonal antibody antivenoms are the mainstay of snakebite therapy. They have not been proven to be efficacious in randomized placebo controlled clinical trials among severely envenomed patients. There is also paucity of evidence on effectiveness especially in routine use. The current study evaluated their effectiveness in post marketing use among those managed with and without antivenom as regards to reversal of venom induced coagulopathy defined using the 20 min Whole Blood Clotting Test [20WBCT] and in averting death. The effectiveness of antivenom was evaluated among 5467 patients predominantly envenomed by the West African carpet viper (Echis romani) at 3 hospitals in Nigeria from 2021 to 2022. Two antivenoms Echitab G (EG) and Echitab ICP Plus (EP) were able to restore normal clotting within 6 h of administration in 58.0% [95% Confidence Interval (95%CI)] (95%CI:51.2-64.5%) and 91.7% (95%CI:90.4-93.0%) of patients respectively. They were able to restore normal clotting within 24 h of administration in 96.9% (95%CI:94.0-98.7%) and 99.0% (95%CI:98.4-99.4%) of patients respectively. The Odds Ratio [OR (95%CI)] of dying among patients with positive 20WBCT who were treated with ≥1 vial of either EG or EP compared to those not treated was 0.06 (0.02-0.23) and 0.07 (0.03-0.15) respectively. This equated to antivenom protection against in-hospital mortality of 93-94% among patients with confirmed coagulopathy though the benefit appeared abrogated among those without coagulopathy. The untreated natural mortality was 15.94% (95%CI:8.24-26.74%) without antivenom therapy while the overall mortality was 84/5105 (1.65%; 95%CI:1.32-2.03%. The Number Needed to Treat (NNT) to avert a death was 7 patients among patients with coagulopathy. Antivenoms were safe with mild early adverse reactions observed among 2.6% (95%CI:2.13-3.08%) of antivenom recipients. Polyclonal antibody antivenoms are effective and safe for treating coagulopathic envenomed patients in Nigeria.
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Affiliation(s)
- Titus B Dajel
- Comprehensive Health Center Zamko, Langtang, Plateau state, Nigeria
| | - Saidu B Abubakar
- Snakebite Hospital & Research Center, Kaltungo, Gombe state, Nigeria
| | | | - Nyam A Azi
- Comprehensive Health Center Zamko, Langtang, Plateau state, Nigeria
| | | | - Muhammad Hamza
- Venom Antivenom Research Project (VASP), Bayero University Kano, Kano state, Nigeria
| | - Garba Iliyasu
- Venom Antivenom Research Project (VASP), Bayero University Kano, Kano state, Nigeria
| | - Muhammad Y Gwarzo
- Venom Antivenom Research Project (VASP), Bayero University Kano, Kano state, Nigeria
| | - Abdulrazaq G Habib
- Venom Antivenom Research Project (VASP), Bayero University Kano, Kano state, Nigeria.
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Hsu JY, Chiang SO, Yang CC, Hsieh TW, Chung CJ, Mao YC. Nationwide and long-term epidemiological research of snakebite envenomation in Taiwan during 2002-2014 based on the use of snake antivenoms: A study utilizing National Health Insurance Database. PLoS Negl Trop Dis 2023; 17:e0011376. [PMID: 37289739 DOI: 10.1371/journal.pntd.0011376] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2023] [Accepted: 05/12/2023] [Indexed: 06/10/2023] Open
Abstract
INTRODUCTION In Taiwan, six venomous snake species with medical importance have been found; however, long-term epidemiological data of snakebite envenomation (SBE) is lacking. This study aimed to explore the epidemiology of SBE based on the distribution and use of different antivenoms in different parts of Taiwan to facilitate the development of prevention strategies and resource allocation. METHODS AND RESULTS This retrospective study was conducted using the Taiwan National Health Insurance Research Database from 2002 to 2014. A total of 12,542 patients were treated with antivenoms. The directly standardized cumulative incidence was 3.6 cases per 100,000 individuals based on the 2000 World Standard Population. The incidence of SBEs peaked in the summer (35.9%). The relative risk (RR) of male patients versus female patients was 2.5 (p < 0.0001). The RRs of patients aged 18-64 and ≥65 years versus those aged <18 years were 6.0 (p < 0.0001) and 14.3 (p < 0.0001), respectively. Furthermore, the RR of eastern Taiwan versus northern Taiwan was 6.8 (p < 0.0001). The RR of agricultural workers versus laborers was 5.5 (p < 0.0001). Compared with patients envenomed by Trimeresurus stejnegeri stejnegeri or Protobothrops mucrosquamatus, those envenomed by Naja atra or Bungarus multicinctus multicinctus were more likely to occur in central (adjusted odds ratio [aOR] = 2.6, p < 0.0001) or southern (aOR = 3.2, p < 0.0001) Taiwan, but less frequently among agricultural workers (aOR = 0.6, p < 0.0001). The overall case-fatality rate was 0.11%. CONCLUSIONS Among Asian countries, Taiwan had low incidence and case-fatality rates of SBE. Risk factors included male gender, old age, summer season, being in eastern Taiwan, and being an agricultural worker. Differences of the epidemiological findings between snake species should be focused on when developing strategies for snakebite prevention.
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Affiliation(s)
- Jen-Yu Hsu
- Department of Occupational Medicine and Clinical Toxicology, Taipei Veterans General Hospital, Taipei, Taiwan
- Office of Preventive Medicine, Centers for Disease Control, Ministry of Health and Welfare, Taipei, Taiwan
- School of Medicine, College of Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Shu-O Chiang
- ESTAT Statistical Consulting Co., Ltd., Taipei, Taiwan
| | - Chen-Chang Yang
- Department of Occupational Medicine and Clinical Toxicology, Taipei Veterans General Hospital, Taipei, Taiwan
- Institute of Environmental and Occupational Health Sciences, College of Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Tan-Wen Hsieh
- Institute of Public Health, College of Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Chi-Jung Chung
- Department of Public Health, College of Public Health, China Medical University, Taichung, Taiwan
- Department of Medical Research, China Medical University Hospital, Taichung, Taiwan
| | - Yan-Chiao Mao
- PhD Program in Medical Biotechnology, College of Medical Science and Technology, Taipei Medical University, Taipei, Taiwan
- School of Medicine, National Defense Medical Center, Taipei, Taiwan
- Department of Post-Baccalaureate Medicine, College of Medicine, National Chung Hsing University, Taichung, Taiwan
- Division of Clinical Toxicology, Department of Emergency Medicine, Taichung Veterans General Hospital, Taichung, Taiwan
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Dalhat MM, Potet J, Mohammed A, Chotun N, Tesfahunei HA, Habib AG. Availability, accessibility and use of antivenom for snakebite envenomation in Africa with proposed strategies to overcome the limitations. Toxicon X 2023; 18:100152. [PMID: 36936749 PMCID: PMC10015232 DOI: 10.1016/j.toxcx.2023.100152] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Revised: 02/10/2023] [Accepted: 02/16/2023] [Indexed: 02/27/2023] Open
Abstract
Africa remains one of the regions with the highest incident and burden of snakebite. The goal of the World Health Organization to halve the global burden of snakebite by 2030 can only be achieved if sub-optimal access to antivenoms in the most affected regions is addressed. We identified upstream, midstream, and downstream factors along the antivenom value chain that prevent access to antivenoms in the African region. We identified windows of opportunities that could be utilized to ensure availability, accessibility, and affordability for snakebite endemic populations in Africa. These include implementation of multicomponent strategies such as intensified advocacy, community engagement, healthcare worker trainings, and leveraging the institutional and governance structure provided by African governments to address the challenges identified.
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Affiliation(s)
| | - Julien Potet
- Neglected Tropical Diseases, Medecins Sans Frontieres, Paris, France
| | - Abdulaziz Mohammed
- Division of Disease Control and Prevention, Africa Centres for Disease Control and Prevention, Ethiopia
| | - Nafiisah Chotun
- Division of Disease Control and Prevention, Africa Centres for Disease Control and Prevention, Ethiopia
| | - Hanna Amanuel Tesfahunei
- Division of Disease Control and Prevention, Africa Centres for Disease Control and Prevention, Ethiopia
| | - Abdulrazaq Garba Habib
- Infectious and Tropical Diseases Unit, Department of Medicine, Bayero University, Kano, Nigeria
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Hamza M, Dajel TB, Abubakar SB, Hamza AS, Abdullahi HL, Iliyasu G, Habib AG. Performance of the 20 minutes Whole Blood Clotting Test in detection, monitoring and antivenom therapy of West African Carpet viper (Echis romani) envenoming in resource constrained settings in Nigeria. Toxicon 2023; 224:107025. [PMID: 36640811 DOI: 10.1016/j.toxicon.2023.107025] [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: 11/16/2022] [Revised: 12/26/2022] [Accepted: 01/10/2023] [Indexed: 01/13/2023]
Abstract
The 20 minutes Whole Blood Clotting Test (20WBCT) was evaluated in 1541 snakebite patients at 3 hospitals in Nigeria. It was useful in detection, monitoring, guiding antivenom therapy and prognostication of coagulopathy, with initial sensitivity of 84.7% (95%CI:82.7-86.5%) and specificity of 64.3% (95%CI:50.4-76.7%) compared to clinical envenoming. It led to correct decisions regarding administration or withholding antivenom in 97.93% of patients. The proportion of carpet viper (Echis romani) envenomed patients who restored clotting rose steadily following effective antivenom therapy. Patients with positive 20WBCT had severer envenoming, required more blood transfusion, had longer hospital stay and derived higher antivenom protection against death from carpet viper. However, there was no association between positive 20WBCT and fatality or complications.
