BITES study: A qualitative analysis among emergency medicine physicians on snake envenomation management practices.

INTRODUCTION: Antivenom is currently considered standard treatment across the full spectrum of severity for snake envenomation in the United States. Although safe and effective antivenoms exist, their use in clinical practice is not universal. OBJECTIVE: This study explored physicians' perceptions of antivenom use and experience with snake envenomation treatment in order to identify factors that influence treatment decisions and willingness to administer. METHODS: We conducted a qualitative study including in-depth interviews via online video conferencing with physicians practicing in emergency departments across the United States. Participants were selected based on purposive sampling methods. Data analysis followed inductive strategies, conducted by two researchers. The codebook and findings were discussed within the research team. FINDINGS: Sixteen in-depth interviews with physicians from nine states across the US were conducted. The participants' specialties include emergency medicine (EM), pediatric EM, and toxicology. The experience of treating snakebites ranged from only didactic education to having treated over 100 cases. Emergent themes for this manuscript from the interview data included perceptions of antivenom, willingness to administer antivenom and influencing factors to antivenom usage. Overall, cost-related concerns were a major barrier to antivenom administration, especially in cases where the indications and effectiveness did not clearly outweigh the potential financial burden on the patient in non-life- or limb-threatening cases. The potential to decrease recovery time and long-term functional impairments was not commonly reported by participants as an indication for antivenom. In addition, level of exposure and perceived competence, based on prior education and clinical experience, further impacted the decision to treat. Resources such as Poison Center Call lines were well received and commonly used to guide the treatment plan. The need for better clinical guidelines and updated treatment algorithms with clinical and measurable indicators was stated to help the decision-making process, especially among those with low exposure to snake envenomation patients. CONCLUSIONS: A major barrier to physician use of antivenom is a concern about cost, cost transparency and cost-benefit for the patients. Those concerns, in addition to the varying degrees of awareness of potential long-term benefits, further influence inconsistent clinical treatment practices.

Utilization of thromboelastograms in management of Crotalus adamanteus envenomation.

BACKGROUND: Crotalinae (pit viper) envenomations are frequently encountered in North American emergency departments. Cases can be complicated by ambiguity in initial species identification as well as timing and duration of current antivenin treatment. Recently, thromboelastography (TEG) has emerged as an enhanced real-time monitoring parameter for snake envenomations that may aid in management of venom-induced consumptive coagulopathy. CASE: A 61-year-old snake handler presented with severe coagulopathy and hypofibrinogenemia following envenomation from her pet eastern diamondback rattlesnake (Crotalus adamanteus). Her coagulopathy transiently improved with Crotalidae Polyvalent Immune Fab (Ovine) (FabAV) but would repeatedly rebound following cessation of antivenin over the next 10 days. Serial TEGs were successfully utilized to identify and corroborate fibrinolysis while predicting clot formation prior to routine coagulation studies. DISCUSSION: Traditional coagulation parameters have not always been ideal when treating severe coagulopathy from pit viper envenomations and may not identify active fibrinolysis for several hours. In this case of C. adamanteus envenomation, TEG proved to be useful in demonstrating improvements in clotting function prior to standard laboratory measures, which further guided antivenin therapy.

Trends in snakebite deaths in India from 2000 to 2019 in a nationally representative mortality study.

The World Health Organization call to halve global snakebite deaths by 2030 will require substantial progress in India. We analyzed 2833 snakebite deaths from 611,483 verbal autopsies in the nationally representative Indian Million Death Study from 2001 to 2014, and conducted a systematic literature review from 2000 to 2019 covering 87,590 snakebites. We estimate that India had 1.2 million snakebite deaths (average 58,000/year) from 2000 to 2019. Nearly half occurred at ages 30-69 years and over a quarter in children < 15 years. Most occurred at home in the rural areas. About 70% occurred in eight higher burden states and half during the rainy season and at low altitude. The risk of an Indian dying from snakebite before age 70 is about 1 in 250, but notably higher in some areas. More crudely, we estimate 1.11-1.77 million bites in 2015, of which 70% showed symptoms of envenomation. Prevention and treatment strategies might substantially reduce snakebite mortality in India.

