Knowledge of health workers on snakes and snakebite management and treatment seeking behavior of snakebite victims in Bhutan

BackgroundPublished information on snakebite is rare in Bhutan although remarkably higher number of snakebites and associated deaths are reported from other South Asian countries.Aims and methodologyStructured questionnaire was used to collect knowledge of health workers in snakebite management and health seeking behavior of snakebite victims as observed by health workers. Study was conducted in purposively sampled 10 Dzongkhags (district level administrative units) with higher incidence of snakebites.ResultHeath workers scored 27–91% (with an average of 63%, SD = 14) for 52 questions related to snake identification and snakebite management. Among 118 health workers interviewed, 23% had adequate knowledge on snakes and snakebite management while 77% had inadequate knowledge. Among 32 Doctors, 63% of them scored above or equal to 75%. Health workers from Sarpang scored higher (76%, SD = 11) than those from other Dzongkhags. Snakebite victim''s visit to local (traditional) healers prior to seeking medical help from hospital was observed by 75 (63%) health workers. Fifty one percent of health workers observed patients treated with local methods such as the use of black stone called Jhhar Mauro (believed to absorb snake venom), application of honey, rubbing of green herbal paste made up of Khenpa Shing (Artemisia myriantha Wallich ex Besser var. paleocephala [Pamp] Ling) and consumption of fluid made up of Neem leaf (Azadirachta indica Juss). Use of tight tourniquet as a first aid to snakebite was observed by 80% of the health workers.ConclusionHealth workers lack confidence in snakebite management. Snakebite victims are likely to suffer from harmful local practices and traditional beliefs on local treatment practices. Empowering health workers with adequate knowledge on snakebite management and making locals aware in pre-hospital care of snakebites are needed to improve the pre- and in-hospital management of snakebite in Bhutan.     

What the snake leaves in its wake: Functional limitations and disabilities among snakebite victims in Ghanaian communities

BackgroundThe estimated five million snakebites per year are an important health problem that mainly affect rural poor populations. The global goal is to halve both mortality and morbidity from this neglected tropical disease by 2030. Data on snakebite morbidity are sparse and mainly obtained from hospital records.MethodsThis community-based study was conducted among 379 rural residents with or without a history of snakebite in the Ashanti and Upper West regions of Ghana. All participants in the snakebite group were bitten at least six months before the day of survey. The World Health Organisation Disability Assessment Schedule 2.0 (WHODAS 2.0) and the Buruli Ulcer Functional Limitation Score were used to obtain patient-reported measure of functioning and disability. Long-term consequences were evaluated based on the severity of the symptoms at the time of the snakebite.FindingsThe median (IQR) time since the snakebite was 8.0 (3.5–16.5) years. The relative risk of disability was 1.54 (95% CI, 1.17–2.03) in the snakebite group compared to the community controls. Among patients with clinical symptoms suggesting envenoming at the time of bite, 35% had mild/moderate disabilities compared to 20% in the control group. The disability domains mainly affected by snakebite envenoming were cognition level, mobility, life activities and participation in society. A combination of the severity of symptoms at the time of the bite, age, gender and region of residence most accurately predicted the odds of having functional limitations and disabilities.ConclusionThe burden of snakebite in the community includes long-term disabilities of mild to moderate severity, which need to be considered when designing appropriate public health interventions. Estimating the total burden of snakebite is complicated by geographic differences in types of snakes and their clinical manifestations.     

Evaluating spatiotemporal dynamics of snakebite in Sri Lanka: Monthly incidence mapping from a national representative survey sample