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Affiliation(s)
| | - Titus B Dajel
- Comprehensive Health Center Zamko, Langtang, Plateau state, Nigeria
| | - Saidu B Abubakar
- Snakebite Hospital & Research Center, Kaltungo, Gombe state, Nigeria
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Halliru N, Badamasi MM, Tudunwada IY, Dajel TB, Abubakar SB, Hamza AS, Oluwashola SB, Nalado NK, Dahiru M, Na’abdu I, Saleh UN, Daiyab AM, Mohammed SA, Iliyasu G, Muhammad H, Habib AG. Epidemiologic and spatiotemporal study on access to snakebite care in Northern Nigeria. TOXIN REV 2023. [DOI: 10.1080/15569543.2023.2177873] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Affiliation(s)
- Naziru Halliru
- Geo-Referenced Infrastructure and Demographic Data for Development (GRID3) Nigeria, CIESIN, Columbia Climate School, Columbia University, New York, NY, USA
| | - Murtala M. Badamasi
- Geographic Information Systems (GIS) Lab, Center for Dryland Agriculture, Bayero University Kano, Kano, Nigeria
| | | | - Titus B. Dajel
- Comprehensive Health Center Zamko, Jos University Teaching Hospital, Langtang, Plateau state, Nigeria
| | | | | | | | - Nasiru K. Nalado
- Zonal Advanced Space Technology Applications Laboratory, Kano, Nigeria
| | - Muhammad Dahiru
- Zonal Advanced Space Technology Applications Laboratory, Kano, Nigeria
| | - Ibrahim Na’abdu
- Geographic Information Systems (GIS) Lab, Center for Dryland Agriculture, Bayero University Kano, Kano, Nigeria
| | - Umar N. Saleh
- Geographic Information Systems (GIS) Lab, Center for Dryland Agriculture, Bayero University Kano, Kano, Nigeria
| | | | | | - Garba Iliyasu
- Infectious & Tropical Diseases Unit, Bayero University Kano, Kano, Nigeria
| | - Hamza Muhammad
- Infectious & Tropical Diseases Unit, Bayero University Kano, Kano, Nigeria
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Patikorn C, Ismail AK, Zainal Abidin SA, Othman I, Chaiyakunapruk N, Taychakhoonavudh S. Potential economic and clinical implications of improving access to snake antivenom in five ASEAN countries: A cost-effectiveness analysis. PLoS Negl Trop Dis 2022; 16:e0010915. [PMID: 36383562 PMCID: PMC9668136 DOI: 10.1371/journal.pntd.0010915] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Accepted: 10/28/2022] [Indexed: 11/17/2022] Open
Abstract
Background Despite domestic production of antivenoms in the Association of Southeast Asian Nations (ASEAN) countries, not all victims with snakebite envenomings indicated for antivenom received the appropriate or adequate effective dose of antivenom due to insufficient supply and inadequate access to antivenoms. We aimed to conduct a cost-effectiveness analysis to project the potential economic and clinical impact of improving access to antivenoms when all snakebite envenomings in ASEAN countries were hypothetically treated with geographically appropriate antivenoms. Methodology Using a decision analytic model with input parameters from published literature, local data, and expert opinion, we projected the impact of “full access” (100%) to antivenom, compared to “current access” in five most impacted ASEAN countries, including Indonesia (10%), Philippines (26%), Vietnam (37%), Lao PDR (4%), and Myanmar (64%), from a societal perspective with a lifetime time horizon. Sensitivity analyses were performed. Principal findings In base-case analyses, full access compared to current access to snake antivenom in the five countries resulted in a total of 9,362 deaths averted (-59%), 230,075 disability-adjusted life years (DALYs) averted (-59%), and cost savings of 1.3 billion USD (-53%). Incremental cost-effectiveness ratios (ICERs) of improving access to antivenom found higher outcomes but lower costs in all countries. Probabilistic sensitivity analyses of 1,000 iterations found that 98.1–100% of ICERs were cost-saving. Conclusion/Significance Improving access to snake antivenom will result in cost-saving for ASEAN countries. Our findings emphasized the importance of further strengthening regional cooperation, investment, and funding to improve the situation of snakebite victims in ASEAN countries. In the Association of Southeast Asian Nations (ASEAN) countries, it was estimated that annually there were 242,648 snakebite victims in ASEAN of which 15,909 victims were dead. Despite domestic production of antivenoms in ASEAN countries, not all victims with snakebite envenomings indicated for antivenom received the appropriate or adequate effective dose of antivenom due to insufficient supply and inadequate access to antivenoms. Especially in Indonesia, Philippines, Vietnam, Lao PDR, and Myanmar, where 4–64% of victims who needed antivenoms were treated with antivenoms. We conducted a cost-effectiveness analysis to project the potential economic and clinical impact of improving access to antivenoms when all victims with snakebite envenomings in the five most impacted ASEAN countries were hypothetically treated with geographically appropriate antivenoms. Improving access to snake antivenom to the full level of access compared to the current level in the five ASEAN countries resulted in a total of 9,362 deaths averted (-59%), 230,075 disability-adjusted life years (DALYs) averted (-59%), and cost savings of 1.3 billion USD (-53%). Our study demonstrated improving access to snake antivenom from the current to the full level of access in ASEAN countries is a cost-saving strategy. Our findings emphasized the importance of further strengthening regional cooperation, investment, and funding to improve the situation of snakebite victims in ASEAN countries to reach the ultimate goal where all victims with snakebite envenoming needing antivenom adequately received the geographically appropriate antivenoms.
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Affiliation(s)
- Chanthawat Patikorn
- Department of Social and Administrative Pharmacy, Faculty of Pharmaceutical Sciences, Chulalongkorn University, Bangkok, Thailand
- Department of Pharmacotherapy, College of Pharmacy, University of Utah, Salt Lake City, Utah, United States of America
| | - Ahmad Khaldun Ismail
- Department of Emergency Medicine, Faculty of Medicine, Universiti Kebangsaan Malaysia, Jalan Yaacob Latif, Bandar Tun Razak, Kuala Lumpur, Malaysia
| | - Syafiq Asnawi Zainal Abidin
- Jeffrey Cheah School of Medicine and Health Sciences, Monash University Malaysia, Jalan Lagoon Selatan, Bandar Sunway, Selangor, Malaysia
| | - Iekhsan Othman
- Jeffrey Cheah School of Medicine and Health Sciences, Monash University Malaysia, Jalan Lagoon Selatan, Bandar Sunway, Selangor, Malaysia
| | - Nathorn Chaiyakunapruk
- Department of Pharmacotherapy, College of Pharmacy, University of Utah, Salt Lake City, Utah, United States of America
- IDEAS Center, Veterans Affairs Salt Lake City Healthcare System, Salt Lake City, Utah, United States of America
- School of Pharmacy, Monash University Malaysia, Selangor, Malaysia
- * E-mail: (NC); (ST)
| | - Suthira Taychakhoonavudh
- Department of Social and Administrative Pharmacy, Faculty of Pharmaceutical Sciences, Chulalongkorn University, Bangkok, Thailand
- * E-mail: (NC); (ST)
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Montoya-Vargas W, Gutiérrez JM, Quesada-Morúa MS, Morera-Huertas J, Rojas C, Leon-Salas A. Preliminary assessment of antivenom availability and management in the public health system of Costa Rica: An analysis based on a survey to pharmacists in public health facilities. Toxicon X 2022; 16:100139. [PMID: 36325535 PMCID: PMC9619377 DOI: 10.1016/j.toxcx.2022.100139] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2022] [Revised: 10/18/2022] [Accepted: 10/21/2022] [Indexed: 12/12/2022] Open
Abstract
Availability and accessibility of safe and effective antivenoms are key elements for the successful treatment of snakebite envenoming (SBE). This study provides a preliminary analysis on the way antivenoms are managed by the public health system in Costa Rica and on the role played by pharmacists in the overall management of antivenoms. This was an observational, cross-sectional study based on an online survey sent to pharmacists working at Caja Costarricense de Seguro Social (Costa Rican Social Security System; CCSS) in different locations in Costa Rica. Characteristics and location of health facilities, as well as antivenom availability and management details, were analyzed. Responses from a total of 96 pharmacists, corresponding to 55 different healthcare facilities, were included in this study. Most respondents worked at pharmacies located in urban communities (69.0%) and in the secondary level of care, which includes clinics, and regional and peripheral hospitals (55.2%). Overall, participants reported antivenom availability at all levels of care and in centers having various operating schedules, although they were not available in some facilities in regions where SBE is uncommon or do not attend SBE cases because of the proximity of more complex health centers. On average, the stocks of anticoral and polyvalent antivenoms per health facility were compatible with the dose of antivenom required for treating a SBE case. More than half of participants reported knowing the availability of protocols for the management of SBE and the correct use of antivenom at their healthcare facilities. Of the total respondents, 49% agreed on possessing all the resources needed for the correct management of these medicines at their facilities, and 65.6% indicated that they know the procedures for antivenom storage and management. Our findings provide a first description of the availability of antivenoms in the public health system of Costa Rica, including the primary care level. Results also underscore the perceived role of participating pharmacists in the management of these life-saving drugs and the need to improve their knowledge on this topic.