Clinical Features, Bacteriology, and Antibiotic Treatment Among Patients with Presumed Naja Bites in Vietnam.

INTRODUCTION: Clinical and bacteriological features of cobra (Naja) bites are still relatively unknown in Vietnam. This study aimed to characterize the clinical and bacteriological characteristics of local wounds in patients with presumed Naja spp bite, as well as their antibiotic treatment. METHODS: A cross-sectional study was performed on presumed Naja bite patients who were admitted to Bach Mai Hospital in Hanoi, Vietnam. In vitro bacterial isolation, blood tests, and lesion measure were conducted, and antibiotic susceptibilities of localized bite wounds were assessed. The Mann-Whitney test was used to examine the difference in clinical characteristics between patients experiencing presumed Naja atra bites and Naja kaouthia bites. Data are presented as percentages or median with interquartile range, as appropriate. Statistical significance was accepted at P<0.05. RESULTS: Among 46 patients, all had typical clinical features of Naja bite. The median bite-to-hospital time was 6 h (interquartile range 4.0-11.3). The dominant organisms isolated from local wounds were Morganella morganii (11/36) and Enterococcus faecalis (25/36). All cultures were susceptible to ciprofloxacin. No difference was found with regard to pain, swelling circumference, swelling spread, or necrotic area between patients bitten by presumed Naja atra and Naja kaouthia (P>0.05). CONCLUSIONS: Wound necrosis and infection were important clinical issues in presumed Naja spp snake bites. Morganella morganii and Enterococcus faecalis were dominant in local wound swabs of such cases. Ciprofloxacin should be an effective first-line antibiotic for patients with presumed Naja bite.

A case of envenomation by the false fer-de-lance snake Leptodeira annulata (Linnaeus, 1758) in the department of La Guajira, Colombia. / Un caso de envenenamiento por mordedura de una serpiente falsa cabeza de lanza, Leptodeira annulata (Linnaeus, 1758), en el departamento de La Guajira, Colombia

Envenomations by colubrid snakes in Colombia are poorly known, consequently, the clinical relevance of these species in snakebite accidents has been historically underestimated. Herein, we report the first case of envenomation by opisthoglyphous snakes in Colombia occurred under fieldwork conditions at the municipality of Distracción, in the department of La Guajira. A female biologist was bitten on the index finger knuckle of her right hand when she tried to handle a false fer-de-lance snake (Leptodeira annulata). Ten minutes after the snakebite, the patient started to have symptoms of mild local envenomation such as edema, itching, and pain in the wound. After 40 minutes, the edema reached its maximum extension covering the dorsal surface of the right hand and causing complete loss of mobility. The clinical treatment focused on pain and swelling control. No laboratory tests were performed. The patient showed good progress with the total regression of the edema 120 hours after the snake-bite accident and complete recovery of the movement of the limb in one week. Venomous bites of "non-venomous snakes" (opisthoglyphous colubrid snakes) must be considered as a significant public health problem because patients lose their work capability during hours or even days and they are forced to seek medical assistance to treat the envenomation manifestations.

Los envenenamientos por colúbridos en Colombia son poco conocidos, por lo que la relevancia clínica de estas especies de serpientes en los accidentes ofídicos ha sido históricamente subestimada. Se presenta el primer caso de envenenamiento por una serpiente opistoglifa en Colombia, ocurrido bajo condiciones de trabajo de campo en el municipio de Distracción, departamento de La Guajira. Una bióloga fue mordida en el nudillo del dedo índice de la mano derecha cuando trató de manipular una falsa cabeza de lanza o falsa mapanare (Leptodeira annulata). Diez minutos después de la mordedura de la serpiente, la paciente presentó síntomas de envenenamiento local leve, como edema, picazón y dolor en la herida. Después de 40 minutos, el edema alcanzó su extensión máxima, cubriendo la superficie dorsal de la mano derecha y causando la pérdida completa de la movilidad. El tratamiento clínico se centró en el control del dolor y la inflamación. No se hicieron pruebas de laboratorio. La paciente tuvo una buena evolución, con la regresión total del edema 120 horas después del accidente ofídico y la normalización de los movimientos de la extremidad a la semana. Las mordeduras venenosas de serpientes "no venenosas" (serpientes colúbridas opistoglifas) deben considerarse un problema de salud pública importante, ya que los pacientes pierden la capacidad de trabajo durante horas o días y se ven obligados a buscar asistencia médica para contrarrestar las manifestaciones locales de envenenamiento.