BackgroundSnakebite incidence shows both spatial and temporal variation. However, no study has evaluated spatiotemporal patterns of snakebites across a country or region in detail. We used a nationally representative population sample to evaluate spatiotemporal patterns of snakebite in Sri Lanka.MethodologyWe conducted a community-based cross-sectional survey representing all nine provinces of Sri Lanka. We interviewed 165 665 people (0.8% of the national population), and snakebite events reported by the respondents were recorded. Sri Lanka is an agricultural country; its central, southern and western parts receive rain mainly from Southwest monsoon (May to September) and northern and eastern parts receive rain mainly from Northeast monsoon (November to February). We developed spatiotemporal models using multivariate Poisson process modelling to explain monthly snakebite and envenoming incidences in the country. These models were developed at the provincial level to explain local spatiotemporal patterns.Principal findingsSnakebites and envenomings showed clear spatiotemporal patterns. Snakebite hotspots were found in North-Central, North-West, South-West and Eastern Sri Lanka. They exhibited biannual seasonal patterns except in South-Western inlands, which showed triannual seasonality. Envenoming hotspots were confined to North-Central, East and South-West parts of the country. Hotspots in North-Central regions showed triannual seasonal patterns and South-West regions had annual patterns. Hotspots remained persistent throughout the year in Eastern regions. The overall monthly snakebite and envenoming incidences in Sri Lanka were 39 (95%CI: 38–40) and 19 (95%CI: 13–30) per 100 000, respectively, translating into 110 000 (95%CI: 107 500–112 500) snakebites and 45 000 (95%CI: 32 000–73 000) envenomings in a calendar year.Conclusions/significanceThis study provides information on community-based monthly incidence of snakebites and envenomings over the whole country. Thus, it provides useful insights into healthcare decision-making, such as, prioritizing locations to establish specialized centres for snakebite management and allocating resources based on risk assessments which take into account both location and season.     

“Then they prayed,they did nothing else,they just prayed for the boy and he was well”: A qualitative investigation into the perceptions and behaviours surrounding snakebite and its management in rural communities of Kitui county,Kenya

IntroductionHuman-snake interactions are common in tropical regions where subsistence-farming and livestock-herding activities predominate alongside proliferation of snakes. Local beliefs and perceptions about snakes and snakebites influence human behaviour. Understanding these beliefs and perceptions can inform the development of resources to drive behaviour change and to minimise the risk of injury to both humans and snakes. This qualitative study, conducted between May and July 2019, sought to explore the beliefs and perceptions regarding snakes and snakebites, and methods of prevention and management among members of the community in Kitui County, Kenya.MethodsSemi-structured interviews were used to collect qualitative data from 23 participants, recruited using a stratified purposeful sampling strategy in four selected sub-counties of Kitui county. Interview data was anonymised and coded and a thematic analysis was conducted using NVivo 12.ResultsPeople from Kitui county mostly had negative perceptions about snakes. There was a generalised awareness of the need to prevent snakebite, predominantly through keeping snakes away from homes/compounds. However, implementation was limited by financial constraints. Participants also identified logistic and financial obstacles to early hospital presentation following a snakebite, and they expressed a strong preference of having their snakebites treated in a hospital over consulting traditional healers. There was a universal recognition of the benefit of early intervention with a specific appreciation of the utility of the black stone. Furthermore, the removal of a snake’s “teeth” was an expected treatment outcome for some community members, with the failure to do so perceived as causing poor wound healing or persistence of symptoms. Some religious groups held views which differed from most participants.ConclusionThere is a need to explore and clarify common misconceptions about snakes and first aid treatment of snakebites, encourage learning about the true nature of snakes, and highlight beneficial uses of snakes. A change in the epistemological conception of community education material by enhancing the value and use of local forms of knowledge, and the employment of art techniques to transmit this knowledge, could improve community perception and methods of snakebite prevention. Patient expectations should be appropriately managed by discussing possible outcomes, incorporating follow-up visits and addressing long-term complications of snakebites.     

Snakebites in Two Rural Districts in Lao PDR: Community-Based Surveys Disclose High Incidence of an Invisible Public Health Problem

BackgroundThe Lao PDR (Laos) is one of the least developed countries in Asia with an estimated 25% of the population living in poverty. It is the habitat of some highly venomous snakes and the majority of the population earns their living from agricultural activities. Under these circumstances the incidence of snakebites is expected to be high.MethodsTwo cross-sectional, community-based surveys were performed in Champone and Phin district, Savannakhet province, Lao PDR to estimate snakebite incidence. Multistage random sampling was used. In the first stage approximately 40% of all villages in each district were randomly selected. In the second stage 33% of all households in each village were randomly chosen. Members of the selected households were interviewed about snakebites during the previous 12 months.ResultsThirty-five of 9856 interviewees reported a snakebite in a 12 month period in Champone district and 79 of 7150 interviewees in Phin district. The estimated incidence is 355 snakebites per 100,000 persons per year and 1105 per 100,000 in Champone and Phin district respectively. All snakebite victims received treatment by traditional healers or self-treatment at home and nobody went to a hospital. Incidence of snakebites, calculated on the basis of hospital records of 14 district hospitals and Savannakhet provincial hospital, ranged from 3 to 14 cases per 100,000 persons per year between 2012 and 2014.ConclusionIncidence of snakebites is high in rural communities in Laos with significant regional differences. Poverty most likely contributes significantly to the higher number of snakebites in Phin district. Hospital statistics profoundly underestimates snakebite incidence, because the majority of snakebite victims receive only treatment by traditional healers or self-treatment in their village. There is an urgent need to train medical staff and students in management of snakebite patients and make snake antivenom available to cope effectively with this important public health problem in order to prevent fatalities and disabilities.     