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Affiliation(s)
- Wendy Montoya-Vargas
- Instituto de Investigaciones Farmacéuticas (INIFAR), Facultad de Farmacia, Universidad de Costa Rica, Costa Rica
| | - José María Gutiérrez
- Instituto Clodomiro Picado, Facultad de Microbiología, Universidad de Costa Rica, San José, 11501, Costa Rica
| | - María Soledad Quesada-Morúa
- Instituto de Investigaciones Farmacéuticas (INIFAR), Facultad de Farmacia, Universidad de Costa Rica, Costa Rica
| | | | - Carolina Rojas
- Facultad de Farmacia, Universidad de Costa Rica, Costa Rica
| | - Angie Leon-Salas
- Instituto de Investigaciones Farmacéuticas (INIFAR), Facultad de Farmacia, Universidad de Costa Rica, Costa Rica,Corresponding author. .
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Patikorn C, Blessmann J, Nwe MT, Tiglao PJG, Vasaruchapong T, Maharani T, Doan UV, Zainal Abidin SA, Ismail AK, Othman I, Taychakhoonavudh S, Chaiyakunapruk N. Estimating economic and disease burden of snakebite in ASEAN countries using a decision analytic model. PLoS Negl Trop Dis 2022; 16:e0010775. [PMID: 36170270 PMCID: PMC9518918 DOI: 10.1371/journal.pntd.0010775] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2022] [Accepted: 08/30/2022] [Indexed: 12/24/2022] Open
Abstract
Background
Understanding the burden of snakebite is crucial for developing evidence-informed strategies to pursue the goal set by the World Health Organization to halve morbidity and mortality of snakebite by 2030. However, there was no such information in the Association of Southeast Asian Nations (ASEAN) countries.
Methodology
A decision analytic model was developed to estimate annual burden of snakebite in seven countries, including Malaysia, Thailand, Indonesia, Philippines, Vietnam, Lao PDR, and Myanmar. Country-specific input parameters were sought from published literature, country’s Ministry of Health, local data, and expert opinion. Economic burden was estimated from the societal perspective. Costs were expressed in 2019 US Dollars (USD). Disease burden was estimated as disability-adjusted life years (DALYs). Probabilistic sensitivity analysis was performed to estimate a 95% credible interval (CrI).
Principal findings
We estimated that annually there were 242,648 snakebite victims (95%CrI 209,810–291,023) of which 15,909 (95%CrI 7,592–33,949) were dead and 954 (95%CrI 383–1,797) were amputated. We estimated that 161,835 snakebite victims (69% of victims who were indicated for antivenom treatment) were not treated with antivenom. Annual disease burden of snakebite was estimated at 391,979 DALYs (95%CrI 187,261–836,559 DALYs) with total costs of 2.5 billion USD (95%CrI 1.2–5.4 billion USD) that were equivalent to 0.09% (95%CrI 0.04–0.20%) of the region’s gross domestic product. >95% of the estimated burdens were attributed to premature deaths.
Conclusion/Significance
The estimated high burden of snakebite in ASEAN was demonstrated despite the availability of domestically produced antivenoms. Most burdens were attributed to premature deaths from snakebite envenoming which suggested that the remarkably high burden of snakebite could be averted. We emphasized the importance of funding research to perform a comprehensive data collection on epidemiological and economic burden of snakebite to eventually reveal the true burden of snakebite in ASEAN and inform development of strategies to tackle the problem of snakebite.
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Affiliation(s)
- Chanthawat Patikorn
- Department of Social and Administrative Pharmacy, Faculty of Pharmaceutical Sciences, Chulalongkorn University, Bangkok, Thailand
| | - Jörg Blessmann
- Department of Implementation Research, Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany
| | | | - Patrick Joseph G. Tiglao
- Department of Emergency Medicine, Eastern Visayas Regional Medical Center, Tacloban City, Philippines
- Philippine Toxinology Society, Incorporated, Manila, Philippines
- Department of Emergency Medicine, University of the Philippines-Manila, Philippine General Hospital, Manila, Philippines
- Department of Emergency Medicine, Corazon Locsin Montelibano Memorial Regional Hospital, Bacolod City, Negros Occidental, Philippines
| | - Taksa Vasaruchapong
- Snake Farm, Queen Saovabha Memorial Institute, The Thai Red Cross Society, Bangkok, Thailand
| | - Tri Maharani
- National Institute Research and Development, Ministry of Health, Jakarta, Indonesia
| | - Uyen Vy Doan
- Division of Medical Toxicology, Cho Ray Hospital, Ho Chi Minh City, Vietnam
| | - Syafiq Asnawi Zainal Abidin
- Jeffrey Cheah School of Medicine and Health Sciences, Monash University Malaysia, Bandar Sunway, Selangor, Malaysia
| | - Ahmad Khaldun Ismail
- Department of Emergency Medicine, Faculty of Medicine, Universiti Kebangsaan Malaysia, Bandar Tun Razak, Kuala Lumpur, Malaysia
| | - Iekhsan Othman
- Jeffrey Cheah School of Medicine and Health Sciences, Monash University Malaysia, Bandar Sunway, Selangor, Malaysia
| | - Suthira Taychakhoonavudh
- Department of Social and Administrative Pharmacy, Faculty of Pharmaceutical Sciences, Chulalongkorn University, Bangkok, Thailand
- * E-mail: (ST); (NC)
| | - Nathorn Chaiyakunapruk
- Department of Pharmacotherapy, College of Pharmacy, University of Utah, Salt Lake City, Utah, United States of America
- IDEAS Center, Veterans Affairs Salt Lake City Healthcare System, Salt Lake City, Utah, United States of America
- School of Pharmacy, Monash University Malaysia, Selangor, Malaysia
- * E-mail: (ST); (NC)
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12
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Zeng ZY, Huang PY, Du JY, Liu YX, Guo SG, Zeng LS, Zhang CC, Li Y. Effect of Agkistrodon halys antivenom in patients bit by green pit viper and the prognostic role of the disease - a retrospective cohort study. Clin Toxicol (Phila) 2022; 60:808-817. [PMID: 35225104 DOI: 10.1080/15563650.2022.2041200] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
BACKGROUND AND AIMS In Mainland China and Hong Kong, health authorities utilize Agkistrodon halys antivenom in the treatment of patients who sustained bites from green pit vipers. However, the treatment benefit of Agkistrodon halys antivenom among such patients is still controversial. The purpose of this study is to evaluate the coagulation parameters normalization time of Agkistrodon halys antivenom in patients who sustained green pit viper bites and explore independent risk factors of patient prognosis. METHODS Data were extracted from the Donghua Hospital Information System. Comparison of the two groups of patients - who used antivenom (GPUA) and who did not use antivenom (GPNUA) were performed using stratified analysis, univariate and multivariate ordered logistic regression models to evaluate the coagulation parameters normalization time. Univariate and multivariate ordered logistic regression models were used to explore independent risk factors of patient prognosis. RESULTS Between the GPUA and GPNUA groups, there is no significant difference in the coagulation parameters normalization time with the treatment of Agkistrodon halys antivenom. GPNUA consumed more cryoprecipitate and platelets and had a lower cost. The patient's severity of the bite, first coagulation profile, and dosages of fresh frozen plasma, platelet, and red cell suspension was found to be risk factors for the normalization time of coagulation parameters. CONCLUSIONS The therapeutic effect of Agkistrodon halys antivenom in green pit vipers bite patients is not quite satisfying. In addition, more attention should be paid to the first coagulation profile, blood clotting factors indices, platelet count (PLT), and hemoglobin when treating such patients.
