Incidence and treatment of snakebites in West Bengal, India

Kraits of Indian subcontinent: Natural history, risks, venom variation, lethality and treatment strategies - A comprehensive review

The World Health Organization (WHO) has re-classified "Snakebite" as a Neglected Tropical Disease in 2017, and estimated that as many as 5.4 million people suffer from snakebites every year. Out of this large number of snakebites, envenoming occurs in about 50 % of the cases, and the number of resulting deaths could be as high as 138,000. The genus Bungarus commonly known as kraits are medically important elapid snakes widely distributed in the Indian subcontinent, southern China and the Southeast Asian countries (except Philippines). The Indian subcontinent (India, Bangladesh, Bhutan, Nepal, Pakistan, Sri Lanka and Maldives) is home to 8-9 krait species, among which B. caeruleus and B. niger are highly venomous. This review presents the current state of knowledge on krait bites in the Indian subcontinent. The risk of envenomation by kraits, the venom lethality and krait bite management in the Indian subcontinent have been critically analyzed. Moreover, the issue of dry bites from kraits and their management has also been reviewed. Furthermore, critical aspects, such as knowledge of snakebite management among healthcare workers, clinical symptoms of snakebite patients, and treatment in healthcare facilities including antivenom administration and their clinical efficacy, have helped us in identifying the critical knowledge gaps. Proposed preventive measures will help to reduce krait bite associated mortality and morbidity. Moreover, development and accessibility to affordable treatment options may help in the effective management of krait bites.

Neurotoxic snakebite envenomation treated with Philippine cobra antivenom in the eastern Visayas: a descriptive study between 2016 and 2020

Introduction

There is a significant shortage of observational studies on neurotoxic snakebite envenomation in the Philippines. This lack of data, especially concerning treatment using Purified Cobra Antivenom (PCAV), has prompted the initiation of this foundational study.

Methods

The target population included snakebite patients admitted to the Eastern Visayas Medical Center and treated with PCAV between 2016 and 2020. A retrospective chart review was conducted for data collection. The investigation analyzed the hospital stay and patient features of individuals who were administered either lower or higher doses of PCAV.

Results

Eighty-two patients were identified during the study. Of these, 27 (33%) were under 20 years of age and 50 (61%) were male. Most patients, totalling 75 (92%) were hailed from rural areas. Of the 82 patients, 59 (72%) received one or two ampoules of PCAV during the course. However, patients who received more than two ampoules had a longer median hospital stay than those who received less than three ampoules [96 h (interquartile range, IQR 66-122) vs. 125 h (IQR 96-218), P = 0.038]. The study reported five in-hospital mortalities (6.1%).

Conclusions

The individuals who needed a high dosage of PCAV tended to have more extended hospital stays, yet over 70% of the patient population required a lower dosage. To gain a clearer understanding of the burden of neurotoxic snakebites and determine the optimal PCAV dosage based on disease severity in the area, a more comprehensive, prospective study is recommended.

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

Background

Snakebite 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 findings

The 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.

Conclusions

Death 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.

Snakebite is a global burden especially inflicting despair and torment among agronomist rural population of the society. This study has been conducted in small state of Sikkim in India which has not been actually considered so far in any of the national statistical condensation of snakebite cases. There are around 19 venomous snakes found in Sikkim of which five common ones co-exist with humans. Such co-existence may lead to unintentional encounter posing life threatening snakebite. People of Sikkim have strong belief on traditional healers for treatment of snakebite which results in mortality and morbidity. The present epidemiological study provides the baseline information compiling both hospital and community data and predict the areas having higher risk of snakebite envenomation in Sikkim. This study will help the authorities for better preparedness to deal with snakebite emergency to achieve minimum or no mortality. Potential risk mapping will help the health department for stocking anti-venom in nearby health centers. Most importantly, this study will create awareness among the people and the authority about snakebite which is considered as neglected tropical disease.

The role of pyridostigmine in recovery from motor paralysis in a snakebite patient with an allergic reaction to anti-snake venom

A 30-year-old woman presented as an emergency with a history of snakebite 5 h previously with signs of bulbar palsy, ptosis, respiratory distress and weakness of all four limbs. Mechanical ventilation, anti-snake venom (ASV) and supportive management were immediately instituted. With the third dose of ASV, an early anaphylactic reaction ensued. Subsequent management with corticosteroids and antihistamines over the next few days allowed consciousness to return but muscle power did not improve beyond 2/5. A trial of intravenous neostigmine with glycopyrrolate, however, improved motor power in all four limbs to 3/5. Oral pyridostigmine at 60 mg every 8 h allowed subsequent full motor recovery in all four extremities. We suggest consideration of pyridostigmine to promote motor recovery after an allergic reaction to ASV.

Clinico-epidemiology and management of Russell's viper (Daboia russelii) envenoming in dogs in Sri Lanka

INTRODUCTION

Russell's viper envenoming in dogs is a significant problem in Sri Lanka. The current study focused on investigating clinical profile, laboratory findings of three selected tests and to develop a treatment strategy with Indian polyvalent Anti-Venom Serum (AVS). It was also intended to report adverse effects and complications caused by both Russell's viper venom (RVV) and AVS in Russell's Viper (RV) envenomed dogs.

OBJECTIVE

To evaluate and report the clinical manifestations, to find out the minimum effective vials of AVS and to record AVS induced adverse reactions of RV envenoming in dogs.

MATERIALS AND METHODS

A prospective study was conducted on Russell's viper bitten dogs (n = 65) admitted to the Veterinary Teaching Hospital (VTH) in Sri Lanka. Indian polyvalent AVS was used to treat all the envenomed dogs. The number of vials of AVS that was administered to a patient was decided upon by a second degree polynomial model with a number of vials of AVS in the X axis verses Prothrombine Time (PT), Activated Partial Thromboplastine Time (aPTT) and Clotting Time (CT) in the Y axis respectively.

RESULTS

Varying degrees of pain were exhibited by all the victim dogs. Mild swelling and necrosis at the site of bite was seen in 54% (n = 35) and 37% (n = 24) of dogs respectively. Prolonged values of, PT, aPTT and CT were seen from all the RV envenomed dogs. The mean leukocyte count in these dogs was 39.79 × 103/μL (normal range; 4-20 × 103/μL) (IQR:29.05 × 103/μL-45.92 × 103/μL). Statistical analysis showed that the initial vials of 7 AVS would be the minimum required vials. Therefore, a range of 6-15 AVS vials in total were administered to these dogs and in 7.6% (n = 5) of dogs, the results of PT, aPTT and CT became normal with 6 AVS vials at 32-97 minutes. Acute Renal Failure (ARF) was detected from 29% (n = 19) of dogs as a complication.

CONCLUSIONS

Systemic clinical signs of haemorrhagic lesions, cardio respiratory toxicities were common in Russell's viper envenomed dogs. Initially 6 vials of AVS must be administered. AVS induced reactions were reported commonly. Russell's viper envenoming was found to be lethal in dogs.