Consecutive envenomation of two men bitten by the same coral snake (Micrurus corallinus).

Objective: To report two patients who developed systemic neurotoxicity after consecutive bites by the same coral snake.Case report: Two previously healthy men (32-year-old and 34-year-old) found a coral snake in a woodpile while collecting wood for a barbecue. During the barbecue, both men became drunk and "played" with the snake, believing that they were handling a false coral snake, and were bitten within a few minutes of each other. Both patients were admitted to a referral tertiary care hospital (175 km from where the bites occurred) 16 hours and 19 hours postbite; both showed similar features of envenomation: palpebral ptosis, muscle weakness, dysphagia, and generalized myalgia. No fang marks or local pain were detected in either case. The patients were successfully treated with Brazilian coral snake antivenom (Fab´2) and discharged one-day postadmission, with improvement of myasthenia, but still showing palpebral ptosis. The offending snake was identified as a 42-cm-long Micrurus corallinus. During follow-up, both patients reported a transitory loss of taste that lasted approximately 3-4 weeks postbite.Conclusion: Consecutive bites by the same coral snake may cause systemic neurotoxicity (acute myasthenia) in more than one person, as well as transitory loss of taste, an underreported complication of snakebites.

Comparative study of the in vivo toxicity and pathophysiology of envenomation by three medically important Egyptian snake venoms.

Snakebite envenomation is a serious medical problem in many developing tropical and subtropical countries. Envenomation is registered by the World Health Organization as a neglected tropical disease due to critical shortages in the production of antivenom. Envenomation causes more than 100,000 deaths annually. Snakebites result in several effects to include edema, blistering, hemorrhage, necrosis and respiratory paralysis. Antivenom is the preferred treatment for the systemic effects of snakebite envenomation, though these are often ineffective in neutralizing venom toxin-induced local tissue damage. To effectively treat snakebites, it is important to determine the lethal potency and pathophysiological effects induced by specific snake venoms. In the current study, we compared the lethality, and the hemorrhagic and dermonecrotic activities of venoms from three snakes in Egypt that are the primary causes of local tissue necrosis. Our data show that the intraperitoneal median lethal doses (LD50) for Cerastes cerastes, Echis carinatus and Naja nigricollis venoms are 0.946, 1.744 and 0.341 mg/kg mouse body weight, respectively. These results indicated that N. nigricollis venom is the most toxic and significantly accelerated the time of death compared to the other two venoms. However, no hematoma or associated edema appeared upon sub-plantar injection of N. nigricollis venom into the mice hind paw. Two hours following intradermal injection of C. cerastes and E. carinatus venoms, macroscopic analysis of the inner surface of mouse skin showed severe hemorrhagic lesions, whereas only insignificant hemorrhagic lesion appeared in mice injected with the highest dose of N. nigricollis venom. Furthermore, the minimum necrotic doses (MND) for the same venoms were 43.15, and 70.87 µg/mouse, or not observed in the case of N. nigricollis venom, respectively. These LD50 values and pathophysiological results can be used to guide development of antivenom against bites by these dangerous Egyptian snakes.

Proteomic insights into short neurotoxin-driven, highly neurotoxic venom of Philippine cobra (Naja philippinensis) and toxicity correlation of cobra envenomation in Asia.