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Affiliation(s)
- Zhong-Yi Zeng
- Emergency Department, Shenzhen Traditional Chinese Medicine Hospital, Shenzhen, PR China
| | - Pei-Ying Huang
- The Second Clinical Medical College of Guangzhou University of Chinese Medicine, Guangzhou, PR China.,Emergency Department, the Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, PR China
| | - Jia-Yu Du
- Emergency Department, Shenzhen Traditional Chinese Medicine Hospital, Shenzhen, PR China
| | - Yu-Xiang Liu
- Emergency Department, Shenzhen Traditional Chinese Medicine Hospital, Shenzhen, PR China
| | - Shi-Gong Guo
- Department of Rehabilitation Medicine, Southmead Hospital, Bristol, UK
| | - Lin-Sheng Zeng
- Emergency Department, Shenzhen Traditional Chinese Medicine Hospital, Shenzhen, PR China
| | - Cong-Cong Zhang
- Emergency Department, Shenzhen Traditional Chinese Medicine Hospital, Shenzhen, PR China
| | - Yi Li
- Emergency Department, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, Beijing, PR China
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13
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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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14
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Adinortey MB. Botanical treatments for snakebite in rural Ghana: A narrative review. JOURNAL OF ETHNOPHARMACOLOGY 2021; 280:114432. [PMID: 34274442 DOI: 10.1016/j.jep.2021.114432] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2021] [Revised: 06/30/2021] [Accepted: 07/14/2021] [Indexed: 06/13/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE In the countryside, there are some limitations with the use of venom antisera to manage snake bites. Due to poor access to healthcare and as a result of the difficulty in receiving treatment for cases of snake bites, most rural people in Ghana, a West African country, rely on plant medicine as a first aid to manage cases of venomous snakebite. This calls for more research into the species of plants used to medically manage snakebite envenomation. AIM OF THE STUDY This review sought to present plants that are used in managing snakebite cases and also gather data supporting their use. METHODOLOGY This is a systematic search and review of information obtained from textbooks and databases such as PubMed and ScienceDirect between January 1975 and August 2020. RESULTS A search done identified 43 plant species and these were found to belong to 25 taxonomic families with the most frequent ones being, Fabaceae, Euphorbiaceae, Apocynaceae, and Solanaceae. Experimental data gathered indicate that among the many plants identified to be used to manage snakebites, only 5 were found with anti-venom in vitro and in vivo evidence-based data. CONCLUSION Data collated hint that a few plant species identified namely Anacardium occidentale, Euphorbia hirta, Mimosa pudica, Musa paradisiaca and Mangifera indica, work by targeting diverse physiopathological and biochemical processes involved in the clinical manifestations of snakebites. This review has also unearthed knowledge gaps that can form the basis for broad investigations and development of these and other medicinal plants into useful anti-venom medications.
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15
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Ortiz-Prado E, Yeager J, Andrade F, Schiavi-Guzman C, Abedrabbo-Figueroa P, Terán E, Gómez-Barreno L, Simbaña-Rivera K, Izquierdo-Condoy JS. Snake antivenom production in Ecuador: Poor implementation, and an unplanned cessation leads to a call for a renaissance. Toxicon 2021; 202:90-97. [PMID: 34571098 DOI: 10.1016/j.toxicon.2021.09.014] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Revised: 09/21/2021] [Accepted: 09/23/2021] [Indexed: 11/28/2022]
Abstract
Snakebite envenomation is a global health problem. This health problem asymmetrically affects rural populations in developing countries to such an extent that it recently has been listed as a priority neglected tropical disease (NTD). It is estimated that 5.4 million individuals are bitten by snakes each year, causing at least 2.7 million envenomations and more than 100,000 deaths each year. Ecuador has one of the highest snakebite envenomation incidence rates in Latin America, mostly in the coastal and Amazonian provinces. Envenomations in these regions are the result of bites primarily by species of snakes belonging to the Viperidae family. Ecuador was able to locally produce antivenoms, however serious flaws were revealed in the antivenom production process, leading to the decommissioning of the existing facility. In the interest of public health, we have summarized the political and social setbacks experienced by the antivenom serum production plant in Ecuador, while encouraging resuming local production of snake antivenom to improve the responsiveness of the already overburdened health system.
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Affiliation(s)
- Esteban Ortiz-Prado
- OneHealth Global Research Group, Universidad de las Américas, Quito, Ecuador.
| | - Justin Yeager
- Biodiversity, Environment, and Health (BIOMAS), Universidad de las Americas, Quito, Ecuador
| | - Felipe Andrade
- OneHealth Global Research Group, Universidad de las Américas, Quito, Ecuador
| | | | | | - Enrique Terán
- Colegio de Ciencias de la Salud, Universidad San Francisco de Quito, Quito, Ecuador
| | - Lenin Gómez-Barreno
- OneHealth Global Research Group, Universidad de las Américas, Quito, Ecuador
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16
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Hamza M, Knudsen C, Gnanathasan CA, Monteiro W, Lewin MR, Laustsen AH, Habib AG. Clinical management of snakebite envenoming: Future perspectives. Toxicon X 2021; 11:100079. [PMID: 34430847 PMCID: PMC8374517 DOI: 10.1016/j.toxcx.2021.100079] [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: 04/06/2021] [Revised: 06/29/2021] [Accepted: 07/30/2021] [Indexed: 11/18/2022] Open
Abstract
Snakebite envenoming is a major cause of morbidity and mortality in rural communities throughout the tropics. Generally, the main clinical features of snakebites are local swelling, tissue necrosis, shock, spontaneous systemic hemorrhage, incoagulable blood, paralysis, rhabdomyolysis, and acute kidney injury. These clinical manifestations result from complex biochemical venom constituents comprising of cytotoxins, hemotoxins, neurotoxins, myotoxins, and other substances. Timely diagnosis of envenoming and identification of the responsible snake species is clinically challenging in many parts of the world and necessitates prompt and thorough clinical assessment, which could be supported by the development of reliable, affordable, widely-accessible, point-of-care tests. Conventional antivenoms based on polyclonal antibodies derived from animals remain the mainstay of therapy along with supportive medical and surgical care. However, while antivenoms save countless lives, they are associated with adverse reactions, limited potency, and are relatively inefficacious against presynaptic neurotoxicity and in preventing necrosis. Nevertheless, major scientific and technological advances are facilitating the development of new molecular and immunologic diagnostic tests, as well as a new generation of antivenoms comprising human monoclonal antibodies with broader and more potent neutralization capacity and less immunogenicity. Repurposed pharmaceuticals based on small molecule inhibitors (e.g., marimastat and varespladib) used alone and in combination against enzymatic toxins, such as metalloproteases and phospholipase A2s, have shown promise in animal studies. These orally bioavailable molecules could serve as early interventions in the out-of-hospital setting if confirmed to be safe and efficacious in clinical studies. Antivenom access can be improved by the usage of drones and ensuring constant antivenom supply in remote endemic rural areas. Overall, the improvement of clinical management of snakebite envenoming requires sustained, coordinated, and multifaceted efforts involving basic and applied sciences, new technology, product development, effective clinical training, implementation of existing guidelines and therapeutic approaches, supported by improved supply of existing antivenoms.
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Affiliation(s)
- Muhammad Hamza
- Infectious and Tropical Diseases Unit, Bayero University Kano, Nigeria
| | - Cecilie Knudsen
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kongens Lyngby, Denmark
| | | | - Wuelton 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
| | - Matthew R. Lewin
- Center for Exploration and Travel Health, California Academy of Sciences, San Francisco, USA
| | - Andreas H. Laustsen
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kongens Lyngby, Denmark
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17
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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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18
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The Failures of Ethnobotany and Phytomedicine in Delivering Novel Treatments for Snakebite Envenomation. Toxins (Basel) 2020; 12:toxins12120774. [PMID: 33291263 PMCID: PMC7762085 DOI: 10.3390/toxins12120774] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Revised: 12/02/2020] [Accepted: 12/04/2020] [Indexed: 01/12/2023] Open
Abstract
Snakebite envenomation (SBE) is a high-priority, neglected tropical disease. This devastating occupational health hazard disproportionately affects rural farming communities in tropical countries. This is exacerbated by the distribution and densities of venomous snakes, incidence of encounters, and limited access to advanced healthcare, including antivenom. Before the development of antivenom, desperation and spiritual beliefs led patients to experiment with a wide range of traditional treatments. Many of these treatments still survive today, particularly in regions where access to healthcare is limited. Plants are a major source of bioactive molecules, including several lifesaving medications that are widely used to this day. However, much of the research into the use of traditional plant treatments for SBE are limited to preliminary analysis or have focused on techniques used to confirm antibody efficacy that are not suitable for non-antibody-containing treatments. Modern drugs are developed through a robust pharmaceutical drug discovery and development process, which applies as much to SBE as it does to any other disease. This review discusses specifically why research into ethnobotanical practices has failed to identify or develop a novel treatment for SBE and proposes specific approaches that should be considered in this area of research in the future.
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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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Xie C, Slagboom J, Albulescu LO, Somsen GW, Vonk FJ, Casewell NR, Kool J. Neutralising effects of small molecule toxin inhibitors on nanofractionated coagulopathic Crotalinae snake venoms. Acta Pharm Sin B 2020; 10:1835-1845. [PMID: 33163338 PMCID: PMC7606088 DOI: 10.1016/j.apsb.2020.09.005] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2020] [Revised: 09/03/2020] [Accepted: 09/04/2020] [Indexed: 11/29/2022] Open
Abstract
Repurposing small molecule drugs and drug candidates is considered as a promising approach to revolutionise the treatment of snakebite envenoming. In this study, we investigated the inhibiting effects of the small molecules varespladib (nonspecific phospholipase A2 inhibitor), marimastat (broad spectrum matrix metalloprotease inhibitor) and dimercaprol (metal ion chelator) against coagulopathic toxins found in Crotalinae (pit vipers) snake venoms. Venoms from Bothrops asper, Bothrops jararaca, Calloselasma rhodostoma and Deinagkistrodon acutus were separated by liquid chromatography, followed by nanofractionation and mass spectrometry identification undertaken in parallel. Nanofractions of the venom toxins were then subjected to a high-throughput coagulation assay in the presence of different concentrations of the small molecules under study. Anticoagulant venom toxins were mostly identified as phospholipases A2, while procoagulant venom activities were mainly associated with snake venom metalloproteinases and snake venom serine proteases. Varespladib was found to effectively inhibit most anticoagulant venom effects, and also showed some inhibition against procoagulant toxins. Contrastingly, marimastat and dimercaprol were both effective inhibitors of procoagulant venom activities but showed little inhibitory capability against anticoagulant toxins. The information obtained from this study aids our understanding of the mechanisms of action of toxin inhibitor drug candidates, and highlights their potential as future snakebite treatments.