Health and economic burden estimates of snakebite management upon health facilities in three regions of southern Burkina Faso

BackgroundSnakebite has become better recognized as a significant cause of death and disability in Sub-Saharan Africa, but the health economic consequences to victims and health infrastructures serving them remain poorly understood. This information gap is important as it provides an evidence-base guiding national and international health policy decision making on the most cost-effective interventions to better manage snakebite. Here, we assessed hospital-based data to estimate the health economic burden of snakebite in three regions of Burkina Faso (Centre-Ouest, Hauts Bassins and Sud-Ouest).MethodologyPrimary data of snakebite victims admitted to regional and district health facilities (eg, number of admissions, mortality, hospital bed days occupied) was collected in three regions over 17 months in 2013/14. The health burden of snakebite was assessed using Disability-Adjusted Life Years (DALYs) calculations based upon hospitalisation, mortality and disability data from admitted patients amongst other inputs from secondary sources (eg, populations, life-expectancy and age-weighting constants). An activity-based costing approach to determine the direct cost of snake envenoming included unit costs of clinical staff wages, antivenom, supportive care and equipment extracted from context-relevant literature.FindingsThe 10,165 snakebite victims admitted to hospital occupied 28,164 hospital bed days over 17 months. The annual rate of hospitalisation and mortality of admitted snakebite victims was 173 and 1.39/100,000 population, respectively. The estimated annual (i) DALYs lost was 2,153 (0.52/1,000) and (ii) cost to hospitals was USD 506,413 (USD 49/hospitalisation) in these three regions of Burkina Faso. These costs appeared to be influenced by the number of patients receiving antivenom (10.90% in total) in each area (highest in Sud-Ouest) and the type of health facility.ConclusionThe economic burden of snake envenoming is primarily shouldered by the rural health centres closest to snakebite victims–facilities that are typically least well equipped or resourced to manage this burden. Our study highlights the need for more research in other regions/countries to demonstrate the burden of snakebite and the socioeconomic benefits of its management. This evidence can guide the most cost-effective intervention from government and development partners to meet the snakebite-management needs of rural communities and their health centres.     

Mapping snakebite epidemiology in Nicaragua--pitfalls and possible solutions

Background

Snakebites are a public health problem in Nicaragua: it is a tropical developing country, venomous snakes are present and there are reports of snakebites treated both in the formal and informal health care system. We aimed to produce an incidence map using data reported by the health care system that would be used to allocate resources. However, this map may suffer from case detection bias and decisions based on this map will neglect snakebite victims who do not receive healthcare. To avoid this error, we try to identify where underreporting is likely based on available information.

Method and Findings

The Nicaraguan municipalities are categorized by precipitation, altitude and geographical location into regions of assumed homogenous snake prevalence. Socio-economic and healthcare variables hypothesized to be related to underreporting of snakebites are aggregated into an index. The environmental region variable, the underreporting index and three demographic variables (rurality, sex and age distribution) are entered in a Poisson regression model of municipality-level snakebite incidence. In this model, the underreporting index is non-linearly associated with snakebite incidence, a finding we attribute to underreporting in the most deprived municipalities. The municipalities with the worst scoring on the underreporting index and those with combined low reported incidence and large rural population are identified as likely underreporting. 3,286 snakebite cases were reported in 2005–2009, corresponding to a 5-year incidence of 56 bites per 100,000 inhabitants (municipality range: 0–600 cases per 100,000 inhabitants).

Conclusions

Using publicly available data, we identified areas likely to be underreporting snakebites and highlighted these areas instead of leaving them “white” on the incidence map. The effects of the case detection bias on the distribution of resources against snakebites could decrease. Although not yet verified empirically, our study provides an example of how snake bite epidemiology may be investigated in similar settings worldwide at a low cost.     