The Philippine cobra, Naja philippinensis, is a WHO Category 1 venomous snake of medical importance responsible for fatal envenomation in the northern Philippines. To elucidate the venom proteome and pathophysiology of envenomation, N. philippinensis venom proteins were decomplexed with reverse-phase high-performance liquid chromatography, and protein fractions were subsequently digested with trypsin, followed by nano-liquid chromatography-tandem mass spectrometry analysis and data mining. Three-finger toxins (3FTX, 66.64% of total venom proteins) and phospholipases A2 (PLA2, 22.88%) constitute the main bulk of venom proteome. Other proteins are present at low abundances (<4% each); these include metalloproteinase, serine protease, cobra venom factor, cysteine-rich secretory protein, vespryn, phosphodiesterase, 5' nucleotidase and nerve growth factor. In the three-finger toxin family, the alpha-neurotoxins comprise solely short neurotoxins (SNTX, 44.55%), supporting that SNTX is the principal toxin responsible for neuromuscular paralysis and lethality reported in clinical envenomation. Cytotoxins (CTX) are the second most abundant 3FTX proteins in the venom (21.31%). The presence of CTX correlates with the venom cytotoxic effect, which is more prominent in murine cells than in human cells. From the practical standpoint, SNTX-driven neuromuscular paralysis is significant in N. philippinensis envenomation. Antivenom production and treatment should be tailored accordingly to ensure effective neutralization of SNTX. BIOLOGICAL SIGNIFICANCE: The venom proteome of Naja philippinensis, the Philippine cobra, is unravelled for the first time. Approximately half the protein bulk of the venom is made up of short neurotoxins (44.55% of the total venom proteins). As the only alpha-neurotoxins present in the venom, short neurotoxins are the causative toxins of the post-synaptic blockade and fast-onset neuromuscular paralysis in N. philippinensis envenomation. A substantial amount of cytotoxins (21.31%) was also detected in N. philippinensis venom, supporting that the venom can be cytotoxic although the effect is much weaker in human cells compared to murine cells. The finding is consistent with the low incidence of local tissue necrosis in N. philippinensis envenomation, although this does not negate the need for monitoring and care of bite wound in the patients.

Snakebite accidents in Rio Grande do Norte state, Brazil: Epidemiology, health management and influence of the environmental scenario.

OBJECTIVES: Brazil is home to large variety of snake species, of which about 17% are venomous. A large proportion of reported snakebite accidents in the country take place in northeast Brazil. We aimed to analyse the epidemiology of snakebites as a public health concern in Rio Grande do Norte state. METHODS: A retrospective epidemiologic analysis was performed using data from the Brazilian Case Registry Database pertaining to the period 2007-2016, and considering environmental climate characteristics as an influential factor. RESULTS: A number of 3909 cases were reported in total. Among those cases, 58% involved venomous species and more than 80% of these were caused by Bothrops species. An association between environmental characteristics and the incidence of reported cases was found. The Borborema Potiguar region was the most affected area. Apart from that, deficiencies in managing the victims were described. CONCLUSION: This study highlights snakebite accidents as a public health concern in Rio Grande do Norte state. Snake bites are most likely being influenced by climate change and human activities. Continuous training of involved medical personnel could help optimise patient care and avoid under reporting in the accident reporting system.

OBJECTIFS: Le Brésil abrite de très nombreuses espèces de serpents, dont environ 17% sont venimeuses. Une grande partie des accidents rapportés de morsures de serpent dans le pays ont lieu dans le nord-est du pays. Notre objectif était d'analyser l'épidémiologie des morsures de serpents en tant que problème de santé publique dans l'Etat du Rio Grande do Norte. MÉTHODES: Une analyse épidémiologique rétrospective a été réalisée à l'aide des données de la Base de Données du Registre Brésilien des cas couvrant la période 2007-2016 et prenant en compte les caractéristiques climatiques de l'environnement comme facteur d'influence. RÉSULTATS: 3.909 cas au total ont été rapportés. 58% concernaient des espèces venimeuses et plus de 80% d'entre elles étaient causées par l'espèce Bothrops. Une association entre les caractéristiques environnementales et l'incidence des cas rapportés a été mise en évidence. La région de Borborema Potiguar était la plus touchée. Outre cela, les déficiences dans la prise en charges des victimes ont été décrites. CONCLUSION: Cette étude souligne que les accidents causés par des morsures de serpent constituent un problème de santé publique dans l'Etat de Rio Grande do Norte. Les morsures de serpents sont très probablement influencées par les changements climatiques et les activités humaines. La formation continue du personnel médical impliqué pourrait aider à optimiser les soins prodigués aux patients et à éviter une sous-notification dans le système de notification des accidents.