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Key Words
- ACN, acetonitrile
- Antivenom
- CTL, C-type lectins
- Chelators
- DMSO, dimethyl sulfoxide
- Dimercaprol
- FA, formic acid
- HTS, high-throughput screening
- LC, liquid chromatography
- MS, mass spectrometry
- Marimastat
- NOI, no observed inhibition
- Nanofractionation
- PBS, phosphate buffered saline
- PLA2, phospholipase A2
- PN, partly neutralised at 20 μmol/L inhibitor concentrations
- SVMP, snake venom metalloproteinase
- SVSP, snake venom serine protease
- Snakebite
- TIC, total ion current
- Varespladib
- WHO, World Health Organization
- XIC, extracted ion current
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Affiliation(s)
- 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, Amsterdam 1081HV, The Netherlands
- Centre for Analytical Sciences Amsterdam (CASA), Amsterdam 1098 XH, The Netherlands
| | - Julien Slagboom
- Amsterdam Institute of Molecular and Life Sciences, Division of BioAnalytical Chemistry, Department of Chemistry and Pharmaceutical Sciences, Faculty of Science, Vrije Universiteit Amsterdam, Amsterdam 1081HV, The Netherlands
- Centre for Analytical Sciences Amsterdam (CASA), Amsterdam 1098 XH, The Netherlands
| | - Laura-Oana Albulescu
- Centre for Snakebite Research and Interventions, Liverpool School of Tropical Medicine, Liverpool L3 5QA, UK
- Centre for Drugs and Diagnostics, Liverpool School of Tropical Medicine, Liverpool L3 5QA, UK
| | - Govert W. Somsen
- Amsterdam Institute of Molecular and Life Sciences, Division of BioAnalytical Chemistry, Department of Chemistry and Pharmaceutical Sciences, Faculty of Science, Vrije Universiteit Amsterdam, Amsterdam 1081HV, The Netherlands
- Centre for Analytical Sciences Amsterdam (CASA), Amsterdam 1098 XH, The Netherlands
| | - Freek J. Vonk
- Amsterdam Institute of Molecular and Life Sciences, Division of BioAnalytical Chemistry, Department of Chemistry and Pharmaceutical Sciences, Faculty of Science, Vrije Universiteit Amsterdam, Amsterdam 1081HV, The Netherlands
- Centre for Analytical Sciences Amsterdam (CASA), Amsterdam 1098 XH, The Netherlands
- Naturalis Biodiversity Center, Leiden 2333 CR, The Netherlands
| | - Nicholas R. Casewell
- Centre for Snakebite Research and Interventions, Liverpool School of Tropical Medicine, Liverpool L3 5QA, UK
- Centre for Drugs and Diagnostics, Liverpool School of Tropical Medicine, Liverpool L3 5QA, 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, Amsterdam 1081HV, The Netherlands
- Centre for Analytical Sciences Amsterdam (CASA), Amsterdam 1098 XH, The Netherlands
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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: 34] [Impact Index Per Article: 8.5] [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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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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Successful Management of Two Patients with Intracranial Hemorrhage due to Carpet Viper (Echis ocellatus) Envenomation in a Limited-Resource Environment. Wilderness Environ Med 2019; 30:295-301. [PMID: 31229367 DOI: 10.1016/j.wem.2019.04.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2018] [Revised: 04/08/2019] [Accepted: 04/16/2019] [Indexed: 11/20/2022]
Abstract
The West African carpet viper (Echis ocellatus) causes more deaths than any other snake in sub-Saharan Africa. Carpet viper envenomations are characterized by a venom-induced consumption coagulopathy and systemic bleeding syndrome, in addition to local symptoms of painful progressive swelling and tissue destruction. The highest mortality rate is seen in the final stages of the syndrome, which typically ends with fatal internal bleeding or hemorrhagic shock. We present 2 cases of E ocellatus envenomation with intracranial hemorrhage seen at a rural hospital in Bembèrèkè, Benin, and describe the successful management of these patients in a limited-resource setting. In one case the patient was treated with an ineffective Indian-made antivenom before evaluation by the authors and continued to deteriorate until she was treated with effective antivenom 10 d after the bite. In both cases lumbar puncture was performed for diagnostic or therapeutic purposes with good effect, and both patients made full recoveries without sequelae. These cases demonstrate the remarkable ability of high-quality antivenoms to reverse life-threatening envenomations even in the final stages of the hemorrhagic syndrome and illustrate the dangers posed by low-quality antivenoms that have flooded the market in the developing world.
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Monzavi SM, Afshari R, Khoshdel AR, Mahmoudi M, Salarian AA, Samieimanesh F, Shirmast E, Mihandoust A. Analysis of effectiveness of Iranian snake antivenom on Viper venom induced effects including analysis of immunologic biomarkers in the Echis carinatus sochureki envenomed victims. Toxicon 2019; 158:38-46. [PMID: 30452924 DOI: 10.1016/j.toxicon.2018.11.293] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2018] [Revised: 11/09/2018] [Accepted: 11/11/2018] [Indexed: 02/08/2023]
Abstract
Snakebite is an important toxicologic emergency with the potential of triggering local and systemic inflammation. Antivenom has remained the mainstay of treatment for snakebite envenomation. In this study we sought to investigate the effectiveness of Iranian antivenom in a series of 44 viper envenomed patients through analysis of changes in clinical severity and the levels of inflammatory markers. Clinical envenomation severity assessed by snakebite severity score (SSS) and laboratory exams of the patients were recorded before (baseline visit) and after antivenom therapy. During 12-h antivenom therapy, the median (range) score of SSS significantly decreased from 3.5 (2-10) on admission to 1 (0-5) in the last visit (P < 0.001). Moreover, a significant decrease in prothrombin time and international normalized ratio was found (P = 0.006 and 0.008; respectively). Plasma concentrations of interleukin (IL) 1-β, IL-6, IL-8, tumor necrosis factor α (TNF-α), complement hemolytic activity (CH50) were also measured in 10 severely Echis carinatus sochureki envenomed victims and 10 age and gender-matched healthy controls. Except IL-8, the baseline levels of IL-1β, IL-6 and TNF-α in victims were significantly higher than healthy controls (P = 0.005, <0.001 and < 0.001, respectively). Moreover, the baseline level of CH50 was significantly lower in the patients compared to healthy controls (P < 0.001). After 12-h antivenom therapy, the plasma levels of IL-1β, IL-6 and TNF-α significantly decreased (P = 0.032, 0.006 and 0.003, respectively), the levels of IL-8 remained relatively unchanged and the CH50 significantly increased (P = 0.011). Iranian snake antivenom was effective in treating viper bite envenomation as it reversed clinical venom effects and restored near normal underlying inflammatory status. This study is the first to ascertain and report the effectiveness of this antivenom in human subjects.
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Affiliation(s)
- Seyed Mostafa Monzavi
- Medical Toxicology Center, Imam Reza Hospital, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Reza Afshari
- Medical Toxicology Center, Imam Reza Hospital, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Ali Reza Khoshdel
- Department of Epidemiology, School of Medicine, AJA University of Medical Sciences, Tehran, Iran
| | - Mahmoud Mahmoudi
- Immunology Research Center, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran; Central Laboratory, Imam Reza Hospital, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran.
| | | | - Farhad Samieimanesh
- Central Laboratory, Imam Reza Hospital, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Elham Shirmast
- Central Laboratory, Imam Reza Hospital, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Azam Mihandoust
- Medical Toxicology Center, Imam Reza Hospital, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
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Halilu S, Iliyasu G, Hamza M, Chippaux JP, Kuznik A, Habib AG. Snakebite burden in Sub-Saharan Africa: estimates from 41 countries. Toxicon 2018; 159:1-4. [PMID: 30594637 DOI: 10.1016/j.toxicon.2018.12.002] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2018] [Accepted: 12/21/2018] [Indexed: 11/20/2022]
Abstract
There is no reliable estimate of burden of snakebite-envenoming (SBE) in Sub-Saharan Africa (SSA). We derived from a meta-analysis the burden of SBE related deaths, amputations and Post-Traumatic Stress Disorder (PTSD) in 41 countries in SSA. The annual burden was estimated at 1.03 million DALYs (95% Confidence Interval: 0.80-1.28 million DALYs). This is similar to or higher than the burden of many Neglected Tropical Diseases (NTDs) and the finding advocates for a commensurate resources allocation towards control of SBE.