A painful journey to antivenom: The therapeutic itinerary of snakebite patients in the Brazilian Amazon (The QUALISnake Study)

Access to antivenoms is not guarranteed for vulnerable populations that inhabit remote areas in the Amazon. The study of therapeutic itineraries (TI) for treatment of snakebites would support strategies to provide timely access to users. A TI is the set of processes by which individuals adhere to certain forms of treatment, and includes the path traveled in the search for healthcare, and practices to solve their health problems. This study aims to describe TIs of snakebite patients in the Brazilian Amazon. This study was carried out at the Fundação de Medicina Tropical Doutor Heitor Vieira Dourado, in Manaus, state of Amazonas, Brazil. The itinerary from the moment of the bite to the patient’s admission to the reference unit was analyzed. Sample size was defined by saturation. After an exploratory survey to collect epidemiological variables, in-depth interviews were conducted following a semi-structured guide. Patients originated from rural areas of 11 different municipalities, including ones located >500 kilometers from Manaus. A great fragmentation was observed in the itineraries, marked by several changes of means of transport along the route. Four themes emerged from the analysis: exposure to snakebite during day-to-day activities, use of traditional therapeutic practices, and personal perception of the severity, as well as the route taken and its contingencies. Access to healthcare requires considerable effort on the part of snakebite patients. Major barriers were identified, such as the low number of hospitals that offer antivenom treatment, poor access to healthcare due to long distances and geographic barriers, low acceptability of healthcare offered in countryside, lack of use of personal protective equipment, common use of ineffective or deleterious self-care practices, late recognition of serious clinical signs and resistance to seeking medical assistance. Health education, promotion of immediate transport to health centers and decentralization of antivenom from reference hospitals to community healthcare centers in the Brazilian Amazon are more effective strategies that would to maximize access to antivenom treatment.     

Epidemiological study of snakebite cases in Sikkim: Risk modeling with regard to the habitat suitability of common venomous snakes

BackgroundSnakebite envenoming is listed as category ‘A’ Neglected Tropical Disease. To achieve the target of WHO (World Health Organization) 2019, it becomes necessary to understand various attributes associated with snakebite including community awareness, improvisation of medical facilities and to map the potential distribution of venomous snakes responsible for the bite. Hence this study is conducted in Sikkim, India to understand the epidemiology of snakebite in Sikkim. The potential distribution and risk mapping of five common venomous snakes are done for effective management of snakebite cases.Methods and findingsThe snakebite cases registered in six district hospitals and four PHCs (Primary Health Centers) of Sikkim were collected from the year 2011 to 2018. Community survey was also conducted to supplement the data. Ecological Niche Modeling (ENM) was performed to predict the potential habitat of five common venomous snakes of Sikkim. The risk modeling of snakebite cases was done at the level of Gram Panchayat Unit (GPU) using Geographically Weighted Regression (GWR) and Ordinary Linear Square (OLS) model. We found higher number of male victims inflicted with snakebite envenomation. The potential distribution of the five venomous snakes showed satisfactory mean AUC (Area under Curve) value. Both the models showed significant positive association of snakebite cases with habitat suitability of the venomous snakes. Hospital data revealed no death cases whereas community data reported 24 deaths.ConclusionsDeath from snakebite reflected in community data but not in hospital data strongly indicates the people’s belief in traditional medicine. Though people of Sikkim have rich traditional knowledge, in case of snakebite traditional practices may be ineffective leading to loss of life. Sensitizing people and improving medical facilities along with proper transport facilities in rural areas might significantly reduce the snakebite casualties in the state.     

Availability,affordability and stock-outs of commodities for the treatment of snakebite in Kenya