Berg adder (Bitis atropos) envenoming: an analysis of 14 cases.

INTRODUCTION: The berg adder (Bitis atropos) is a little-studied, lesser-known viperid snake found in southern Africa and there is limited information available regarding the manifestations of envenoming. MATERIALS AND METHODS: This observational series of 14 cases documents features of berg adder envenoming over a period of 16 years (1987-2003). Clinical features of envenomed patients: All 14 patients developed local cytotoxic effects. Thirteen patients developed systemic effects manifesting and documented in varying degrees. These include (1) prominent vomiting (2) disturbances in cranial nerve function (anosmia and altered taste, an ophthalmological triad of ptosis, mydriasis and visual disturbances including loss of accommodation, and dysphagia) (3) a global decrease in motor power where mechanical ventilation was often required for respiratory failure and (4) hyponatraemia (lowest value recorded 111 mmol/L), sometimes with associated convulsions. DISCUSSION: The full range of polypeptides present in berg adder venom is yet to be characterised. However, two closely related phospholipases A2 (PLA2; PLA2-1 and PLA2-2) have been purified from the venom of B. atropos and clinical evidence suggests that a natriuretic peptide is also possibly present. Envenoming results in distinctive, sometimes life-threatening, manifestations.

THE FIRST REPORT OF A CROTALID ENVENOMATION IN A DOMESTICATED FERRET ( MUSTELA FURO) AND SUCCESSFUL TREATMENT WITH A NOVEL F(AB')2 ANTIVENOM.

A case report of a domesticated ferret ( Mustela furo) envenomated by a presumptive rattlesnake ( Crotalus sp.) treated successfully and safely with the novel Fab (2') North American Snake Antivenom (Veteria Labs). The ferret presented with clinical signs of depressed mentation and facial edema following a rattlesnake ( Crotalus sp.) bite. It developed hypotension, thrombocytopenia, and ecchymosis following the envenomation. It was treated with Fab (2') antivenom and given supportive care including crystalloid fluids and analgesia to resolution of clinical signs. This is the first documented case of rattlesnake envenomation in this species. This case supports the efficacy and short-term safety of this Fab (2') antivenom in this species without the use of antihistamines or glucocorticoids. This report also addresses the current standards of care with thorough review of the literature involving rattlesnake envenomation in zoological species.

Snakebites Treated in North Carolina Emergency Departments, October 2013-September 2015.

INTRODUCTION: North Carolina (NC) is home to more than 30 species of indigenous venomous and nonvenomous snakes. Snakebites can cause debilitating and potentially fatal injuries. However, there is a lack of current information available describing the incidence of snakebites in NC. Therefore, we performed this study of snakebites treated in NC emergency departments (EDs) using the statewide syndromic surveillance system, the North Carolina Disease Event Tracking and Epidemiologic Collection Tool (NC DETECT). METHODS: This was a descriptive epidemiologic study characterizing NC ED visits collected by NC DETECT between October 1, 2013 and September 30, 2015 with an assigned International Classification of Diseases, 9th Revision, Clinical Modification code or keyword indicating a snakebite. RESULTS: Over the 2-year period, the absolute count of snakebite-related ED visits was 2080 visits with an incidence rate of 10.4 visits per 100 000 person-years (95% confidence interval: 10.0-10.9). The frequency of snakebite was highest during the summer months and evening hours. Men had higher incidence rates of snakebite-related ED visits than women, and residents of the Coastal Plain geographic region of NC had higher incidence rates than persons in other regions. CONCLUSIONS: The current study indicated that snakebites are common injuries treated at NC EDs, with a strong seasonal and geographic component. Additional research is needed to further characterize the circumstances associated with snakebites for the development of preventive measures and public health education.