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Affiliation(s)
- Sadiq Halilu
- Infectious & Tropical Diseases Unit, Aminu Kano Teaching Hospital, Bayero University, Kano, Nigeria
| | - Garba Iliyasu
- Infectious & Tropical Diseases Unit, Aminu Kano Teaching Hospital, Bayero University, Kano, Nigeria
| | - Muhammad Hamza
- Infectious & Tropical Diseases Unit, Aminu Kano Teaching Hospital, Bayero University, Kano, Nigeria
| | | | | | - Abdulrazaq G Habib
- Infectious & Tropical Diseases Unit, Aminu Kano Teaching Hospital, Bayero University, Kano, Nigeria.
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26
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The snakebite problem and antivenom crisis from a health-economic perspective. Toxicon 2018; 150:115-123. [PMID: 29782952 DOI: 10.1016/j.toxicon.2018.05.009] [Citation(s) in RCA: 69] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2018] [Revised: 05/08/2018] [Accepted: 05/14/2018] [Indexed: 11/22/2022]
Abstract
The scourge of snakebite has been well documented but largely ignored by the global health community for several decades, especially the role that economics has played in causing and exacerbating this crisis. Every year millions of people in low and middle-income countries face death, disability and disadvantage from snakebite envenoming (SBE) without access to appropriate treatment. Health-economic factors pervade every aspect of this neglected problem. A multitude of financial and commercial factors helped to cause, and now perpetuate, shortages of high quality, affordable and region-appropriate antivenom in areas where they are most needed. Alongside the death, physical disability and psychological anguish from SBE is a debilitating financial toll, which includes both direct costs of treatment and indirect costs from lost income. SBE is a problem that disproportionately affects poor, rural and agrarian communities, with most victims being young and industrious subsistence workers. The burden of envenoming is often felt by families and communities that can least afford it, and negatively impacts local and national productivity. The lack of long-term investment in health systems to properly manage SBE has led to insufficient funding for antivenom development, procurement, quality control and distribution, despite highly favourable cost effectiveness of some antivenoms. This has contributed to market failures that have seen antivenom output fall and become inaccessible to most victims. Solutions to these problems exist and are achievable, however the challenge for advocates is to appreciate the importance of health-economics and ensure that strategies to redress the economic causes and consequences of SBE are themselves cost-effective and financially sustainable.
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Abstract
Snakebite envenoming is a neglected tropical disease that kills >100,000 people and maims >400,000 people every year. Impoverished populations living in the rural tropics are particularly vulnerable; snakebite envenoming perpetuates the cycle of poverty. Snake venoms are complex mixtures of proteins that exert a wide range of toxic actions. The high variability in snake venom composition is responsible for the various clinical manifestations in envenomings, ranging from local tissue damage to potentially life-threatening systemic effects. Intravenous administration of antivenom is the only specific treatment to counteract envenoming. Analgesics, ventilator support, fluid therapy, haemodialysis and antibiotic therapy are also used. Novel therapeutic alternatives based on recombinant antibody technologies and new toxin inhibitors are being explored. Confronting snakebite envenoming at a global level demands the implementation of an integrated intervention strategy involving the WHO, the research community, antivenom manufacturers, regulatory agencies, national and regional health authorities, professional health organizations, international funding agencies, advocacy groups and civil society institutions.
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Affiliation(s)
- José María Gutiérrez
- Instituto Clodomiro Picado, Facultad de Microbiología, Universidad de Costa Rica, PO Box 11501-2060, San José, Costa Rica
| | - Juan J Calvete
- Instituto de Biomedicina de Valencia, Consejo Superior de Investigaciones Científicas (CSIC), Valencia, Spain
| | | | - Robert A Harrison
- Alistair Reid Venom Research Unit, Liverpool School of Tropical Medicine, Liverpool, UK
| | - David J Williams
- Charles Campbell Toxinology Centre, School of Medicine &Health Sciences, University of Papua New Guinea, Boroko, National Capital District, Papua New Guinea
- Australian Venom Research Unit, Department of Pharmacology and Therapeutics, University of Melbourne, Parkville, Victoria, Australia
| | - David A Warrell
- Nuffield Department of Clinical Medicine, John Radcliffe Hospital, University of Oxford, Oxford, UK
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28
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Rogalski A, Soerensen C, Op den Brouw B, Lister C, Dashevsky D, Arbuckle K, Gloria A, Zdenek CN, Casewell NR, Gutiérrez JM, Wüster W, Ali SA, Masci P, Rowley P, Frank N, Fry BG. Differential procoagulant effects of saw-scaled viper (Serpentes: Viperidae: Echis) snake venoms on human plasma and the narrow taxonomic ranges of antivenom efficacies. Toxicol Lett 2017; 280:159-170. [PMID: 28847519 DOI: 10.1016/j.toxlet.2017.08.020] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Revised: 08/21/2017] [Accepted: 08/21/2017] [Indexed: 10/19/2022]
Abstract
Saw-scaled vipers (genus Echis) are one of the leading causes of snakebite morbidity and mortality in parts of Sub-Saharan Africa, the Middle East, and vast regions of Asia, constituting a public health burden exceeding that of almost any other snake genus globally. Venom-induced consumption coagulopathy, owing to the action of potent procoagulant toxins, is one of the most relevant clinical manifestations of envenomings by Echis spp. Clinical experience and prior studies examining a limited range of venoms and restricted antivenoms have demonstrated for some antivenoms an extreme lack of antivenom cross-reactivity between different species of this genus, sometimes resulting in catastrophic treatment failure. This study undertook the most comprehensive testing of Echis venom effects upon the coagulation of human plasma, and also the broadest examination of antivenom potency and cross-reactivity, to-date. 10 Echis species/populations and four antivenoms (two African, two Asian) were studied. The results indicate that the venoms are, in general, potently procoagulant but that the relative dependence on calcium or phospholipid cofactors is highly variable. Additionally, three out of the four antivenoms tested demonstrated only a very narrow taxonomic range of effectiveness in preventing coagulopathy, with only the SAIMR antivenom displaying significant levels of cross-reactivity. These results were in conflict with previous studies using prolonged preincubation of antivenom with venom to suggest effective cross-reactivity levels for the ICP Echi-Tab antivenom. These findings both inform upon potential clinical effects of envenomation in humans and highlight the extreme limitations of available treatment. It is hoped that this will spur efforts into the development of antivenoms with more comprehensive coverage for bites not only from wild snakes but also from specimens widely kept in zoological collections.
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Affiliation(s)
- Aymeric Rogalski
- Venom Evolution Lab, School of Biological Sciences, University of Queensland, St Lucia QLD 4072 Australia
| | - Christoffer Soerensen
- Venom Evolution Lab, School of Biological Sciences, University of Queensland, St Lucia QLD 4072 Australia
| | - Bianca Op den Brouw
- Venom Evolution Lab, School of Biological Sciences, University of Queensland, St Lucia QLD 4072 Australia
| | - Callum Lister
- Venom Evolution Lab, School of Biological Sciences, University of Queensland, St Lucia QLD 4072 Australia
| | - Daniel Dashevsky
- Venom Evolution Lab, School of Biological Sciences, University of Queensland, St Lucia QLD 4072 Australia
| | - Kevin Arbuckle
- Department of Biosciences, College of Science, Swansea University, Swansea SA2 8PP, UK
| | - Alexandra Gloria
- Venom Evolution Lab, School of Biological Sciences, University of Queensland, St Lucia QLD 4072 Australia
| | - Christina N Zdenek
- Venom Evolution Lab, School of Biological Sciences, University of Queensland, St Lucia QLD 4072 Australia
| | - Nicholas R Casewell
- Alistair Reid Venom Research Unit, Parasitology Department, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK
| | - José María Gutiérrez
- Instituto Clodomiro Picado, Facultad de Microbiología, Universidad de Costa Rica, San José, Costa Rica
| | - Wolfgang Wüster
- Molecular Ecology and Fisheries Genetics Laboratory (MEFGL), School of Biological Sciences, Bangor University, Bangor LL57 2UW, UK
| | - Syed A Ali
- Venom Evolution Lab, School of Biological Sciences, University of Queensland, St Lucia QLD 4072 Australia; HEJ Research Institute of Chemistry, International Centre for Chemical and Biological Sciences (ICCBS), University of Karachi, Karachi 75270, Pakistan
| | - Paul Masci
- Princess Alexandra Hospital, Translational Research Institute, University of Queensland, St Lucia, QLD 4072, Australia
| | - Paul Rowley
- Alistair Reid Venom Research Unit, Parasitology Department, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK
| | | | - Bryan G Fry
- Venom Evolution Lab, School of Biological Sciences, University of Queensland, St Lucia QLD 4072 Australia.