BackgroundAnnually, about 2.7 million snakebite envenomings occur globally. Alongside antivenom, patients usually require additional care to treat envenoming symptoms and antivenom side effects. Efforts are underway to improve snakebite care, but evidence from the ground to inform this is scarce. This study, therefore, investigated the availability, affordability, and stock-outs of antivenom and commodities for supportive snakebite care in health facilities across Kenya.Methodology/principal findingsThis study used an adaptation of the standardised World Health Organization (WHO)/Health Action International methodology. Data on commodity availability, prices and stock-outs were collected in July-August 2020 from public (n = 85), private (n = 36), and private not-for-profit (n = 12) facilities in Kenya. Stock-outs were measured retrospectively for a twelve-month period, enabling a comparison of a pre-COVID-19 period to stock-outs during COVID-19. Affordability was calculated using the wage of a lowest-paid government worker (LPGW) and the impoverishment approach. Accessibility was assessed combining the WHO availability target (≥80%) and LPGW affordability (<1 day’s wage) measures. Overall availability of snakebite commodities was low (43.0%). Antivenom was available at 44.7% of public- and 19.4% of private facilities. Stock-outs of any snakebite commodity were common in the public- (18.6%) and private (11.7%) sectors, and had worsened during COVID-19 (10.6% versus 17.0% public sector, 8.4% versus 11.7% private sector). Affordability was not an issue in the public sector, while in the private sector the median cost of one vial of antivenom was 14.4 days’ wage for an LPGW. Five commodities in the public sector and two in the private sector were deemed accessible.ConclusionsAccess to snakebite care is problematic in Kenya and seemed to have worsened during COVID-19. To improve access, efforts should focus on ensuring availability at both lower- and higher-level facilities, and improving the supply chain to reduce stock-outs. Including antivenom into Universal Health Coverage benefits packages would further facilitate accessibility.     

Treatment outcomes among snakebite patients in north-west Ethiopia—A retrospective analysis

BackgroundMillions of people are bitten by venomous snakes annually, causing high mortality and disability, but the true burden of this neglected health issue remains unknown. Since 2015, Médecins Sans Frontières has been treating snakebite patients in a field hospital in north-west Ethiopia. Due to the poor market situation for effective and safe antivenoms for Sub-Saharan Africa, preferred antivenom was not always available, forcing changes in choice of antivenom used. This study describes treatment outcomes and the effectiveness and safety of different antivenoms used.Methodology / Principal findingsThis retrospective observational study included 781 snakebite patients presenting at the field hospital between 2015 and 2019. Adjusted odds ratios, 95%-CI and p-values were used to compare the treatment outcome of patients treated with Fav-Afrique (n = 149), VacSera (n = 164), and EchiTAb-PLUS-ICP (n = 156) antivenom, and to identify the risk of adverse reactions for each antivenom. Whereas only incidental snakebite cases presented before 2015, after treatment was made available, cases rapidly increased to 1,431 in 2019. Envenomation was mainly attributed to North East African saw-scaled viper (Echis pyramidum) and puff adder (Bitis arietans). Patients treated with VacSera antivenom showed lower chance of uncomplicated treatment outcome (74.4%) compared to Fav-Afrique (93.2%) and EchiTAb-PLUS-ICP (90.4%). VacSera and EchiTAb-PLUS-ICP were associated with 16- and 6-fold adjusted odds of treatment reaction compared to Fav-Afrique, respectively, and VacSera was weakly associated with higher odds of death.Conclusions / SignificanceSnakebite frequency is grossly underreported unless treatment options are available. Although EchiTAb-PLUS-ICP showed favorable outcomes in this retrospective analysis, prospective randomized trials are needed to evaluate the effectiveness and safety of the most promising antivenoms for Sub-Saharan Africa. Structural investment in sustained production and supply of antivenom is urgently needed.     

Knowledge Levels and Training Needs of Disaster Medicine among Health Professionals,Medical Students,and Local Residents in Shanghai,China

Background

Disaster is a serious public health issue. Health professionals and community residents are main players in disaster responses but their knowledge levels of disaster medicine are not readily available. This study aimed to evaluate knowledge levels and training needs of disaster medicine among potential disaster responders and presented a necessity to popularize disaster medicine education.

Methods

A self-reporting questionnaire survey on knowledge level and training needs of disaster medicine was conducted in Shanghai, China, in 2012. A total of randomly selected 547 health professionals, 456 medical students, and 1,526 local residents provided intact information. The total response rate was 93.7%.

Results

Overall, 1.3% of these participants have received systematic disaster medicine training. News media (87.1%) was the most common channel to acquire disaster medicine knowledge. Although health professionals were more knowledgeable than community residents, their knowledge structure of disaster medicine was not intact. Medical teachers were more knowledgeable than medical practitioners and health administrators (p = 0.002). Clinicians performed better than public health physicians (p<0.001), whereas public health students performed better than clinical medical students (p<0.001). In community residents, education background significantly affected the knowledge level on disaster medicine (p<0.001). Training needs of disaster medicine were generally high among the surveyed. ‘Lecture’ and ‘practical training’ were preferred teaching methods. The selected key and interested contents on disaster medicine training were similar between health professionals and medical students, while the priorities chosen by local residents were quite different from health professionals and medical students (p<0.001).

