Proceedings Chapter

Snake-byte: first national epidemiological study on snakebite shows high annual incidences in Nepal and Cameroon

ALCOBA, Gabriel, et al.

Abstract

Introduction: Snakebite envenoming affects 4.5-5.4 million people and kills 81,000-138,000 victims yearly according to the World Health Orga- nization (WHO), but estimates are extrapolations, and community-based country-wide studies are very scarce. Aim: To measure the impact of snakebite on human and animal health (incidence, mortality, disability) and livelihoods in Cameroon and Nepal. Methods: This epidemiological study is part of the SNAKE-BYTE project that aims at understanding the impact of snakebite in Cameroon and Nepal through one-health, health economy, and epidemiology using digital epidemiology and geo-health tools (Kobo-collect®, Stata® qGIS®, Guru-Maps®, AccesMod®). Based on minimal expected snakebite inci- dence of 100/100,000/year, 0.05% confidence limit, design effect of 2.0, 99% confidence level, 15% non-response margin, sample size was 61,000 people per country, i.e. 11,700 households in Cameroon and 13,800 in Nepal (respectively 5.2 and 4.4 persons per household). Households were preselected from satellite images, among 500 (2x250) randomly prese- lected administrative areas, where six mobile [...]

Reference

ALCOBA, Gabriel, et al. Snake-byte: first national epidemiological study on snakebite shows high annual incidences in Nepal and Cameroon. In: Abstracts from the 11th European Congress on Tropical Medicine and International Health. London : 2019. p. S67

DOI : 10.1093/trstmh/trz094

Available at: http://archive-ouverte.unige.ch/unige:125052

Disclaimer: layout of this document may differ from the published version.