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Alekseeva A, Tretiakova D, Chernikov V, Utkin Y, Molotkovsky J, Vodovozova E, Boldyrev I. Heterodimeric V. nikolskii phospholipases A2 induce aggregation of the lipid bilayer. Toxicon 2017; 133:169-179. [DOI: 10.1016/j.toxicon.2017.05.015] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2017] [Revised: 05/12/2017] [Accepted: 05/15/2017] [Indexed: 11/16/2022]
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Abstract
This review of hematology in Africa highlights areas of current practice and the immediate needs for development and clinical research. Acute hematological practice is dominated by anemia, sickle cell disease, and the need to provide a safe and rapidly available supply of blood. There is a growing need for specialist services for bleeding and coagulation, hematological malignancy, and palliative care. There are many areas of practice where straightforward measures could yield large gains in patient care. There is an urgent need for good clinical research to describe the epidemiology, natural history, and management of hematological diseases in Africa.
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Affiliation(s)
- Julie Makani
- Department of Haematology and Blood Transfusion, Muhimbili University of Health and Allied Sciences, PO Box 65001, Dar-es-Salaam, Tanzania
| | - David J Roberts
- Radcliffe Department of Medicine, University of Oxford, National Health Service Blood and Transplant, John Radcliffe Hospital, Oxford OX3 9BQ, UK.
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Harrison RA, Gutiérrez JM. Priority Actions and Progress to Substantially and Sustainably Reduce the Mortality, Morbidity and Socioeconomic Burden of Tropical Snakebite. Toxins (Basel) 2016; 8:toxins8120351. [PMID: 27886134 PMCID: PMC5198546 DOI: 10.3390/toxins8120351] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2016] [Revised: 11/09/2016] [Accepted: 11/18/2016] [Indexed: 11/16/2022] Open
Abstract
The deliberations and conclusions of a Hinxton Retreat convened in September 2015, entitled “Mechanisms to reverse the public health neglect of snakebite victims” are reported. The participants recommended that the following priority actions be included in strategies to reduce the global impact of snake envenoming: (a) collection of accurate global snakebite incidence, mortality and morbidity data to underpin advocacy efforts and help design public health campaigns; (b) promotion of (i) public education prevention campaigns; (ii) transport systems to improve access to hospitals and (iii) establishment of regional antivenom-efficacy testing facilities to ensure antivenoms’ effectiveness and safety; (c) exploration of funding models for investment in the production of antivenoms to address deficiencies in some regions; (d) establishment of (i) programs for training in effective first aid, hospital management and post-treatment care of victims; (ii) a clinical network to generate treatment guidelines and (iii) a clinical trials system to improve the clinical management of snakebite; (e) development of (i) novel treatments of the systemic and local tissue-destructive effects of envenoming and (ii) affordable, simple, point-of-care snakebite diagnostic kits to improve the accuracy and rapidity of treatment; (f) devising and implementation of interventions to help the people and communities affected by physical and psychological sequelae of snakebite.
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Affiliation(s)
- Robert A Harrison
- Alistair Reid Venom Research Unit, Liverpool School of Tropical, Liverpool L35QA, UK.
| | - José María Gutiérrez
- Instituto Clodomiro Picado, Facultad de Microbiología, Universidad de Costa Rica, San José 11501-2060, Costa Rica.
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Hamza M, Idris MA, Maiyaki MB, Lamorde M, Chippaux JP, Warrell DA, Kuznik A, Habib AG. Cost-Effectiveness of Antivenoms for Snakebite Envenoming in 16 Countries in West Africa. PLoS Negl Trop Dis 2016; 10:e0004568. [PMID: 27027633 PMCID: PMC4814077 DOI: 10.1371/journal.pntd.0004568] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2015] [Accepted: 03/02/2016] [Indexed: 12/02/2022] Open
Abstract
Background Snakebite poisoning is a significant medical problem in agricultural societies in Sub Saharan Africa. Antivenom (AV) is the standard treatment, and we assessed the cost-effectiveness of making it available in 16 countries in West Africa. Methods We determined the cost-effectiveness of AV based on a decision-tree model from a public payer perspective. Specific AVs included in the model were Antivipmyn, FAV Afrique, EchiTab-G and EchiTab-Plus. We derived inputs from the literature which included: type of snakes causing bites (carpet viper (Echis species)/non-carpet viper), AV effectiveness against death, mortality without AV, probability of Early Adverse Reactions (EAR), likelihood of death from EAR, average age at envenomation in years, anticipated remaining life span and likelihood of amputation. Costs incurred by the victims include: costs of confirming and evaluating envenomation, AV acquisition, routine care, AV transportation logistics, hospital admission and related transportation costs, management of AV EAR compared to the alternative of free snakebite care with ineffective or no AV. Incremental Cost Effectiveness Ratios (ICERs) were assessed as the cost per death averted and the cost per Disability-Adjusted-Life-Years (DALY) averted. Probabilistic Sensitivity Analyses (PSA) using Monte Carlo simulations were used to obtain 95% Confidence Intervals of ICERs. Results The cost/death averted for the 16 countries of interest ranged from $1,997 in Guinea Bissau to $6,205 for Liberia and Sierra Leone. The cost/DALY averted ranged from $83 (95% Confidence Interval: $36-$240) for Benin Republic to $281 ($159–457) for Sierra-Leone. In all cases, the base-case cost/DALY averted estimate fell below the commonly accepted threshold of one time per capita GDP, suggesting that AV is highly cost-effective for the treatment of snakebite in all 16 WA countries. The findings were consistent even with variations of inputs in 1—way sensitivity analyses. In addition, the PSA showed that in the majority of iterations ranging from 97.3% in Liberia to 100% in Cameroun, Guinea Bissau, Mali, Nigeria and Senegal, our model results yielded an ICER that fell below the threshold of one time per capita GDP, thus, indicating a high degree of confidence in our results. Conclusions Therapy for SBE with AV in countries of WA is highly cost-effective at commonly accepted thresholds. Broadening access to effective AVs in rural communities in West Africa is a priority. Antivenom is the main intervention against snakebite poisoning but is relatively scarce, unaffordable and the situation has been compounded further by the recent cessation of production of effective antivenoms and marketing of inappropriate products. Given this crisis, we assessed the cost effectiveness of providing antivenoms in West Africa by comparing costs associated with antivenom treatment against their health benefits in decreasing mortality. In the most comprehensive analyses ever conducted, it was observed the incremental cost effectiveness ratio of providing antivenom ranged from $1,997 in Guinea Bissau to $6,205 for Liberia and Sierra-Leone per death averted while cost per Disability Adjusted Life Year (DALY) averted ranged from $83 for Benin Republic to $281 for Sierra-Leone. There is probability of 97.3–100% that antivenoms are very cost-effective in the analyses. These demonstrate antivenom is highly cost-effective and compares favorably to other commonly funded healthcare interventions. Providing and broadening antivenom access throughout areas at risk in rural West Africa should be prioritized given the considerable reduction in deaths and DALYs that could be derived at a relatively small cost.
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Affiliation(s)
- Muhammad Hamza
- College of Health of Sciences, Bayero University, Kano, Nigeria
| | - Maryam A. Idris
- College of Health of Sciences, Bayero University, Kano, Nigeria
| | - Musa B. Maiyaki
- College of Health of Sciences, Bayero University, Kano, Nigeria
| | - Mohammed Lamorde
- Infectious Diseases Institute, Makerere University College of Health Sciences, Kampala, Uganda
| | - Jean-Philippe Chippaux
- Institut de Recherche pour le Development, Cotonou, Benin Republic and Université Paris Descartes, Sorbonne Paris Cité, Faculté de Pharmacie, Paris, France
| | - David A. Warrell
- Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Andreas Kuznik
- College of Health of Sciences, Bayero University, Kano, Nigeria
- Infectious Diseases Institute, Makerere University College of Health Sciences, Kampala, Uganda
- Celgene Corporation, Warren, New Jersey, United States of America
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Sánchez A, Coto J, Segura Á, Vargas M, Solano G, Herrera M, Villalta M, Estrada R, Gutiérrez JM, León G. Effect of geographical variation of Echis ocellatus, Naja nigricollis and Bitis arietans venoms on their neutralization by homologous and heterologous antivenoms. Toxicon 2015; 108:80-3. [DOI: 10.1016/j.toxicon.2015.10.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2015] [Revised: 08/10/2015] [Accepted: 10/01/2015] [Indexed: 11/24/2022]
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Habib AG, Kuznik A, Hamza M, Abdullahi MI, Chedi BA, Chippaux JP, Warrell DA. Snakebite is Under Appreciated: Appraisal of Burden from West Africa. PLoS Negl Trop Dis 2015; 9:e0004088. [PMID: 26398046 PMCID: PMC4580425 DOI: 10.1371/journal.pntd.0004088] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2015] [Accepted: 08/28/2015] [Indexed: 01/16/2023] Open
Abstract
Background Snakebite envenoming (SBE) is a major problem in rural areas of West Africa (WA). Compared to other Neglected Tropical Diseases (NTD), the public health burden of SBE has not been well characterized. We estimated the impact of snakebite mortality and morbidity using the Disability Adjusted Life Years (DALYs) metrics for 16 countries in WA. Methods We used the reported annual number of SB deaths and mean age at time of SB and converted these into years of life lost (YLL). Similarly, the years of life lived with disability (YLD) were estimated by multiplying the number of amputations by the respective disability weight of 0.13. Results In WA, the annual cases of SB mortality and amputations ranged from 24 (95% Confidence Interval: 19–29) and 28 (17–48) respectively in Guinea-Bissau with the highest estimates of 1927 (1529–2333) and 2368 (1506–4043) respectively in Nigeria. We calculated that the annual DALYs associated with a SB death ranged from 1550 DALYs (95%CI: 1227–1873 DALYs) in Guinea Bissau to 124,484 DALYs (95%CI: 98,773–150,712 DALYs) in Nigeria. The annual DALYs associated with amputation for the two countries were 149 DALYs (95%CI: 91–256 DALYs) and 12,621 DALYs (95%CI: 8027–21,549 DALYs) respectively. The total burden of SBE was estimated at 319,874 DALYs (95% CI: 248,357–402,654 DALYs) in the 16 countries in WA. These estimates are similar, and in some instances even higher, than for other NTDs encountered in WA (e.g., Buruli ulcer, Echinococcosis, Intestinal Nematode Infections, Leishmaniasis, Onchocerchiasis, Trachoma and Trypanosomiasis) as reported in the Global Burden of Diseases 2010 (GBD). Conclusions The public health burden of SBE in WA is very substantial and similar to other more widely recognized NTDs. Efforts and funding commensurate with its burden should be made available for the control of snakebite in the sub-region. Snakebite envenoming (SBE) is a major problem in rural West Africa (WA). However, despite the high incidence of SBE in this region, government funding for the prevention or treatment of SBE is generally limited. In this analysis, we attempted to estimate how the public health burden of SBE compares to other more widely recognized Neglected Tropical Diseases (NTD). To this end, we estimated the impact of SBE mortality and morbidity based on the methodology outlined in the global burden of disease and reported our results in Disability Adjusted Life Years (DALYs) for 16 countries in WA. We calculated the total burden of SBE in WA at 320,000 DALYs (95% CI: 248,000–403,000 DALYs) per year with the least and highest burdens in Guinea-Bissau and Nigeria accounting for 0.5% and 43%, respectively. The vast majority of the public health burden (91%) is attributed to early mortality. We conclude that the public health burden of SBE in WA is substantial and similar to, and in some cases even exceeds, other more widely recognized NTDs such as Buruli ulcer, Echinococcosis, Intestinal Nematode Infections, Leishmaniasis, Onchocerchiasis, Trachoma and Trypanosomiasis. Efforts and funding commensurate with its public health burden should be made available for the control of snakebite.