Conclusions

Traditional clinical-oriented medical education might lead to a huge gap between the knowledge level on disaster medicine and the current needs of disaster preparedness. Continuing medical education and public education plans on disaster medicine via media should be practice-oriented, and selectively applied to different populations and take the knowledge levels and training needs into consideration.     

Novel transdisciplinary methodology for cross-sectional analysis of snakebite epidemiology at national scale

BackgroundWorldwide, it is estimated that snakes bite 4.5–5.4 million people annually, 2.7 million of which are envenomed, and 81,000–138,000 die. The World Health Organization reported these estimates and recognized the scarcity of large-scale, community-based, epidemiological data. In this context, we developed the “Snake-Byte” project that aims at (i) quantifying and mapping the impact of snakebite on human and animal health, and on livelihoods, (ii) developing predictive models for medical, ecological and economic indicators, and (iii) analyzing geographic accessibility to healthcare. This paper exclusively describes the methodology we developed to collect large-scale primary data on snakebite in humans and animals in two hyper-endemic countries, Cameroon and Nepal.Methodology/Principal findingsWe compared available methods on snakebite epidemiology and on multi-cluster survey development. Then, in line with those findings, we developed an original study methodology based on a multi-cluster random survey, enhanced by geospatial, One Health, and health economics components. Using a minimum hypothesized snakebite national incidence of 100/100,000/year and optimizing design effect, confidence level, and non-response margin, we calculated a sample of 61,000 people per country. This represented 11,700 households in Cameroon and 13,800 in Nepal. The random selection with probability proportional to size generated 250 clusters from all Cameroonian regions and all Nepalese Terai districts. Our household selection methodology combined spatial randomization and selection via high-resolution satellite images. After ethical approval in Switerland (CCER), Nepal (BPKIHS), and Cameroon (CNERSH), and informed written consent, our e-questionnaires included geolocated baseline demographic and socio-economic characteristics, snakebite clinical features and outcomes, healthcare expenditure, animal ownership, animal outcomes, snake identification, and service accessibility.Conclusions/SignificanceThis novel transdisciplinary survey methodology was subsequently used to collect countrywide snakebite envenoming data in Nepal and Cameroon. District-level incidence data should help health authorities to channel antivenom and healthcare allocation. This methodology, or parts thereof, could be easily adapted to other countries and to other Neglected Tropical Diseases.     

Knowledge of Lassa fever,its prevention and control practices and their predictors among healthcare workers during an outbreak in Northern Nigeria: A multi-centre cross-sectional assessment

BackgroundThe year 2020 Lassa fever (LF) outbreak had the greatest disease burden and this can place an enormous strain on the already overstretched healthcare system and can potentially increase morbidity and mortality due to infectious diseases.Therefore, having a knowledgeable healthcare workforce with appropriate skills and competencies to prevent and manage outbreaks of a neglected infectious disease such as LF in Nigeria will potentially enhance public health. Thus, this survey assessed the level of knowledge of LF and its prevention and control (PC) measures amongst the healthcare workers (HCWs) during a LF outbreak in Katsina state, Nigeria.Methodology/Principal findingsDuring this cross-sectional survey, HCWs complete a validated 29-item questionnaire comprising 18 items on the knowledge of LF and its PC measures and an item on global self-evaluation of their LF knowledge. Psychometric properties of the questionnaire were evaluated. Chi-square and binary logistic regression analyses were conducted.Out of 435 HCWs invited, a total of 400 participated in the study (92% response rate). The majority of participants (51.8%) demonstrated inadequate LF knowledge, with 62.9% of those scoring low having a high self-perception of their LF knowledge with the global scale. This LF knowledge over-estimation was predicted by LF training status (odds ratio (OR) 2.53; 95% CI: 1.49–4.30; p = 0.001). The level of LF knowledge and its PC measures among the study participants was low (11.60±8.14, 64.4%) and predicted by participants’ LF training status (OR 2.06; 95% CI: 1.19–3.57; p = 0.009), place of work (OR 1.82; 95% CI: 1.07–3.08; p = 0.03) and their designations (OR 2.40; 95% CI: 1.10–5.22; p = 0.03).ConclusionThe level of knowledge of LF and its PC measures among the HCWs surveyed was suboptimal and participants’ LF training status, place of work and occupational category were the significant predictors. In addition, LF knowledge overestimation on a global scale was observed among a majority of HCWs and this was also predicted by LF training status. Therefore, there is a critical need for health authorities in Nigeria to prioritize continuous on-the-job training of HCWs on priority neglected tropical diseases such as Lassa fever.     