The role of fresh frozen plasma in reducing the volume of anti-snake venom in snakebite envenomation.

Snakebite associated with a venom-induced consumption coagulopathy (VICC) is a major public health problem. Our study aims to evaluate if fresh frozen plasma (FFP), administered after anti-snake venom (ASV), restores coagulability rapidly. At admission, all snakebite victims with a whole blood clotting time (WBCT) >20 min received ten vials of ASV according to World Health Organization criteria. After 6 h, at the discretion of the physician, patients with WBCT >20 min were divided into two groups. The test group received both ASV and FFP and the control group received ASV only. The mean number of ASVs used in tests and controls were 17 and 31, respectively. The clotting time normalised at 24 h and 42 h in the test group and control group, respectively. FFP appears to aid restoration of clotting factors more rapidly and thus haemorrhage and the number of anti-snake venom vials used are both reduced.

Clinically Significant Envenomation From Postmortem Copperhead (Agkistrodon contortrix).

Over 14,000 copperhead (Agkistrodon contortrix) bites were reported to United States poison centers between 1983 and 2008, and 1809 cases were reported to poison centers in 2014. The copperhead is primarily found in the southeastern United States and belongs to the pit viper subfamily Crotalinae, which also includes the water moccasin (Agkistrodon piscivorus) and rattlesnakes (Crotalus and Sistrurus genera). Postmortem rattlesnakes have been reported to cause clinically significant envenomation; we report a case of a postmortem copperhead causing clinically significant envenomation after inadvertent puncture with the deceased copperhead fang. The copperhead was transected twice, leaving the snake in 3 separate pieces. While handling the snake head, an inadvertent puncture occurred on the right index finger followed by pain and swelling in the affected extremity necessitating antivenom administration. Care should be taken when handling deceased pit vipers due to the continued risk of envenomation.

Analgesic Effect of Photobiomodulation on Bothrops Moojeni Venom-Induced Hyperalgesia: A Mechanism Dependent on Neuronal Inhibition, Cytokines and Kinin Receptors Modulation.

BACKGROUND: Envenoming induced by Bothrops snakebites is characterized by drastic local tissue damage that involves an intense inflammatory reaction and local hyperalgesia which are not neutralized by conventional antivenom treatment. Herein, the effectiveness of photobiomodulation to reduce inflammatory hyperalgesia induced by Bothrops moojeni venom (Bmv), as well as the mechanisms involved was investigated. METHODOLOGY/PRINCIPAL FINDINGS: Bmv (1 µg) was injected through the intraplantar route in the right hind paw of mice. Mechanical hyperalgesia and allodynia were evaluated by von Frey filaments at different time points after venom injection. Low level laser therapy (LLLT) was applied at the site of Bmv injection at wavelength of red 685 nm with energy density of 2.2 J/cm2 at 30 min and 3 h after venom inoculation. Neuronal activation in the dorsal horn spinal cord was determined by immunohistochemistry of Fos protein and the mRNA expression of IL-6, TNF-α, IL-10, B1 and B2 kinin receptors were evaluated by Real time-PCR 6 h after venom injection. Photobiomodulation reversed Bmv-induced mechanical hyperalgesia and allodynia and decreased Fos expression, induced by Bmv as well as the mRNA levels of IL-6, TNF-α and B1 and B2 kinin receptors. Finally, an increase on IL-10, was observed following LLLT. CONCLUSION/SIGNIFICANCE: These data demonstrate that LLLT interferes with mechanisms involved in nociception and hyperalgesia and modulates Bmv-induced nociceptive signal. The use of photobiomodulation in reducing local pain induced by Bothropic venoms should be considered as a novel therapeutic tool for the treatment of local symptoms induced after bothropic snakebites.