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Affiliation(s)
| | - Andreas Kuznik
- College of Health of Sciences, Bayero University, Kano, Nigeria; Celgene Corporation, Warren, New Jersey, United States of America
| | - Muhammad Hamza
- College of Health of Sciences, Bayero University, Kano, Nigeria
| | | | - Basheer A Chedi
- College of Health of Sciences, Bayero University, Kano, Nigeria
| | - Jean-Philippe Chippaux
- Institut de Recherche pour le Développement, Cotonou, Benin Republic and Université Paris Descartes, Sorbonne Paris Cité, Faculté de Pharmacie, Paris, France
| | - David A Warrell
- Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
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Gutiérrez JM, Burnouf T, Harrison RA, Calvete JJ, Brown N, Jensen SD, Warrell DA, Williams DJ. A Call for Incorporating Social Research in the Global Struggle against Snakebite. PLoS Negl Trop Dis 2015; 9:e0003960. [PMID: 26379235 PMCID: PMC4574917 DOI: 10.1371/journal.pntd.0003960] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2015] [Accepted: 06/13/2015] [Indexed: 11/25/2022] Open
Affiliation(s)
- José María Gutiérrez
- Instituto Clodomiro Picado, Facultad de Microbiología, Universidad de Costa Rica, San José, Costa Rica
- * E-mail: (JMG); (TB)
| | - Thierry Burnouf
- Graduate Institute of Biomedical Materials and Tissue Engineering, Taipei Medical University, Taipei, Taiwan
- * E-mail: (JMG); (TB)
| | - Robert A. Harrison
- Alistair Reid Venom Research Unit, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Juan J. Calvete
- Instituto de Biomedicina de Valencia, Consejo Superior de Investigaciones Científicas (CSIC), Valencia, Spain
| | - Nicholas Brown
- Australian Venom Research Unit, Department of Pharmacology & Therapeutics, University of Melbourne, Parkville, Victoria, Australia
| | - Simon D. Jensen
- Australian Venom Research Unit, Department of Pharmacology & Therapeutics, University of Melbourne, Parkville, Victoria, Australia
- Charles Campbell Toxinology Centre, School of Medicine & Health Sciences, University of Papua New Guinea, Port Moresby, Papua New Guinea
| | - David A. Warrell
- Nuffield Department of Clinical Medicine, John Radcliffe Hospital, University of Oxford, Oxford, United Kingdom
| | - David J. Williams
- Australian Venom Research Unit, Department of Pharmacology & Therapeutics, University of Melbourne, Parkville, Victoria, Australia
- Charles Campbell Toxinology Centre, School of Medicine & Health Sciences, University of Papua New Guinea, Port Moresby, Papua New Guinea
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Habib AG, Lamorde M, Dalhat MM, Habib ZG, Kuznik A. Cost-effectiveness of antivenoms for snakebite envenoming in Nigeria. PLoS Negl Trop Dis 2015; 9:e3381. [PMID: 25569252 PMCID: PMC4287484 DOI: 10.1371/journal.pntd.0003381] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2014] [Accepted: 10/28/2014] [Indexed: 11/18/2022] Open
Abstract
Background Snakebite envenoming is a major public health problem throughout the rural tropics. Antivenom is effective in reducing mortality and remains the mainstay of therapy. This study aimed to determine the cost-effectiveness of using effective antivenoms for Snakebite envenoming in Nigeria. Methodology Economic analysis was conducted from a public healthcare system perspective. Estimates of model inputs were obtained from the literature. Incremental Cost Effectiveness Ratios (ICERs) were quantified as deaths and Disability-Adjusted-Life-Years (DALY) averted from antivenom therapy. A decision analytic model was developed and analyzed with the following model base-case parameter estimates: type of snakes causing bites, antivenom effectiveness to prevent death, untreated mortality, risk of Early Adverse Reactions (EAR), mortality risk from EAR, mean age at bite and remaining life expectancy, and disability risk (amputation). End-user costs applied included: costs of diagnosing and monitoring envenoming, antivenom drug cost, supportive care, shipping/freezing antivenom, transportation to-and-from hospital and feeding costs while on admission, management of antivenom EAR and free alternative snakebite care for ineffective antivenom. Principal Findings We calculated a cost/death averted of ($2330.16) and cost/DALY averted of $99.61 discounted and $56.88 undiscounted. Varying antivenom effectiveness through the 95% confidence interval from 55% to 86% yield a cost/DALY averted of $137.02 to $86.61 respectively. Similarly, varying the prevalence of envenoming caused by carpet viper from 0% to 96% yield a cost/DALY averted of $254.18 to $78.25 respectively. More effective antivenoms and carpet viper envenoming rather than non-carpet viper envenoming were associated with lower cost/DALY averted. Conclusions/Significance Treatment of snakebite envenoming in Nigeria is cost-effective with a cost/death averted of $2330.16 and cost/DALY averted of $99.61 discounted, lower than the country's gross domestic product per capita of $1555 (2013). Expanding access to effective antivenoms to larger segments of the Nigerian population should be a considered a priority. Snake bite is a major public health problem throughout rural communities in West Africa and leads to a significant number of deaths and disabilities per year. Even though effective antivenoms exist against the locally prevalent carpet viper and other poisonous snakes, they are generally not available in community settings, possibly because of their high acquisition cost. We evaluated the cost-effectiveness of making antivenom more broadly available in Nigeria by comparing the treatment costs associated with antivenom therapy against their medical benefit in reducing the risk of mortality. We find that the incremental cost effectiveness ratio (ICER) associated with making antivenom available in Nigeria was $2,330 per death averted and $100 per disability adjusted life year (DALY) averted. Both of these suggest that snakebite antivenom is highly cost-effective in Nigeria and they also compare very favorably against other commonly funded health interventions for which similar estimates exist. Since a substantial reduction in mortality and DALYs could be achieved at a relatively modest upfront cost, expanding access to antivenom to broader parts of the population should be a priority consideration for future investments in healthcare.
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Affiliation(s)
- Abdulrazaq G. Habib
- Infectious & Tropical Diseases Unit, College of Health Sciences, Bayero University Kano, Nigeria
- * E-mail:
| | - Mohammed Lamorde
- Infectious Diseases Institute, Makerere College of Health Sciences, Kampala, Uganda
| | - Mahmood M. Dalhat
- Infectious & Tropical Diseases Unit, College of Health Sciences, Bayero University Kano, Nigeria
| | - Zaiyad G. Habib
- Infectious & Tropical Diseases Unit, College of Health Sciences, Bayero University Kano, Nigeria
| | - Andreas Kuznik
- Infectious & Tropical Diseases Unit, College of Health Sciences, Bayero University Kano, Nigeria
- Infectious Diseases Institute, Makerere College of Health Sciences, Kampala, Uganda
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