Snakebites in “Invisible Populations”: A cross-sectional survey in riverine populations in the remote western Brazilian Amazon

In the Brazilian Amazon, long distances, low healthcare coverage, common use of ineffective or deleterious self-care practices, and resistance to seeking medical assistance have an impact on access to antivenom treatment. This study aimed to estimate snakebite underreporting, and analyze barriers that prevent victims from obtaining healthcare in communities located in 15 municipalities on the banks of the Solimões, Juruá and Purus Rivers, in the remote Western Brazilian Amazon. Information on the participants’ demographics, previous snakebites, access to healthcare, time taken to reach medical assistance, use of self-care practices, and the reason for not accessing healthcare were collected through semi-structured interviews. In the case of deaths, information was collected by interviewing parents, relatives or acquaintances. A total of 172 participants who reported having suffered snakebites during their lifetime were interviewed. A total of 73 different treatment procedures was reported by 65.1% of the participants. Participants living in different river basins share few self-care procedures that use traditional medicine, and 91 (52.9%) participants reported that they had access to healthcare. Living in communities along the Juruá River [OR = 12.6 (95% CI = 3.2–49.7; p<0.001)] and the use of traditional medicine [OR = 11.6 (95% CI = 3.4–39.8; p<0.001)] were variables that were independently associated to the lack of access to healthcare. The main reasons for not accessing healthcare were the pprioritization of traditional treatments (70.4%), and the failure to recognize the situation as being potentially severe (50.6%). Four deaths from complications arising from the snakebite were reported, and three of these were from communities on the banks of the Juruá River. Only one of these received medical assistance. We found an unexpectedly high underreporting of snakebite cases and associated deaths. Snakebite victims utilized three main different healing systems: 1) self-care using miscellaneous techniques; 2) official medical healthcare generally combined with traditional practices; and 3) self-care using traditional practices combined with Western medicines. To mitigate snakebite burden in the Brazilian Amazon, an innovative intervention that would optimize timely delivery of care, including antivenom distribution among existing community healthcare centers, is needed.     

The global burden of snakebite: a literature analysis and modelling based on regional estimates of envenoming and deaths

Background

Envenoming resulting from snakebites is an important public health problem in many tropical and subtropical countries. Few attempts have been made to quantify the burden, and recent estimates all suffer from the lack of an objective and reproducible methodology. In an attempt to provide an accurate, up-to-date estimate of the scale of the global problem, we developed a new method to estimate the disease burden due to snakebites.

Methods and Findings

The global estimates were based on regional estimates that were, in turn, derived from data available for countries within a defined region. Three main strategies were used to obtain primary data: electronic searching for publications on snakebite, extraction of relevant country-specific mortality data from databases maintained by United Nations organizations, and identification of grey literature by discussion with key informants. Countries were grouped into 21 distinct geographic regions that are as epidemiologically homogenous as possible, in line with the Global Burden of Disease 2005 study (Global Burden Project of the World Bank). Incidence rates for envenoming were extracted from publications and used to estimate the number of envenomings for individual countries; if no data were available for a particular country, the lowest incidence rate within a neighbouring country was used. Where death registration data were reliable, reported deaths from snakebite were used; in other countries, deaths were estimated on the basis of observed mortality rates and the at-risk population. We estimate that, globally, at least 421,000 envenomings and 20,000 deaths occur each year due to snakebite. These figures may be as high as 1,841,000 envenomings and 94,000 deaths. Based on the fact that envenoming occurs in about one in every four snakebites, between 1.2 million and 5.5 million snakebites could occur annually.

Conclusions

Snakebites cause considerable morbidity and mortality worldwide. The highest burden exists in South Asia, Southeast Asia, and sub-Saharan Africa.     

Protease inhibitors in serum and urine of snakebite victims

In victims of poisonous snakebites, serum total antichymotryptic activity but not the antitryptic activity was found to be increased. In addition, urinary antitryptic activity was found to be markedly elevated. In nonpoisonous snakebite cases, no such differences were noted. Ion-exchange chromatographic analysis of serum protease inhibitors revealed the absence of inhibitory activity in the alpha 2-macroglobulin fraction and elevation of alpha 1-antichymotrypsin in poisonous bite cases. In addition, there was a significant increase in the ratio of cationic to anionic fraction of alpha 1-protease inhibitor compared to normals. Urinary antitryptic activity could serve as a reliable index in assessing clinical improvement in snakebite victims during treatment and in differentiating poisonous from nonpoisonous cases.     