1 / 1 Transactions of the Royal Societyof Tropical Medicine and Hygiene

4Dir. Policy, Planning, Budget, and Research, Ministry of Health, 5Internal medicine Dept., BP Koirala Institute of Health Sciences Juba, South Sudan; (BPKIHS), Dharan, Nepal; 5Dept. of Tropical Medicine and Public Health, Goethe University, 6Cameroon Society of Epidemiology (CaSE); Frankfurt, Germany; 7Centre International de Recherche, Enseignement, et Soins 6Division of Tropical and Humanitarian Medicine, Geneva University (CIRES); Hospitals, Geneva, Switzerland; The Snake-Byte consortium (François Chappuis, Nicolas Ray, San- 7Epicentre, Médecins Sans Frontières, , jib Kumar Sharma, Armand Nkwescheu, Franck Wanda, Gabriel Alcoba, Carlos Ochoa, Sara Babo Martins, Rafael Ruiz de Castañeda, Downloaded from https://academic.oup.com/trstmh/article-abstract/113/Supplement_1/S1/5569919 by guest on 19 October 2019 Introduction: Snakebite envenoming is the deadliest neglected tropi- Isabelle Bolon, Pratibha Bhetwal, Manish Subedi, Bhupendra Shah, cal disease globally, with 5 million cases and 81,000-138,000 yearly deaths. Agok Hospital, South Sudan, where Médecins Sans Frontières Anup Ghimire, Eric Comte, Ulrich Kuch) (MSF) supports the Ministry of Health, reported 341 snakebites in 2018. Introduction: Snakebite envenoming affects 4.5-5.4 million people and A new treatment algorithm was introduced in 2017, using two antiven- kills 81,000-138,000 victims yearly according to the World Health Orga- oms: Echitab-Plus for cytotoxic and haemotoxic envenoming (vipers, spit- nization (WHO), but estimates are extrapolations, and community-based ting cobras), and SAIMR-Polyvalent for neurotoxic envenoming (cobras, country-wide studies are very scarce. mambas). Aim: To measure the impact of snakebite on human and animal health Aim: To describe clinical symptoms, outcomes, and adverse reactions due (incidence, mortality, disability) and livelihoods in Cameroon and Nepal. to the antivenoms. Methods: This epidemiological study is part of the SNAKE-BYTE project Methods: We performed a prospective observational study of snakebite that aims at understanding the impact of snakebite in Cameroon and patients, with clinical evaluations at admission, 6h, 24h, hospital dis- Nepal through one-health, health economy, and epidemiology using charge, and 28d. Patients identified snakes using a photo album and digital epidemiology and geo-health tools (Kobo-collect®, Stata® qGIS®, bite wounds were swabbed for snake DNA. Ethical approval was given by Guru-Maps®, AccesMod®). Based on minimal expected snakebite inci- South Sudan and MSF ERBs. dence of 100/100,000/year, 0.05% confidence limit, design effect of 2.0, Results: We describe 151 patients admitted 14 March-August 2018, of 99% confidence level, 15% non-response margin, sample size was 61,000 whom 46 (31.3%) were <15 years and 84 (55.9%) were male; most were people per country, i.e. 11,700 households in Cameroon and 13,800 in students or farmers. Median travel time and distance to hospital was 2h Nepal (respectively 5.2 and 4.4 persons per household). Households were (IQR 1-3), and 5 km (IQR 1-50); 100 (86.2%) arrived <6h of being bitten. preselected from satellite images, among 500 (2x250) randomly prese- Most bites (82; 55.8%) occurred between 18h00-23h59, occurring most lected administrative areas, where six mobile survey teams conducted commonly at home (69; 47.3%). Patients identified puff adders (Bitis the e-questionnaires. After ethical approval by Cameroonian, Nepalese, arietans, 56.4%), spitting cobras (Naja nigricollis, 12.8%) and carpet vipers and Swiss authorities, surveys started in November 2018. (Echis pyramidum, 7.7%); PCR analysis is pending. Thirty-three (22.3%) Results: Interim data analysis on 5045 households in Cameroon and received traditional treatments. Patients requiring antivenom (56/146, 10,163 in Nepal, showed respectively 120 victims per 29,537 persons- 38.4%) presented with cytotoxic or cytotoxic-haemotoxic syndromes year and 141 victims per 46,888 persons-year. National snakebite inci- (including 25 bleeding, 15 with necrosis). Median extent of swelling was 9 dence rates per 100,000 persons-year translate to 406.3 (95%CI: 338.3, cm (IQR 5-35). Two patients had continued bleeding at 6h that resolved 484.0) or 65,008 victims in rural Cameroon (population 16 million), and at 24h. 20 minute-clotting test was abnormal in 5.2% (5/95). Patients 300.7 (95%CI: 254.1, 353.5) or 39,993 victims in Nepal’s Terai lowlands received 1-4 “treatments” of 3 vials; among the 84 Echitab-Plus treat- (population 13.3 million). Victims were young adults (median 30/31y), ments, no anaphylaxis or respiratory symptoms were described; 6.1% often farmers, predominantly males in Cameroon (54.5%) and females had itching/urticaria. 3 patients had probable/definite serum sickness at in Nepal (66.4%), and 22.5% were children <15y. Snakes were seen by 28d. No adverse events occurred after a single treatment of SAIMR. No victims in 66%-71.2% cases, indoors or outdoors. Snakebite case-fatality patient died. ratios were high: 5.8% (n=7/120) in Cameroon, and 6.6% (n=9/141) in Conclusion: This group of patients is younger than others described in Nepal. About 10% received some injections, likely antivenom. Only 46.0% sub-Saharan Africa. Mortality was zero, likely due improved access to care and 50.4% were taken to medical facilities. Multivariate analysis will and antivenoms. Unfortunately, pan-African polyvalent antivenoms are model “hotspots” including demographic, clinical, ecological and socio- not yet available nor affordable in most places in Africa, contributing to economic variables, and animals lost. snakebite’s high burden. MSF welcomes WHO’s Snakebite Roadmap. Conclusion: This first country-wide community-based study shows very high annual snakebite incidence and mortality in rural Cameroon and Nepal. It should help health authorities to estimate antivenom needs by 167 geographical area. SNAKE-BYTE: FIRST NATIONAL EPIDEMIOLOGICAL STUDY ON SNAKEBITE SHOWS HIGH ANNUAL INCIDENCES IN NEPAL AND 168 CAMEROON FAILURE OF MEXICAN ANTIVENOM TO IMPROVE CORRECTION Alcoba G.1,2,3, Ochoa C.2,4, Sharma S.K.5, Nkwescheu A.S.6, 7 2 2 2 OF COAGULOPATHY IN CROTALINAE ENVENOMATIONS IN Wanda F. , Babo Martins S. , Ruiz de Castañeda R. , Bolon I. , Ray N.2,4, Chappuis F.1,2 , the Snake-Byte consortium∗ 1Division of Tropical and Humanitarian Medicine, Geneva University Heckmann X.1, Lambert V.2, Mion G.3, Marty C.4, Perotti F.5, Hospitals (HUG); Carod J.F.6, Jolivet A.7, Boels D.8, Lehida Andi I.9, Larréché S.10 2Institute of Global Health, Faculty of Medicine, University of 1Emergency Dept., Western Guiana Hospital; Geneva (UNIGE); 2Dept. of Obstetrics and Gynaecology, Western Guiana Hospital, 3Medical Dept., Médecins sans Frontières; Saint-Laurent-du-Maroni, French Guiana; 4Institute for Environmental Sciences, University of Geneva 3Dept. of Anaesthesiology, Cochin Hospital, Paris, France; (UNIGE), Geneva, Switzerland; 4French Red Cross, Cayenne, French Guiana;

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