Agriculture and snakebite in Bahia, Brazil - An ecological study.

This study investigated the correlation between the incidence of snakebite and indicators of agricultural development in municipal districts of the State of Bahia, Brazil. An ecological study was conducted with the 27,347 cases of snakebite poisoning reported to the Reportable Diseases National Information System in municipalities from the State of Bahia, Brazil, 2000-2009. The unit of analysis was each one of the 417 State municipalities, and the outcome variable was the average annual incidence of snakebite. Data were analyzed by multiple linear regression technique. The average annual incidence of snakebite ranged from zero to 221.96 per 100,000 inhabitants, according to the municipalities. The incidence of snakebite was positively and strongly associated with municipality characteristics: planted areas of cocoa and coffee, and the size of domestic bred chicken and bovine livestocks. It was concluded that several characteristics related to municipal agricultural profile were strongly associated with the incidence of snakebite.

Snakebite by the Shore Pit Viper (Trimeresurus purpureomaculatus) Treated With Polyvalent Antivenom.

Although snakebites are uncommon, there are several species of medically important venomous snakes native to Singapore. We present a case of envenoming by the shore pit viper (Trimeresurus purpureomaculatus) that showed clinical improvement when treated with the Indian (Haffkine) polyvalent antivenom. A 40-year-old man was bitten on his right hand by a snake, which was identified through photos and his description to be a shore pit viper, which is native to the local mangrove area. Severe swelling and pain developed immediately after the bite, which progressed up the arm. Because of the progression of local swelling, antivenom was started. He was given a total of 6 vials (60 mL) of polyvalent antivenom, with the first vial started 3 hours after the bite. He showed clinical improvement within 24 hours. His subsequent recovery was uneventful, with no other complications as a result of envenomation or antivenom use. Severe envenoming by the shore pit viper can lead to marked local effects such as extensive swelling and tissue necrosis. Antivenom is indicated in the presence of severe local envenomation. Antivenom against the shore pit viper is however not available locally. The Indian (Haffkine) polyvalent antivenom contains antibodies against 4 common venomous snakes in India, namely the Indian cobra, common krait, Russell's viper, and sawscaled viper. The improvement seen in this patient suggests possible cross-neutralizing activity of the Indian vipers' antivenom against the local shore pit viper venom. Further in vivo and in vitro studies should be performed to verify this clinical case.

Estimating the Burden of Snakebite on Public Hospitals in KwaZulu Natal, South Africa.

OBJECTIVE: We propose a formula as a means to estimate the number and incidence of snakebites treated per annum in KwaZulu Natal (KZN), South Africa. METHODS: Using an unvalidated formula that includes an antivenom ratio, we crudely estimated the total number of snakebite presentations in KZN. Using antivenom supply data from the central pharmacy, we stratified a sample of 6 hospitals that were surveyed to establish an antivenom ratio, that is, the total number of patients receiving antivenom to the total number of snakebite presentations at hospitals. The antivenom ratio and the average number of antivenom vials for treated snakebites were incorporated into a formula to crudely estimate the number of snakebite presentations. This was then applied to all public hospitals and districts in the region. RESULTS: Seventy-eight percent of public hospitals were included. The mean antivenom ratio derived from the sample hospitals indicated that 12% (95% CI, 10-14%) of snakebite presentations received antivenom. We estimated an annual total of 1680 (95% CI, 1193-2357) snakebite presentations to hospitals. Two thirds of cases (1109 of 1680) were in the low-lying subtropical coastal region. Few cases were in the higher, cooler regions of KZN (87 of 1680) or the metropolitan city of Durban (93 of 1680). The overall incidence for KZN was 16/100,000. The estimated cost of snakebite in KZN was between $1,156,930 and $2,827,848. CONCLUSIONS: We propose an alternative method to estimate the annual number of snakebite presentations to hospitals.