毒蛇咬伤患者院前早期程序化急救处理方案的应用观察

目的探讨毒蛇咬伤患者院前早期程序化急救处理方案的应用价值。方法回顾性分析我院58例毒蛇咬伤患者应用院前早期程序化急救处理方案的临床资料。结果 58例毒蛇咬伤患者经院前早期程序化急救处理后,痊愈出院53例,好转3例,自动出院1例,院前死亡2例（眼镜王蛇咬伤1例,银环蛇咬伤1例）。结论院前急救是蛇伤治疗前期的一个关键性步骤,院前早期程序化急救处理方案应用于蛇伤患者,有利于提高抢救成功率。     

Integrating human behavior and snake ecology with agent-based models to predict snakebite in high risk landscapes

Snakebite causes more than 1.8 million envenoming cases annually and is a major cause of death in the tropics especially for poor farmers. While both social and ecological factors influence the chance encounter between snakes and people, the spatio-temporal processes underlying snakebites remain poorly explored. Previous research has focused on statistical correlates between snakebites and ecological, sociological, or environmental factors, but the human and snake behavioral patterns that drive the spatio-temporal process have not yet been integrated into a single model. Here we use a bottom-up simulation approach using agent-based modelling (ABM) parameterized with datasets from Sri Lanka, a snakebite hotspot, to characterise the mechanisms of snakebite and identify risk factors. Spatio-temporal dynamics of snakebite risks are examined through the model incorporating six snake species and three farmer types (rice, tea, and rubber). We find that snakebites are mainly climatically driven, but the risks also depend on farmer types due to working schedules as well as species present in landscapes. Snake species are differentiated by both distribution and by habitat preference, and farmers are differentiated by working patterns that are climatically driven, and the combination of these factors leads to unique encounter rates for different landcover types as well as locations. Validation using epidemiological studies demonstrated that our model can explain observed patterns, including temporal patterns of snakebite incidence, and relative contribution of bites by each snake species. Our predictions can be used to generate hypotheses and inform future studies and decision makers. Additionally, our model is transferable to other locations with high snakebite burden as well.     

Point-of-care infrared thermal imaging for differentiating venomous snakebites from non-venomous and dry bites

BackgroundLocal envenomation following snakebites is accompanied by thermal changes, which could be visualized using infrared imaging. We explored whether infrared thermal imaging could be used to differentiate venomous snakebites from non-venomous and dry bites.MethodsWe prospectively enrolled adult patients with a history of snakebite in the past 24 hours presenting to the emergency of a teaching hospital in southern India. A standardized clinical evaluation for symptoms and signs of envenomation including 20-minute whole-blood clotting test and prothrombin time was performed to assess envenomation status. Infrared thermal imaging was done at enrolment, 6 hours, and 24 hours later using a smartphone-based device under ambient conditions. Processed infrared thermal images were independently interpreted twice by a reference rater and once by three novice raters.FindingsWe studied 89 patients; 60 (67%) of them were male. Median (IQR) time from bite to enrolment was 11 (6.5–15) hours; 21 (24%) patients were enrolled within 6 hours of snakebite. In all, 48 patients had local envenomation with/without systemic envenomation, and 35 patients were classified as non-venomous/dry bites. Envenomation status was unclear in six patients. At enrolment, area of increased temperature around the bite site (Hot spot) was evident on infrared thermal imaging in 45 of the 48 patients with envenomation, while hot spot was evident in only 6 of the 35 patients without envenomation. Presence of hot spot on baseline infrared thermal images had a sensitivity of 93.7% (95% CI 82.8% to 98.7%) and a specificity of 82.9% (66.3% to 93.4%) to differentiate envenomed patients from those without envenomation. Interrater agreement for identifying hot spots was more than substantial (Kappa statistic >0.85), and intrarater agreement was almost perfect (Kappa = 0.93). Paradoxical thermal changes were observed in 14 patients.ConclusionsPoint-of-care infrared thermal imaging could be useful in the early identification of non-venomous and dry snakebites.